Browse Topic: Waste heat recovery

Items (335)
Find
Potential of ORC-Based Waste Heat Recovery in Conventional and Hybrid Heavy-Duty Powertrains2026-37-00186/9/2026
Heavy-duty vehicles significantly contribute to greenhouse gas emissions and urban air pollution, especially during cold-starts and transients when engine and aftertreatment efficiencies drop. Waste heat recovery (WHR) via Organic Rankine Cycle (ORC) systems offers a practical solution to improve fuel efficiency and cut CO₂ in real-world heavy-duty operations. This study examines ORC-based WHR integration into conventional and hybrid powertrains of an Isuzu FTR850 truck, analyzing four configurations: Shell-and-Tube or Plate heat exchangers with simple or regenerative ORC layouts. For hybrids, it compares two engine sizes and energy management strategies: an optimized fuzzy logic approach versus constant-power operation to enhance exhaust heat recovery. A validated quasi-static simulation framework is used to predict fuel consumption and exhaust properties over representative duty cycles. 2D performance maps using exhaust temperature and mass flow as inputs are used to model the WHR under off-design conditions. Results show that the recovery of waste heat WHR depends on the hybridization level and strategy. Conventional powertrains benefit most from Shell-and-Tube exchangers, recovering ~2 kWh of electrical energy per 8-hour cycle and reducing fuel consumption by 0.5%. Hybrid setups recover up to 3.9 kWh from exhaust gases with a simple layout coupled with a Shell-and-Tube heat exchanger under constant-power control. Electricity is used to support onboard auxiliaries and battery charging, further lowering fuel demand (-44%) and emissions. Finally, a multi-objective optimization was performed to exploit the synergy between hybridization and WHR while maintaining acceptable payload and battery operating conditions.
Donateo, Teresa, Morrone, Pietropaolo
Multi-Physics Modeling of Aircraft Hybrid Propulsion Systems Integrating Batteries, SOFC, and Jet Engine2026-99-17035/22/2026
This paper presents a multi-physics modeling approach for a hybrid propulsion system designed for High-Altitude Long-Endurance Unmanned Aerial Vehicles (HALE UAVs), integrating solid oxide fuel cells (SOFCs), lithium-ion batteries, and a jet engine. A dynamic model was developed to analyze the coupled characteristics of pressure, temperature, and power under steady-state conditions. Simulation results demonstrate that the internally integrated system achieves efficient fuel and waste heat recovery, delivering a net power output of 300–700 kW, sufficient to meet the operational demands of HALE UAVs. Key innovations include a heat exchanger maintaining SOFC stack inlet temperatures above 850 K for optimal performance and a compressor-fan subsystem enhancing gas compression efficiency. Experimental validation confirmed the accuracy of the SOFC model, with simulated electrical characteristics aligning closely with empirical data. The proposed hybrid system addresses limitations in specific power and transient response while improving energy density, offering a viable solution for long-endurance flight missions. This study provides a foundational platform for advancing hybrid propulsion technologies in aviation.
Zhang, Lin, Zhang, Di, Zhao, Lulu, Li, Xi
Research on Waste Heat Recovery Characteristics of Electric Drive System in Hybrid Electric Light-Duty Trucks2026-99-07225/15/2026
Aimed at the high energy consumption for battery heating of a light hybrid truck in low-temperature winter, this paper proposes an optimized battery thermal management scheme based on motor waste heat and PTC cooperation. Then it verifies its energy-saving performance based on multi-condition simulation and testing. Taking the constant-speed condition at -5°C as an example, firstly, the accuracy of the battery thermal management model is verified by comparative simulation and test. Then, based on the verified model, the battery thermal management model is simulated under typical winter conditions at 0°C and 5°C. The analysis results show that, when the battery temperature is raised from the initial state to a certain target, the energy consumption of the motor waste heat-assisted PTC heating scheme is obviously less than that of PTC heating. The energy saving rates are 33.137% at -5°C, 32.45% at 0°C, and 32.56% at 5°C, respectively. The research results have proved that the effective utilization of motor waste heat can reduce PTC energy consumption.
Meng, Shun, Zhang, Dong, Zhang, Yu, Zhang, Chunyu, Yao, Mingyao, Qiu, Liang, Qian, Yejian
Novel Air System for 300 kW Heavy Duty Fuel Cell2026-01-04344/7/2026
Hydrogen fuel cell powered vehicles for heavy duty trucking are a promising path for reducing future vehicle emissions due to their reduced mass for storage and faster refueling compared to battery electric trucks. These benefits come at the cost of increased system complexity stemming from the fact that fuel cells generate electricity through a chemical reaction which must be tightly controlled. The air handling system delivers the proper amount of air (oxygen) to react with fuel (hydrogen) in the fuel cell to produce power. Air delivery requires significant power and is the largest parasitic loss for a 300 kW fuel cell. Today’s systems use an electric motor driving an air compressor to supply pressurized air to the fuel cell stack. By operating at elevated pressure levels, fuel cells can achieve higher power density, which is important for vehicle powertrains. In addition to parasitic power loss, hydrogen fuel cell systems often have reliability issues associated with the air handling system. Reliability is of significant concern for heavy duty applications (especially long-haul applications). This project aims to improve both the electrical power consumption and reliability of hydrogen fuel cell air handling systems to meet the needs of heavy duty on-highway vehicle applications. The air handling is provided by a twin vortices series (TVS) compressor in addition to adding a TVS expander to recover waste heat energy back into the compressor. The final configuration includes a 600 V, 39 kW motor connected with a single shaft to the compressor and expander. This configuration reduced the total electrical power consumption from 48.6 kW to 37 kW at full load, 13.1 kW to 9 kW at half load and 0.44 kW to 0.22 kW at idle. The response time requirement was to be less than 2 sec while the final demonstration yielded 0.62 sec. Additional design changes, including water dosing into the compressor, addition of a recuperator, and elimination of the intercooler, were made to increase the energy efficiency of the air system.
Reich, Evan, Swartzlander, Matthew, Wine, Jonathan, McCarthy, Jr., James, Miller, Eric, Akhtar, Saad, Reddy, Sharan, Lawy, TJ
Modular Smart Corner Systems for Next-Generation Electric Vehicle Architecture2026-01-06394/7/2026
The transition to software-defined vehicles (SDVs) necessitates a paradigm shift in both control strategies and vehicle architecture. The EU-funded R&D project SmartCorners addresses this challenge by developing integrated, modular, and scalable smart corner systems (SCS) that combine in-wheel motor (IWM)-based propulsion, brake blending, active suspension system, and steer-by-wire functionality in one module. These SCS can be retrofit or smoothly integrated into the highly adaptable skateboard chassis architecture of modern electric vehicles (EVs), enabling scalable deployment across diverse vehicle types. The central approach of this paper is the utilization of artificial intelligence (AI) and machine learning (ML) to implement multi-layer, data-driven control strategies, facilitating real-time actuation, fault mitigation, and user-centric EV architecture. The SmartCorners project strives to demonstrate significant enhancements, including improved real-world driving range due to enhanced energy-efficiency, reduced component and system costs, and a cut-down in development time of EVs, enabled by digital-twin-based design methodologies. Beyond these performance gains, SmartCorners establishes the foundational principles of modularity, adaptability, and software integration that underpin the evolution toward SDVs. The role of thermal and cabin comfort control is completely different for EVs and internal combustion engine vehicles, with the latter using waste heat from the combustion of fossil fuels for cabin heating, ventilation, and cooling (HVAC). In EVs the required energy is directly taken from the traction battery and precise thermal and cabin comfort control affecting essential components of the vehicle but also the user-perceived driving experience. These project achievements highlight a critical bridge between innovation and electrification on component-level, and the holistic software-defined mobility systems of the future.
Ratz, Florian, Armengaud, Eric, Formento, Cecilia, Moscone, Giulia, Sorrentino, Gennaro, Bisciaio, Giorgio, Sorniotti, Aldo, Amati, Nicola, Braun, Daniel, Deibler, Bernd, Boxberger, Valerius, Sottile, Salvatore, Ivanov, Valentin, Fuse, Hiroyuki, Kompara, Tomaž
Standardization of On-Vehicle Measurement of BEV Thermal System Energy Consumption and Range Impacts2026-01-01324/7/2026
This paper presents research and digital twin modeling results to support work on a methodology to properly account for the energy consumed by the thermal system of a BEV, for use within both existing Petroleum-Equivalent Fuel Economy (PEFE) calculations, and the proposed addition of hot and cold weather range values to the consumer-facing Monroney label [1]. Properly accounting for thermal system impacts would incentivize minimizing energy consumption of these systems, since 1) BEV PEFE is a direct input to an OEMs overall CAFE performance, and 2) the values on the Monroney label has some impact on consumer vehicle choice. The impetus for this work was Final Rules issued by the EPA and NHTSA in early 2024 eliminating A/C Efficiency Credits for BEVs from the 2027 MY, thus eliminating regulatory incentives to minimize energy consumption of these systems. Higher energy consumption will produce a number of negative secondary effects, including higher real-world greenhouse gas emissions, reduced vehicle range, greater strain on the nation’s electrical grid, and higher vehicle mass leading to reduced vehicle safety - should OEMs opt to merely install larger batteries to address cold and hot weather range impacts instead of implementing lower energy-consuming technology. The results from the analysis, which ideally would be confirmed with follow-up vehicle tests, show that for a baseline, PTC-heat based system, thermal system energy consumption represents 19.2% of the total energy consumed by a BEV on an annual basis, using an ambient-VMT weighted approach. It seems to be the technical equivalent of “straining at a gnat while swallowing a camel” to focus so much time and energy on identifying incremental improvements in energy consumption from the propulsion-portion of a BEV, while by comparison ignoring the system that according to this analysis can account for nearly 20% of the total on an annual basis.
Taylor, Dwayne
The Membrane Engine: Concept, Model, and First Results03-19-01-00032/12/2026
This study investigates the feasibility of a novel internal combustion engine (ICE) architecture, termed the membrane engine, in which the conventional piston is replaced by a flexible elastic membrane. Although the concept appears in several patent documents proposing reduced friction, improved sealing, and lower heat losses, no empirical data has been published to support these claims. To the authors’ knowledge, this work presents the first membrane engine built and experimentally tested. The primary aim is to verify whether such an engine can operate as a functional ICE, regardless of its current efficiency or performance level. To support concept validation, a simplified mathematical model was developed to describe the membrane’s deformation and its effect on combustion chamber volume. Unlike conventional piston engines, the membrane introduces a pressure-dependent geometry, enabling a variable compression ratio. The model is not intended to predict performance but to assist in interpreting experimental results and assessing feasibility. It combines geometric and pressure-induced volume changes and was constructed conservatively to avoid overestimating deformation effects. A single-cylinder spark-ignition prototype was built by modifying an existing piston engine. Experimental tests were conducted under motored and fired conditions, with comparative measurements taken against the unmodified engine. Results confirmed that the membrane engine can sustain combustion and produce torque. Notably, the exhaust stroke exhibited a steeper pressure drop, suggesting improved scavenging, and the torque trace showed a distinct positive spike post-combustion. These findings support the hypothesis that the membrane’s dynamic behavior influences combustion and gas exchange. While some patent claims remain unverified, the study demonstrates that the membrane engine is a viable concept. The results provide a foundation for further development and refinement, including material selection and advanced modeling. Future work will focus on improving durability, expanding the operating envelope, and exploring hybrid configurations for waste heat recovery.
Allmägi, Roland, Ilves, Risto
TwinAV: Valve Timing Strategy for Divided Exhaust Periods in Turbocharged Spark-Ignition Engines: A Simulation-Based Evaluation03-19-01-00022/6/2026
Turbocharging is a common and simple method to utilize the exhaust heat of an internal combustion engine. However, conventional turbocharging exhibits the drawback of exhaust gas backpressure and thus increased residual gas mass in the cylinder. A promising concept to increase optimum efficiency is found in the TwinAV concept, which assigns divided exhaust valve cam timing and exhaust manifold configuration. This concept is hypothesized to reduce the static backpressure in the gas exchange loop and the residual exhaust gas amount in the gas exchange phase. In this article, a 1D simulation model was adapted to an existing 4-cylinder gasoline TC engine. Subsequently, the engine concept was applied to this engine model, whereas the focus was to achieve an engine layout for the entire engine speed range applicable for use in passenger vehicles. The results were compared at the full RPM range. Also, a load variation was conducted and benchmarked. The found results show an additional specific fuel consumption benefit of 6.4%, which is partly achieved by the reduced static backpressure and partly a result of less knock sensitivity due to less remaining internal EGR, observed in an earlier CA50 and peak pressure position. Simulation results indicate benefits in the upper half of the engine map and a maximum benefit in a region around the engines’ sweet point. This is a conceptual simulation-based study; no experimental or transient validation has been conducted.
Gotter, Andreas, Gotter, Alexander
Thermal Management Control Strategy for Primary & Secondary Drive Cooling Hybrid Electric Tractor2026-26-00691/16/2026
Global emission norms are getting very strict due to combat the harmful pollutants from internal combustion engine. Hence internal combustion engine (ICE)-based agricultural tractors need to introduce complex after-treatment systems and fuel optimization to provide same or higher value to farmers as cost of these systems drive the overall cost of the product. Engineers around the world are building Electric vehicles to combat the problem and has range issues due to design constraints & Hybrid tractors have emerged as a promising intermittent solution. It helps in combining the advantages of respective ICE and electrification solutions while reducing overall vehicle emissions and enhances operational flexibility. This paper presents a modular thermal modes system developed for a hybrid electric tractor platform where a downsized diesel engine operates at optimal efficiency DC generator used to charge the battery & DC converter is used to charge the auxiliary battery. Battery which is used to turn powers three independent motors. Primary & Secondary drive cooling. To maintain optimal operating temperatures of engine, power electronics components (battery, inverter, and motors), a smart thermal control architecture is developed using a radiator-based liquid cooling system. Engine waste heating recovery used for battery pre-conditioning. The system is designed with the capability to cool, engine, battery & power electronics. This thermal management control strategy cooling system works based on coolant temperature, battery temperature & ambient condition, control valves and temperature sensor send request to the VCU. VCU monitor the temperature, voltage & current. It communicates with battery BMS & motor controller within the tractor. This paper outlines the system objectives, architecture, operational thermal modes, and the control logic that enables modular thermal response. Proper thermal logic to be developed for various operating states and operating environments. In the present study thermal management control strategy has been derived and explained in the technical paper
K, Sunil, D, Mari, Natarajan, Saravanan, Kumawat, Deepak, rojamanikandan, Arumugham, K, Mala, V, Sridharan, Muniappan, Balakrishnan, Makana, Mohan
Waste Heat Recovery Evaluation in FCEV Truck on Different Drive-Cycles2026-26-02591/16/2026
Growing global warming and the associated climate change have expedited the need for adoption of carbon-neutral technologies. The transportation sector accounts for ~ 25 % of total carbon emissions. Hydrogen (H2) is widely explored as an alternative for decarbonizing the transport sector. The application of H2 through PEM Fuel Cells is one of the available technologies for the trucking industry, due to their relatively higher efficiency (~50%) and power density. However, at present the cost of an FCEV truck is considerably higher than its diesel equivalent. Hence, new technologies either enabling cost reduction or efficiency improvement for FCEVs are imperative for their widespread adoption. FCEVs have a system efficiency around 40-60% implying that around half of the input energy is lost to the environment as waste heat. However, recapturing this significant amount of waste heat into useful work is a challenge. This paper discusses the feasibility of waste heat recovery (WHR) technology for a long-haul FCEV heavy duty truck with a rated power of 300 kW. Two WHR system are evaluated – widely used Organic Rankine Cycle (ORC). Working fluids considered for the ORC model are R1233zd(E), R245fa and n-Pentane. The 0-D model of the ORC based WHR systems is developed in Matlab-Simulink platform for analysis. The waste heat generated is quantified at different drive-cycles, namely flat, moderate hilly and hilly terrain, using a complete vehicle simulation tool developed in Simulink platform. The waste heat data from complete vehicle simulation tool is provided as an input for the developed 0-D WHR models. The results show a considerable improvement in the overall fuel consumption of FCEV trucks with WHR systems. The findings imply the importance of WHR in FCEV truck to improve the overall system efficiency.
P V, Navaneeth
Design and Analysis on Integrated Thermal Management Solution for Electric Vehicles2025-28-041810/30/2025
Thermal Management System (TMS) for Battery Electric Vehicles (BEV) incorporates maintaining optimum temperature for cabin, battery and e-powertrain subsystems under different charging and discharging conditions at various ambient temperatures. Current methods of thermal management are inefficient, complex and lead to wastage of energy and battery capacity loss due to inability of energy transfer between subsystems. In this paper, the energy consumption of an electric vehicle's thermal management system is reduced by a novel approach for integration of various subsystems. Integrated Thermal Management System (ITMS) integrates air conditioning system, battery thermal management and e-powertrain system. Characteristics of existing integration strategies are studied, compared, and classified based on their energy efficiency for different operating conditions. A new integrated system is proposed with a heat pump system for cabin and waste heat recovery from e-powertrain. Various cooling and heating strategies for battery are identified for different ambient temperatures. An ITMS valve functioning is explained for each scenario depending on vehicle operating condition and ambient temperature.
K, Muthukrishnan, S, Saikrishna, Mahobia, Tanmay, Vijayaraj, Jayanth Murali
Thermal Management in Electrified Transportation: A Comparative Study of Different Powertrain Technologies2025-28-041210/30/2025
The transition towards sustainable transportation necessitates the development of advanced thermal management systems (TMS) for electric vehicles (EVs), hybrid electric vehicles (HEVs), hydrogen fuel cell vehicles (FCVs), and hydrogen internal combustion engine vehicles (HICEVs). Effective thermal control is crucial for passenger comfort and the performance, longevity, and safety of critical vehicle components. This paper presents a rigorous and comparative analysis of TMS strategies across these diverse powertrain technologies. It systematically examines the unique thermal challenges associated with each subsystem, including cabin HVAC, battery packs, fuel cell stacks, traction motors, and power electronics. For cabin HVAC, the paper explores methods for minimizing energy consumption while maintaining thermal comfort, considering factors such as ambient temperature, humidity, and occupant load. The critical importance of battery thermal management is emphasized, with a focus on preventing thermal runaway and maximizing battery lifespan through precise temperature regulation. The complexities of fuel cell stack thermal management are addressed, considering the electrochemical reactions and the need for uniform temperature distribution for optimal performance and durability. Furthermore, the paper investigates the thermal behavior of high-power traction motors and power electronics, analyzing different cooling techniques and their impact on efficiency and reliability. A comparative assessment of various cooling technologies, including forced air convection, liquid cooling, and emerging two-phase cooling methods, is provided. The paper also delves into integrating these individual TMS components, exploring opportunities for waste heat recovery and holistic system optimization. Finally, the paper identifies critical research gaps and outlines future directions in the development of intelligent and adaptive thermal management systems for next-generation electrified vehicles, emphasizing the need for robust control algorithms, advanced materials, and innovative cooling architectures.
K, Neelima, K, Anisha, Ch, Kavya, C, Somasundar, Satyam, Satyam, P, Geetha
A Critical Assessment of Alternative Refrigerants and Waste Heat Recovery for Sustainable Thermal Systems2025-28-035610/30/2025
The increasing demand for heating and cooling, coupled with growing environmental concerns, necessitates a paradigm shift towards sustainable thermal management practices. This paper presents a rigorous and scholarly investigation into innovative heating and cooling concepts, with a specific focus on the development and implementation of alternative refrigerants and waste heat recovery systems. The transition away from conventional refrigerants, with their detrimental impact on the environment, is explored through a comprehensive analysis of promising alternatives. Hydrofluoroolefins (HFOs), natural refrigerants (e.g., CO2, hydrocarbons, ammonia), and their blends are critically evaluated, considering their thermodynamic properties, environmental impact (GWP, ODP), safety considerations (flammability, toxicity), and application-specific performance. The paper delves into the intricacies of advanced cooling technologies, including absorption cooling, adsorption cooling, and thermoelectric cooling, examining their potential for enhanced energy efficiency and their ability to utilize low-grade heat sources. A significant contribution of this work lies in its in-depth exploration of waste heat recovery systems. Various techniques for capturing and effectively utilizing waste heat, such as heat exchangers, heat pumps, and organic Rankine cycles (ORCs), are comprehensively discussed and compared, with a focus on maximizing energy recovery and minimizing exergy destruction. The synergistic integration of these waste heat recovery systems with both conventional and alternative cooling technologies is examined, highlighting the potential for substantial energy savings and a reduced reliance on fossil fuels. The challenges associated with the adoption of these innovative technologies, including cost-effectiveness, material compatibility, system complexity, and safety implications, are critically assessed. Finally, the paper identifies key research gaps and outlines future directions in the pursuit of sustainable and efficient thermal management solutions, emphasizing the need for further research into novel refrigerants, advanced materials, optimized system design, and robust control strategies.
K, Neelima, Ch, Kavya, C, Somasundar, B, Harichandana, Satyam, Satyam, P, Geetha
Thermodynamic Exergy Analysis of PEMFC Systems for System Efficiency and Waste Heat Recovery2025-28-035210/30/2025
Proton Exchange Membrane Fuel Cell (PEMFC) vehicles are emerging as a promising green alternative to fossil fuel and battery-operated electric vehicles. Fuel cells convert the chemical energy of fuel to direct current (DC) through electrochemical reactions, rejecting some heat in the process. This study aims to minimize heat generated during these reactions within the fuel cell stack and utilize it to enhance stack efficiency. Through thermodynamic modeling and exergy analysis, the research focuses on reducing waste heat from exothermic reactions in PEMFC stacks. It investigates using low-temperature waste heat for heating hydrogen and inlet air also examining into how stoichiometry and current density influence heat reduction. Analytical studies were carried out using air stoichiometry ranging from 1.5 to 2 and ambient temperatures typical of Bangalore's climate (15°C to 35°C). The results show that increasing the current density from 1 A/cm2 to 1.5 A/cm2 significantly raises the hydrogen power requirement and stack power output, however, it leads to a decrease in overall system efficiency, from 57% to 49%, due to higher exergy losses. In addition, as ambient temperature rises from 288.15 K to 308.15 K, reduces the overall efficiency of the system, primarily due to higher auxiliary power consumption. Cathode stoichiometry also plays a crucial role, increasing stoichiometry from 1.5 to 2 resulting in higher compressor power consumption and more waste heat generation. Furthermore, Auxiliary parts like heat exchangers and air compressors require a significant amount of power in which emphasizes the need for system optimization. Heating inlet gases with hot cooling water can boost system efficiency by 1% and save around 2.7 kW of energy. System efficiency could be substantially enhanced by effectively utilizing the stack's waste heat.
Sahu, Tomesh Kumar, Bansode, Annasaheb
Analysis and Simulation of Fuel Consumption and Emissions in a Heavy-Duty Diesel Truck under Real-World Driving Conditions for Hybridization and Waste Heat Recovery2025-24-00969/7/2025
Heavy-duty vehicles contribute significantly to global greenhouse gas emissions and are now facing challenges in meeting emission regulatory standards, particularly cold-start operations. These challenges are particularly significant during transient operations, where fuel efficiency drops and emissions peak due to suboptimal thermal conditions. Advanced powertrains that use hybridization and waste heat recovery with phase-changing materials offer potential pathways to mitigate fuel consumption and emissions under real-world driving conditions. Still, they need to be accurately sized, and the energy flows handled to overcome the disadvantages of increased mass and complexity. This investigation lays the groundwork for the development of advanced power systems by implementing a scalable, map-based model for heavy-duty diesel engines. The model is validated using an open-access dataset related to a heavy-duty vehicle equipped with a 6-cylinder diesel engine, which performed 28 different trips on the same route with the same driver. The trips are executed with three different payload values and contain both cold-start and hot-start operating conditions. The validation is based on quasi-static modeling of the vehicle powertrain. The proposed model can accurately predict fuel consumption and CO2 emissions for all trips, with an average relative error of 2.4%. The results of the investigation also include preliminary sizing and analysis of a hybrid electric configuration that exploits the synergy between hybridization and waste heat recovery. In comparison to the original powertrain, the proposed powertrain resulted in a roughly 15% reduction in fuel consumption and a 37.5% increase in exhaust temperature. These findings demonstrate the potential for integrated hybrid and waste heat recovery systems to enhance fuel economy in heavy-duty transportation while supporting compliance with emission regulations.
Donateo, Teresa, Mujahid, Talha, Morrone, Pietropaolo, Algieri, Angelo
Waste Heat Recovery in Hydrogen Fueled Internal Combustion Engines2025-24-01089/7/2025
Waste Heat Recovery is one of the most investigated and promising technologies for energy efficiency in the transportation sector. It consents to maintain the high-level technology of the present propulsion systems, based on Internal Combustion Engines, while increasing the overall engine and vehicle system efficiency. At the same time, the use of alternative fuels, like hydrogen, has the same crucial role to reduce harmful and greenhouse emissions, without overturn the existing mature technology. A hydrogen-fueled Internal Combustion Engine is proposed in this paper, equipped with waste heat recovery consisting in an additional radial turbine downstream the turbocharger of the engine (Turbo-Compound). The aim is to have a reduction of the specific consumption in most of the operating points of the engine, considering the effect of the recovery and the engine equilibrium rearrangement. The use of hydrogen increases recoverable enthalpy at the engine exhaust, which is intended to be recovered through an expansion of the gases inside the additional turbine. When this secondary turbine is installed downstream of the turbocharger, the overall engine backpressure increases. This alters the turbocharger's operating point, which in turn shifts the engine’s operating conditions. Ultimately, this has a counterproductive effect on the engine efficiency: it faces higher backpressure at exhaust valve opening, leading to an increase in specific fuel consumption. This paper examines the modifications to the engine’s exhaust line resulting from the conversion of waste heat into mechanical energy via a Turbo-Compound system. It discusses the conditions under which the system yields a net positive effect, primarily by compensating for the increased back pressure it introduces. Changes in key engine parameters—such as Variable Geometry Turbocharger control, boost pressure, air/fuel mass flow rate, and equivalence ratio—are analyzed, along with their influence on in-cylinder pressure. Furthermore, the paper identifies the operating range in which the Turbo-Compound system provides a net performance benefit.
Di Battista, Davide, Cipollone, Roberto, Corti, Enrico, Brancaleoni, Pier Paolo, Di Prospero, Federico, Ravaglioli, Vittorio
Zero-Carbon Port Fueling for Heavy Propulsion through a Recuperated Split Cycle Engine2025-24-00449/7/2025
Upcoming global emissions regulations demand innovation in heavy-duty road and marine transport. This research explores emissions-compliant concepts using both experiments and simulations focused on the Recuperated Split Cycle Engine (RSCE), which separates compression and expansion to enable internal heat recovery and quasi-isothermal compression. A single-cylinder research engine representing the expansion cylinder of an RSCE demonstrated direct injection diesel and port injection hydrogen co-firing. A validated Chemkin-Pro Multi-Zone model first reproduced, then extended this work, evaluating partial diesel substitution with hydrogen or ammonia alongside secondary working fluids (SWF’s liquid N₂, H₂O, NH₃). For the extension, two variants of the split cycle architecture were employed; the RSCE in combination with hydrogen fueling for the heavy-duty road sector, and the novel recuperated reformed split cycle engine (R2SCE), a new architectural and simulation contribution enabling on-board ammonia reforming and dual-role use of SWFs for the maritime sector. In the RSCE configuration, 10%Vol H₂ with H₂O as SWF delivered 13% NOx and 45% CO₂ reductions, along with a 33% improvement in brake specific fuel consumption (BSFC). System-level evaluation of this configuration demonstrated the potential of Euro 7 compliant NOx with typical after-treatments. In the R2SCE configuration, while SWFs N₂ and H₂O reduced thermal NOx via dilution, the use of NH₃ as a dual role SWF - combined with a Recuperator-Reformer (59% NH₃-to-H₂ conversion) - delivered a 4% increase in total fuel energy and reduced NOx emissions across all tested NH₃ injection levels. The R2SCE system level comparison between 6%Vol NH₃ and diesel-only operation showed 10% and 43% reduction in BSFC and CO₂ per unit work, with NOx within maritime regulatory targets with typical after-treatments. These quantified outcomes serve as reference points for performance benchmarking, demonstrating how, compared to a contemporary conventional engine, the increased flexibility offered by the novel R2SCE concept can maximise fuel-to-power conversion for zero-carbon fuels.
Wylie, Elisa, Panesar, Angad
Investigation on Thermal Management of Heavy-Duty Commercial FCEV with Focus on Vehicle System Efficiency2025-01-02657/2/2025
The primary approach to meet the objectives of the EU Heavy Duty CO2 Regulation involves decarbonizing the road transport sector by battery electric vehicles (BEV) or hydrogen-fueled vehicles. Even though the well-to-wheel efficiency of hydrogen-fueled powertrains like fuel cell electric vehicles (FCEV) and H2-internal combustion engines (H2-ICE) is much lower in comparison to BEV, they are better suited for on-road heavy-duty trucks, long haul transport missions and regions with scarce charging infrastructure. Hence, this paper focuses on heavy-duty FCEVs and their overall energetic efficiency enhancement by intelligently managing energy transfer across coolant circuit boundaries through waste heat recovery, while ensuring that all relevant components remain within required temperature boundaries under both cold and hot ambient conditions. Results were obtained using a 1D-model that comprises all thermal fluid circuits (refrigerant, coolant, air) created through GT-Suite software. This model was utilized to simulate heat distribution during various road transport missions, such as alpine crossing via Brenner Pass from Munich (Germany) to Modena (Italy). Depending on load cycle profile and ambient conditions significant fuel savings were demonstrated. Furthermore, by coupling the high-temperature circuit of the fuel cell with the low-temperature circuit of the battery via a water/water heat exchanger, there is no need for additional electric heating via an electric heating element (PTC) within this circuit. In more extreme ambient conditions, utilizing recovered heat solely from high-temperature fuel-cell circuit is not sufficient; thus, cabin heating (HVAC) requires further measures such as an additional PTC or system heat pump to achieve an acceptable pull-up time of the cabin.
Uhde, Sophia, Langhorst, Thorsten, Wuest, Marcel, Naber, Dirk
PRODUCT BRIEFS25TOFHP04_114/1/2025
Modeling and Simulation Analysis of an Electric Vehicle in Cold Ambient Conditions: Energy Consumption and Impact of Battery Heating on Driving Range2025-01-81424/1/2025
Thanks to greatly increased energy density of battery, the average driving range of an electric vehicle has been advanced quite a lot. However, drastic reduction of driving range in cold ambient conditions still greatly restricts the wide application of electric vehicles. This paper presents a methodology of establishing multi-discipline coupled full vehicle model in AMESim to investigate the energy consumption of a pure electric vehicle in cold ambient conditions. Different strategies of battery heating through Positive Temperature Coefficient (PTC) part and/or combination of Motor Waste Heat Recovery (MWHR) were also investigated to study whether there is an improvement of driving range. Firstly, basic framework of the full vehicle model established in AMESim was introduced. Next, modeling details of individual sub-systems were illustrated respectively. Then, full vehicle energy consumption test was carried out in -7°C ambient condition to check the simulation accuracy. Finally, a variety of battery heating strategies parameterized by heating threshold X and Coefficient of Performance (COP) were investigated to study the effects of improvement of driving range. On the whole, simulation results of energy consumption and driving range are in good agreement with experimental data. In architecture 1, no PTC heating or only PTC heating (COP=1) was considered, the optimum X was found at 10°C, middle of a search interval of [0°C, 20°C]. The corresponding driving range is 237.177km, which is nearly 2km longer than that of base scheme, namely no PTC heating. In architecture 2, which accounts for a virtual heat pump (COP=2), the optimum X was found at 25°C, near the border of specified [0°C, 30°C] search scope. The corresponding driving range is 282.191km, and a range enhancement of 9.64km was acquired compared to the basic scheme of no heating. However, as to the actual architecture that using PTC and/or MWHR, a solely utilization of MWHR was foun to be the optimum, in other words, PTC heating in advance of MWHR has no benefit to the improvement of driving range.
Zhou, Shuai, Liu, Huaiju, YU, Huili, Yan, Xu, Yan, Junjie
Development of Composite PCM To Enhance Heat Transfer Rate with the Addition of Nanoparticles in Thermal Energy Storage2025-28-00232/7/2025
This paper explores the augmentation of thermal conductivity in paraffin wax through the incorporation of aluminum oxide (Al2O3) and copper oxide (CuO) nanoparticles, leading to the development of composite phase change materials (PCMs). The objective is to enhance heat transfer rates, crucial for various energy storage applications including industrial waste heat recovery and solar thermal energy storage. Differential Scanning Calorimetry (DSC) testing was employed to experimentally investigate the thermal properties of the resulting nanocomposite PCM. The experimental results reveal that the nanocomposite PCM, composed of 96.14% paraffin wax, 2% aluminum oxide, and 1.6% copper oxide, exhibits 1.35 times increase in heat transfer rate compared to conventional paraffin wax. The integration of nanoparticles into the PCM matrix, facilitated by a magnetic stirrer at 50oC for 4 hours, results in uniform distribution and improved grain morphology, as evidenced by SEM images. Moreover, the composite PCM demonstrates superior performance, surpassing paraffin wax by 1.35 times durin g heating and 1.5 times during cooling, while maintaining similar peak temperatures. The normalized enthalpy of the composite PCM exceeds that of paraffin wax by 1.25 times, highlighting enhanced energy storage capacity. The significant enhancements in thermal conductivity and phase change behavior are attributed to the presence of aluminum oxide and copper oxide nanoparticles. Notably, an optimized composition comprising 96.15% paraffin wax, 2.15% aluminum oxide, and 1.7% copper oxide Considered by mass demonstrates a delicate balance between improved thermal properties and material stability. This study underscores the immense promise of nanoparticles – enhanced composite PCMs as a transformative solution for enhancing thermal energy storage efficiency, with implications for sustainable energy technologies. The results shows that the thermal conductivity improved by 48% and the enthalpy increased by 25%.
Tarigonda, Hariprasad, Kumar, YB Kishore, Kala, Lakshmi K, R L, Krupakaran
Fusion Control Strategy Based on Rule and Dynamic Objective of Heat Pump Type Thermal Management System for Electric Vehicles2025-01-70231/31/2025
Thermal management system of electric vehicles (EVs) is critical for the vehicle's safety and stability. While maintaining the components within their optimal temperature ranges, it is also essential to reduce the energy consumption of thermal management system. Firstly, a kind of architecture for the integrated thermal management system (ITMS) is proposed, which can operate in multiple modes to meet various demands. Two typical operating modes for vehicle cooling in summer and heating in winter, which utilizes the residual heat from the electric drive system, are respectively introduced. The ITMS based on heat pump enables efficient heat transfer between different components. Subsequently, an ITMS model is developed, including subsystems such as the battery system, powertrain system, heat pump system and cabin system. The description of modeling process for each subsystem is provided in detail. The model is tested under world light vehicle test cycle (WLTC) condition of six different temperature groups to validate its feasibility. Next, a dynamic objective control strategy is proposed. It divides the operating condition into multiple time steps, where at each step, non-dominated sorting genetic algorithm II (NSGA-II) algorithm is employed to perform multi-objective optimization of cabin temperature, battery temperature, and state of charge (SOC). Different objectives are prioritized at different stages to achieve dynamic objective control. A fusion control strategy is developed by combining rule-based control with dynamic objective control. Finally, a comparative validation of the three control strategies—rule-based control, multi-objective control, and fusion control—is conducted under 40°C conditions. The results indicate that the designed thermal management system is effective. The fusion control strategy not only achieves desirable temperature control of each subsystem but also achieve energy reduction to a certain extent, which also alleviates range anxiety.
Zhao, Luhao, Tan, Piqiang, Yang, Xiaomei, Yao, Chaojie, Liu, Xiang
Modeling and Simulation Analysis of Thermal Management System for Hydrogen Fuel Cell Vehicle2025-01-70911/31/2025
An effective vehicle integrated thermal management system (ITMS) is critical for the safe and efficient operation of proton exchange membrane fuel cell (PEMFC) vehicles. This paper takes a fuel cell vehicle (FCV) as the research object, comprehensively considers the vehicle layout environment and thermal management requirements, and designs a complete thermal management system for FCV. The key components are selected and designed to match the performance and the control strategy of ITMS of fuel cell vehicle is developed. To do that, the ITMS model is established based on the heating principle and heat transfer theory of each key component. Then, the ITMS under Worldwide Harmonized Light Vehicles Test Cycle (WLTC) operating conditions at different ambient temperatures are simulated and analyzed by selecting indicators such as coolant flow rate and temperature. Under the ambient temperature of 40°C, the temperature of PEMFC is basically stable between 78 °C and 83°C, the coolant outlet temperature of the electric drive system radiator is lower than 65°C, and the temperature of the power battery and the crew compartment is maintained at about 25 °C and 23°C, respectively. In addition, in order to improve the performance of the vehicle in low temperature environment, the feasibility of waste heat recovery of the stack is also simulated. The results show that the ITMS has sufficient cooling capacity, and the temperature of key components remains stable under the controlled requirements under different working conditions. In winter, the waste heat generated by the stack can be used to heat the crew cabin. The proposed thermal management system can provide some design ideas and modeling methods for the future research and development of the thermal management system of fuel cell vehicles.
Jiang, Qi, Xiong, Shusheng, Wang, Yupeng, Zhu, Shaopeng, Chen, Huipeng
Efficiency Analysis of Hydrogen Internal Combustion Engine Power Generation System Based on Organic Hydrogen Storage Solution2025-01-71171/31/2025
Organic solution is an ideal hydrogen storage and transport carrier, and the dehydrogenation of solution is an endothermic process. High dehydrogenation heat demand becomes a key factor restricting its application. Hydrogen internal combustion engine (HICE) is an ideal power device under the current background of emphasizing clean and low carbon. In this study, dibenzyltoluene (DBT) was selected as liquid organic hydrogen carrier (LOHC), the residual heat of engine exhaust was used as the heat source of organic solution dehydrogenation, and the residual heat of engine exhaust is used as the heat source of organic solution dehydrogenation, using the combustion of dehydrogenated hydrogen products to supplement the heat absorption of hydrogen released by organic solution. Taking hydrogen internal combustion engine power generation as the application scenario, the power generation system of liquid organic hydrogen storage solution combined with hydrogen internal combustion engine (LOHC-HICE) is designed and the system calculation model is built. The system efficiency changes and the influence of subsystem modules on the system during the transfer of hydrogen internal combustion engine from 800 to 2000 are comprehensively analyzed. Waste heat accounted for about 20% of the heat consumed in dehydrogenation, up to 26% at 2000 RPM. Hydrogen combustion energy was the main contributor to dehydrogenation heat, accounting for 60-70%. Comprehensive and comparative analysis was made on measures to improve waste heat utilization, such as improving heat exchange efficiency, increasing exhaust temperature and reducing reaction temperature, and it was concluded that controlling reaction temperature at a lower level was the most feasible. The benefits to the system are most obvious. Improving the process of dehydrogenation of compressed hydrogen and organic solution and reducing the reaction temperature are the key to maintain self-dehydrogenation in the practical application of hydrogen combustion engine.
Zhang, Yulong, Luo, Qinghe, Sun, Baigang, Tang, Hongyang
Design and Performance Optimization of Automotive Thermoelectric Generator System Integrated with Heat Pipes2025-01-70601/31/2025
In the field of static power generation, thermoelectric technology has become an important solution for utilizing automotive exhaust waste heat. This study presents a new design for a heat exchanger integrated with heat pipes, aimed at augmenting the installation area of thermoelectric modules and improving the hot end temperature by high heat transfer rate. Moreover, the number of heat pipes in each region is optimized to reduce the temperature gradient along the direction of exhaust flow and maximize overall output performance. A comprehensive numerical model of the thermoelectric generator system is developed to conduct the performance prediction and parameter optimization. The results reveal that the integration of heat pipes substantially boosts the performance of the automotive thermoelectric generator system, characterized by enhanced heat transfer, increased power output, and improved conversion efficiency. And the optimization yields an optimal configuration with 5 heat pipes per thermoelectric module. Under the test conditions of an exhaust temperature of 600 K and a mass flow rate of 30 g/s, the new automotive thermoelectric generator system demonstrated an output power of 146.28 W and an output voltage of 166.26 V. These outputs represent a remarkable increase of 53.76% and 75.16%, respectively, compared to the conventional one without heat pipes. This work not only underscores the potential of heat pipe integration in thermoelectric systems but also offers a foundational framework for the optimal design of automotive thermoelectric generator systems equipped with heat pipes.
Zhao, JinFu, Ding, Renkai, Chen, Jie, Wang, Ruochen, Luo, Ding
Research on the Characteristics of an Integrated Thermoelectric Generation, Catalytic Conversion, and Noise Suppression System2025-01-70621/31/2025
In the context of global energy shortages and increasing environmental pollution, improving energy efficiency in automobiles has become a key area of research. Traditional internal combustion engines exhibit low energy conversion efficiency, with a significant portion of fuel energy wasted as exhaust heat. To address this issue, this paper proposes an integrated thermoelectric generation, catalytic conversion, and noise suppression system (ITGCMS) aimed at recovering waste heat from vehicle exhaust, while optimizing emissions and noise reduction through the combination of a catalytic converter and a muffler. A three-dimensional model was established using COMSOL software to thoroughly analyze the system's thermoelectric generation, catalytic conversion, and acoustic performance. The study found that Model B demonstrated the best thermoelectric performance, with an average surface temperature of 300.2°C and a more uniform temperature distribution across the thermoelectric modules. Additionally, Model B exhibited the highest catalytic conversion efficiency, with a flow velocity uniformity coefficient of 0.78 at the catalyst inlet, significantly outperforming the other models. Moreover, all three models showed effective noise reduction, particularly in the high-frequency range, and achieved better transmission loss across the entire frequency spectrum compared to traditional mufflers. Exhaust pressure loss increased with intake speed, but the differences between the models were minimal. Overall, Model B demonstrated the most comprehensive improvement in energy efficiency, emissions reduction, and noise optimization. This study provides a valuable theoretical basis and technical support for enhancing energy efficiency in the automotive industry, offering new directions for the future application of thermoelectric generation technology in vehicle exhaust systems.
Wu, Ji-Xin, Su, Chu-Qi, Wang, Yi-Ping, Yuan, Xiao-Hong, Liu, Xun
Experimental Study on the Thermoelectric Performance of PCM-TEG System2025-01-70671/31/2025
The integration of phase change materials (PCMs) with thermoelectric generators (TEGs) presents a solution to the challenge of unstable output resulting from fluctuations in the heat source. This study involved the establishment of an experimental test setup for PCM-TEG system to examine the impact of heat source power on the thermoelectric performance of PCM-TEG system. The results suggest that incorporating PCM effectively mitigates output voltage fluctuations, while higher heating power levels correspond to a notable extension in effective operational duration. In situations of low heat source power, incomplete PCM melting may lead to a significant decline in electricity generation during non-heating stages. Notably, the electricity generation during non-heating stages at 90 W heating power surpasses that at 30 W heating power by a factor of 11.78. Furthermore, the electricity generated during non-heating stages contributes to 22.4% of the total electricity generation. These findings have instructive implications for the development of PCM-TEG systems.
Tian, Meng, Wu, Fengyu, Zuo, Ao, Xuan, Zhiwei, Zhao, Yulong
Structure Design and Performance Enhancement of Automobile Thermoelectric Generator System Integrated with a Spoiler2025-01-70661/31/2025
The thermoelectric generator system is regarded as an advanced technology for recovering waste heat from automotive exhaust. To address the issue of uneven temperature distribution within the heat exchanger that limits the output performance of the system, this study designs a novel thermoelectric generation system integrated with turbulence enhancers. This configuration aims to enhance convective heat transfer at the rear end of the heat exchanger and improve overall temperature uniformity. A multiphysics coupled model is established to evaluate the impact of the turbulence enhancers on the system's temperature distribution and electrical output, comparing its performance with that of traditional systems. The findings indicate that the integration of turbulence enhancers significantly increases the heat transfer rate and temperature uniformity at the rear end of the heat exchanger. However, it also leads to an increase in exhaust back pressure, which negatively affects system performance. At lower exhaust flow velocities, the gains in output power attributable to the turbulence enhancers considerably outweigh the increases in exhaust back pressure. Specifically, under conditions of 550 K and 20 m/s, the output power, net output power, and temperature uniformity coefficient increase by 39.2%, 33.6%, and 8.5%, respectively. As exhaust temperature rises, the gains from the turbulence enhancers become even more pronounced. Nevertheless, under high flow conditions, the rise in exhaust back pressure can potentially degrade the system's net output performance. Therefore, it is recommended that exhaust flow be appropriately diverted in practical applications to ensure optimal performance. This research provides essential theoretical guidance for the design and performance optimization of automotive thermoelectric generation systems.
Chen, Jie, Ding, Renkai, Wang, Ruochen, Liu, Wei, Luo, Ding
Experimental and 1D Modeling Analysis of Thermoelectric Generation to Improve the Performance of Compressed Natural Gas Heavy-Duty Engines Used in Commercial 22-Ton Trucks13-06-03-00191/27/2025
A significant amount of chemical fuel energy in internal combustion engines is wasted through exhaust heat. Waste heat recovery (WHR) systems can transform the heat into electrical energy using thermoelectric generators (TEG). This work utilizes a 1D CFD model to demonstrate the potential of TEG-WHR in improving the thermal efficiency of mass-production, compressed natural gas (CNG) engines used in commercial 22-ton heavy-duty trucks. First, the TEG with heat exchanger experiments are performed to measure thermal and electrical performance data under different fin pitches and inlet gas conditions (Re number, temperature, gas flow rate). These data are used to develop and validate a TEG model, which considers user-defined functions of heat transfer and flow friction coefficients to reproduce measured thermal/electrical characteristics of the integrated TEG with its heat exchanger. The engine experiments are conducted based on the speed–torque map (51 test conditions) of the JE05 heavy-duty cycle using the turbocharged engine equipped with a multi-port injection system. The engine model is calibrated and validated against test data under base conditions (using production valve timings), optimal variable valve actuation (VVA), and variable compression ratio (VCR). Finally, the high-fidelity engine and TEG models are integrated to predict the electrical power generated by a compact TEG-WHR (three-layer, size: 1.3 × A4-paper). The integrated model considers a tradeoff between TEG-generated power and engine pumping loss. Simulation results show that the compact TEG can generate effective 20–701 W electrical powers, translating to about 0.03–1.07% brake thermal efficiency improvement.
Sok, Ratnak, Kusaka, Jin
Review on Integrated Thermal Management Systems of Electric Vehicles2024-28-022712/5/2024
Electric Vehicles use Li-ion batteries due to their high energy and power densities. Performance of Li-ion cell is sensitive to temperature. Temperature control of these batteries becomes very important to provide safety and performance under different working conditions. This paper review different integrated thermal management system developed for Electric Vehicles. integrated thermal management content. Battery thermal management, Cabin thermal management and Electric drive thermal management. These systems share some common objectives and common parts. Integration of these systems will help to optimize the number of components in the Electric Vehicles thermal management system. The integrated thermal management system also helps to optimize the weight and use of waste heat to heat the cabin or battery. This will help in optimization of energy consumed by the thermal management system and range improvement. Integrating different systems which content refrigerant and coolant circuit and different modes of the working makes the system complex. Different types of integrated thermal management system and their working modes, working of each subsystem with respect to whole system is reviewed.
Mhaske, Pramodkumar Chimaji
Efficiency Improvement in a 48-Volt Mild Hybrid Vehicle Using Rankine Cycle Waste Heat Recovery2024-01-431711/5/2024
The automotive industry faces significant obstacles in its efforts to improve fuel economy and reduce carbon dioxide emissions. Current conventional automotive powertrain systems are approaching their technical limits and will not be able to meet future carbon dioxide emission targets as defined by the tank-to-wheel benchmark test. As automakers transition to low-carbon transportation solutions through electrification, there are significant challenges in managing energy and improving overall vehicle efficiency, particularly in real-world driving scenarios. While electrification offers a promising path to low-carbon transportation, it also presents significant challenges in terms of energy management and vehicle efficiency, particularly in real-world scenarios. Battery electric vehicles have a favorable tank-to-wheel balance but are constrained by limited range due to the low battery energy density inherent in their technology. This limitation has led to the development of hybrid electric powertrains, which combine an efficient internal combustion engine with a battery electric powertrain. This paper presents the findings of a simulation study which examines the efficiency of a compact mild hybrid electric vehicle enhanced by a Rankine cycle unit. The unit employs an advanced bottoming Rankine cycle with a steam accumulator to recover exhaust heat from the internal combustion engine in a mild hybrid electric vehicle, thereby reintroducing the recovered energy into its electrical system. This potential was evaluated in a state-of-the-art Euro-6 reference vehicle with a mild hybrid powertrain to ascertain its feasibility in meeting the future European carbon dioxide and vehicle efficiency targets in the cost-sensitive C-segment mass vehicle sector. The resulting mild hybrid vehicle achieved an average vehicle efficiency of 40.84 % and a carbon dioxide figure of 93.1 g CO2/km in the Worldwide Harmonized Light Duty Test Cycle. This result demonstrates that the vehicle under investigation could exceed the European target average vehicle cycle efficiency.
Kraljevic, Ivica, Spicher, Ulrich
Computational and Experimental Evaluation of Thermoelectric Generator for Waste Heat Recovery in Internal Combustion Engine Applications2024-01-50768/5/2024
Much of the thermal energy derived from combustion of fuel is lost through exhaust gases. By effectively recovering waste heat energy in the form of electricity, it can be used to recharge batteries or power auxiliary systems thus improving both performance and fuel economy. In this work, the use of thermoelectric generators (TEG) for energy recovery were studied using both computational and experimental strategies. The efficiency of TEG (ȠTEG) was analyzed through computational methods by changing temperature gradients, Seebeck coefficient (α), and dimensions of the P- and N-type plates individually. The results of computational analysis showed that in comparison to vertical and planar configuration, mixed-type thermocouple delivered 83.3% and 96% more power, respectively. Raising the α, enhanced the ȠTEG by 57% and lowering α affected the ȠTEG by 9.5% for mixed thermocouples. A marginal development in the ȠTEG was achieved by increasing the length of the P- and N-type semiconductors but decreasing the length improved ȠTEG by more than 95%. In the experimental approach, the ȠTEG of a Peltier module-based TEG was studied under static and dynamic testing conditions on a motorcycle by connecting more than one module in series and parallel, respectively. The average power generated over a range of engine speeds was 10.9 W and 10.6 W for series and parallel configurations, respectively, under static test conditions. The average power obtained with dynamic tests was 10.5 W and 12.2 W for series and parallel configurations, respectively.
Chelladorai, Prabhu, Atekov, Parahat, Balakrishnan, Navaneetha Krishnan, Kashyap, A., Chakravarty, P., Naresh, G.
The Hybrid Concept of Turboshaft Engine Enhanced by Steam Cycle Using Waste Heat Recovery—Combined Analytical and Numerical Calculation of Its Efficiency03-17-06-00456/4/2024
The article presents a hybrid concept of a turboshaft engine that fits into the area of PGE (pressure-gained combustion). It combines the advantages and elements of a piston engine and a turbine engine. The combustion takes place in isochoric chambers. The proposed timing system of the engine efficiently realizes the Humphrey cycle. Additionally, the main gas cycle engine was enhanced by the Clausius–Rankine steam cycle to achieve effective power of engine equal to 1231.3 kW. It was supplied by waste heat recovery from the exhaust gas. The enhancement of the engine by the secondary steam cycle significantly improved engine effective efficiency with a final value reaching 0.446. The effective efficiency and specific fuel consumption of the engine were calculated using merged analytical–numerical CFD (computational fluid dynamics) analysis. The centrifugal compressor, gas turbine, and steam turbine can work on the common shaft whose rotational velocity is 35,000 rpm. Because of additional weight, it could have potential applications for stationary use or heavy military units.
Tarnawski, Piotr, Ostapski, Wiesław
WITHDRAWAL NOTICE2024-01-2591.014/9/2024
This paper has been withdrawn by the publisher because of non-attendance and not presenting at WCX 2024.
Investigating Route Gradient and Thermal Demand on Hydrogen Fuel Cell Electric Bus Energy Consumption2024-01-21764/9/2024
In 2022 in the UK, the transport sector was the largest single contributing sector to greenhouse gas emissions, responsible 34% of all territorial carbon dioxide emissions [1]. In the UK there is growing uptake in zero emission powertrain technologies, with the most promising variants based on battery electric or hydrogen fuel cell electric configurations. Given the limited number of fuel cell electric buses currently in operation in Europe, vehicle models and simulations are one of the few methods available to estimate energy consumption and provide the necessary increased confidence in operating range. This paper investigates the impact of route characteristics, thermal demand and coefficient of performance of different heat source configurations on the operational energy consumption of fuel cell electric buses. Using a MATLAB/Simulink model, the total energy demand of a vehicle operating in different route/elevation profiles is considered. The findings from this study show that implementing a waste heat recovery system, which recovers excess heat produced by the fuel cell system, in a traditional heat pump based HVAC system can reduce the amount of excess fuel consumption required for providing HVAC services by up to 70% over the course of a duty cycle, so long as high levels of waste heat can be recovered. It also shows that through the use of waste heat recovery systems it is possible to replace the heat pump based HVAC system with a much simpler positive temperature coefficient heater system and still achieve or improve upon the performance of a traditional heat pump based HVAC system.
O'Boyle, Conor, Blades, Luke Aubrey William, McGrath, Teresa, Early, Juliana, Harris, Andrew
On the Application of Joule-Cycle-Based Waste Heat Recovery to Heavy-Duty Vehicles2024-01-25894/9/2024
Internal combustion engines are becoming ever more efficient as mankind seeks to mitigate the effects of climate change while still maintaining the benefits that a mechanized society has brought to the global economy. As peak values, mass production spark-ignition engines can now achieve approximately 40% brake thermal efficiency and heavy-duty truck compression-ignition engines can approach 50%. While commendable, the unfortunate truth is that the remainder gets emitted as waste heat and is sent to the atmosphere to no useful purpose. Clearly, if one could recover some of this waste heat for beneficial use then this is likely to become important as new means of mitigating fossil CO2 emissions are demanded. A previous study by the authors has identified that the closed Joule cycle (or complications of it beginning to approximate the closed Ericsson cycle) could reasonably be developed to provide a practical means of recovering exhaust heat when applied to a large ship engine. In that previous work there was a sensitivity shown between overall pressure ratio and the ratio of specific heats of the gas being used as the working fluid and, providing those variables were appropriately chosen, relatively high efficiencies and specific work outputs appeared to be achievable. While marine engines might seem to be ideal applications for this technology, in no small part due to the effectively infinite and relatively low-temperature sink available at the bottom of the cycle, their low exhaust temperatures (arising from their inherently high efficiencies) and the existing placement of scrubbers and economizers in the exhaust gas run makes the practical application of waste heat recovery (WHR) more difficult on them; nevertheless, using real exhaust gas compositions, the previous work clearly showed some significant potential in that arena, even if the exact level of upper temperature available in the cycle is still unknown. Given the early indications that Joule-cycle based WHR could work in already-efficient marine applications, this paper investigates the practicality of such methods of recovering exhaust heat in another sector – heavy-duty road transport. In this application, the challenge of a more difficult rejection of heat to the atmosphere on the cold side of the cycle is offset by a hotter exhaust gas temperature. Versus light-duty applications, long-distance transport can offer the chance for more continuous operation with fewer transients to reduce average efficiency, plus a direct economic payback in the form of lower operating costs. To investigate this opportunity modelling was performed using data in the literature already published for a diesel-engined truck which was then input to one of the Joule-cycle-based WHR models already developed for the initial marine-based project. These results show that this WHR concept could usefully be applied to truck use. An open Joule cycle system is then proposed and this too is investigated; here an increased benefit was predicted because, unlike for the closed Joule cycle approach, the working fluid flow rate in the system can be varied over a wider range, and the final heat exchange is avoided, giving a reduced lower cycle temperature.
Turner, James, Kenkoh, Kesty Yong, Gubba, Sreenivasa, Vorraro, Giovanni
Use of Accurate Simulation Workflows to Optimize Waste Heat Recovery from Thermoacoustic Engines2024-01-25904/9/2024
Thermoacoustic heat engines convert heat into useful energy by generating acoustic waves from a heat source that can then be extracted as useful work. These engines are inexpensive, robust, versatile, and capable of extracting energy from a wide variety of heat sources ranging from waste heat from power plants to exhaust heat of vehicles. In this article, our investigation focuses on using simulation workflows to improve the performance of thermoacoustic engines. We begin with validating the workflows with published data for both traveling wave and standing wave thermoacoustic engines. Following that, we investigate the effect of changing the working fluid and the operating pressure to increase acoustic power. This study uses a coupled PowerFLOW™ and PowerTHERM™ methodology to simulate the buoyancy-driven flows that generate acoustic pressure waves. Good correlations were observed for both traveling and standing wave thermoacoustic engines. For the design iterations, the most improved design showed large improvements both in absolute power output and relative to the thermodynamic maximum of a Carnot cycle.
Mukutmoni, Devadatta, Powell, Robert, Kandasamy, Satheesh
Cost Effective Techniques for SCEV to Improve Performance & Life of Battery and Motor by Using Efficient Thermal Systems2024-26-02751/16/2024
The automotive world is moving towards electric powertrain systems. The electric powertrain systems have emerged as a promising alternative to the conventional powertrain system. The performance of electric vehicle is highly dependent on operating temperature of electric and electronic components of the vehicle. All power electronics and electric components in EV generate heat during operation and it must be removed to prevent overheating of components. Higher temperatures raise safety concerns whereas lower temperatures deteriorate the performance of power electronics & electric components. These power electronics & electrical components perform efficiently and safely if operated within certain temperature range. This paper presents an advanced efficient cost-effective thermal technique for small commercial electric vehicle (SCEV) to improve the performance & life of major electric components. It is observed from literature survey that this is a novel technology for small commercial electric vehicles. The one-dimensional (1D) simulation approach is employed to evaluate the performance of the existing thermal management systems for battery, motor, cabin and power electronics cooling & heating during various charging and discharge modes at different ambient temperature conditions. Further, advanced efficient cost-effective thermal management techniques are proposed and analysed by 1D simulation approach. The proposed thermal management techniques consist of simple and cost-effective thermal architectures having 3-way & 4-way valves which helps to recover waste heat, reduces compressor duty cycle and improve the overall vehicle performance in terms of range improvement or battery downsizing to achieve the same range. Simulations performed for new technique show that the combination of these techniques can significantly improve the thermal behaviour of the battery & electric motor as well as the range of the vehicle by 4 - 5 km. Also, it will improve the life of battery and motor. The additional cost of 3-way & 4-way valve at vehicle level will get recover within short duration of time compared to vehicle life. Furthermore, the cost-effectiveness of the proposed thermal management system is demonstrated, making it a viable solution for all electric small commercial vehicles. This study provides valuable insights for the design and development of efficient and cost-effective thermal management systems for small commercial electric vehicles.
Chormule, Suhas Rangrao
Turbo Compounding of a Naturally Aspirated Single Cylinder Diesel Engine – A Simulation and Experimental Study2023-01-184510/24/2023
Almost one-third of the fuel energy is wasted into the atmosphere via exhaust gas from an internal combustion engine. Despite several advancements in waste heat recovery technology, single-cylinder engines in the market that are currently in production remain naturally aspirated without any waste heat recovery techniques. Turbocharging is one of the best waste heat recovery techniques. However, a standard turbocharger cannot be employed in the single-cylinder engine due to technical challenges such as pulsated flow conditions at the exhaust, phase lag in the intake and exhaust valve opening. Of late, the emphasis on reducing exhaust emissions has been a primary focus for any internal combustion engine manufacturer, with the onset of stricter emission norms. Thus, the engine designer must prioritize emission reduction without compromising engine performance. Current work focuses on enhancing the power output of a 0.6-litre, single-cylinder naturally aspirated diesel engine by employing a power turbine. Since the exhaust flow conditions were pulsated, an impulse turbine was employed. One-dimensional simulation studies were carried out after validating the base naturally aspirated engine model. An impulse turbine was designed and simulated for the pulsated flow conditions. Simulation results show that the single-cylinder naturally aspirated engine delivered a superior performance with turbo compounding. The brake power output of the turbo-compounded engine improved by 6% compared to the base NA version. Also, the thermal efficiency of the turbo-compounded engine improved by 2%. HC emissions were reduced by 31% and CO emissions by 11% for the turbo-compounded engine. Soot emissions were 2% lower, and NOx emissions were 5% lower for the turbo-compounded engine than the base naturally aspirated engine. Thus, turbo-compounding is an effective waste heat recovery system that improves the performance and reduces exhaust pollutants of a single-cylinder naturally aspirated engine.
Ramkumar, J, Krishnasamy, Anand, Ramesh, A
Insights into combustion and performance of HCCI engine fed with PODE 1 and H 2 -rich PODE 1 -reformate2023-32-00049/29/2023
A transition to sustainable energy sources, carbon- free/neutral energy carriers and efficient combustion technologies is intensively discussed as a key pathway in achieving a greener, more secure energy future. In particular, enhancement of internal combustion engine (ICE) performance using promising alternative carbon- neutral propellants, waste heat recovery (WHR) and state-of-the-art combustion methods has gained high research attention. Polyoxymethylene dimethyl ethers (PODEn, OMEn), well-suited for compression-ignition (CI) combustion, arouse strong interest as potentially sustainable and cleaner alternatives to diesel fuel. This study reports for the first-time numerically examined combustion performance characteristics of reforming- controlled compression ignition (RefCCI) ICE engine, managed by mixing of polyoxymethylene dimethyl ether 1 (PODE1) and its hydrogen-rich reforming products (PODE1-reformate) obtained through thermo- chemical recuperation. The results showed that the RefCCI combustion-control is possible by maintaining an appropriate H2/PODE1 ratio in the process of in- cylinder mixing of PODE1 and PODE1-reformate prior to auto-ignition. Beneficial high engine efficiencies of 40.6-48.4% and reduced NOx and CO emissions were achieved at the examined compression ratio of 16.
Buntin, Denis, Tartakovsky, Leonid
Efficiency Improvement of Heat Pump for Low Ambient Conditions Using Waste Heat from Electrical Vehicle Traction Motor2023-28-00139/14/2023
Electric vehicles (EV) have become very significant and potential way to reduce greenhouse gas emissions on a worldwide scale. EV also provides Energy security, as it reduces the dependency on petroleum producing countries of the world. Similar to the conventional Internal Combustion Engine Cars, in Electrical Vehicles also the efficient air conditioning system is very important for providing thermal comfort and for giving safe driving conditions. In Air Conditioning systems for EV, the heating option is available in the form of Electrical heaters and Heat Pump systems. The Heat pumps have become more popular compared to the electrical Positive Temperature Coefficient (PTC) heaters because of their highly efficient and energy saving designs. However, there are still some issues with using heat pumps. One of such issue is their less Coefficient of performance (COP) at low ambient conditions. Experimental results also show that the driving range decreases by using the electric heating system in vehicles. This paper presents a study on the solutions for increasing the efficiency of heat pump at low ambient conditions. The waste heat coming out from the Traction Motor and power electronics of Electric Vehicles is being utilized for increasing the temperature of Air, which is entering the condenser in Heating mode. This has been done using a heat Exchanger placed in front of the condenser. The study is being evaluated using Coil Designer software for component level simulations and further for the system level simulations, the Kuli software has been used. The study has also resulted in increasing the COP of the system in the Heating Mode.
Dagar, Aakash, Sharma, Nishant, Suman, Saurabh, Kushwah, Yogendra Singh
A Novel Way to Convert Heat to ElectricityTBMG-489339/1/2023
Researchers at the National Institute of Standards and Technology (NIST) have fabricated a novel device that could dramatically boost the conversion of heat into electricity. If perfected, the technology could help recoup some of the recoverable heat energy that is wasted in the U.S. at a rate of about $100 billion each year.
Direct and Indirect Exhaust Heat Recovery from Turbocharged Heavy-Duty Engine2023-24-01228/28/2023
Waste Heat Recovery (WHR) is one of the most viable opportunities to reduce fuel consumption and CO2 emissions from internal combustion engines in the transportation sector. Hybrid thermal and electrical propulsion systems appear particularly interesting because of the presence of an electric battery that simplifies the management of the electrical energy produced by the recovery system. The different technologies proposed for WHR can be categorized into direct and indirect ones, if the working fluid operating inside the recovery system is the exhaust gas itself or a different one whose sequence of transformations follows a thermodynamic cycle. In this paper, a turbocharged diesel engine (F1C Iveco) equipped with a Variable Geometry Turbine (VGT) has been tested to assess the energy recoverable from the exhaust gases both for direct and indirect recovery. A direct technology based on an auxiliary turbine placed in the exhaust pipe (turbo-compounding) has been considered and compared with an Organic Rankine cycle (ORC)-based recovery unit fed by the exhaust gases. A model-based comparison between the two technologies has been assessed in this paper. The input data were the result of an experimental campaign done on the exhaust gases of the F1C Iveco operated on a high-speed dynamometer test bench. Data on exhaust gas properties, turbocharger equilibrium and engine performances were collected for a wide range of engine operating conditions. Concerning the ORC-based power unit, the model uses the significant research experience done on the sector that set up the most relevant machine performances (expander and pump efficiency, engine backpressure produced, pinch points at the two heat exchangers) so giving the model high reliability. Preliminary data on a turbo-compounding system operated on the same engine were also measured so resolving the most important uncertainties of the recovery unit (engine backpressure produced, turbine and electrical generator efficiency, matching between the turbocharging unit). A preliminary assessment of the overall potential recovery when both technologies were present has been done, focusing the attention on heavy-duty engines.
Di Bartolomeo, Marco, Di Battista, Davide, Fatigati, Fabio, Cau, Giorgio, Cipollone, Roberto
Waste Exhaust Heat Recovery in Diesel Engine by Using Optimum Design and Rankine Cycle2023-01-09444/11/2023
The waste heat recovery (WHR) system appears to lower overall fuel consumption of the engine by producing additional power and curtailing greenhouse emissions per unit of power produced. In this project, a 25.5 kW diesel engine is used and simulated, which has an exhaust temperature of about 470°C. During optimization of the heat exchangers, the overall weight of the heat exchangers is kept low to reduce the final cost. Additionally, the overall pressure drops across the superheater, boiler, and economiser are kept at around 200 kPa to expel the exhaust gas into the atmosphere easily. To accomplish high heat-transfer across the heat exchangers, the pinch temperature of the hot and cold fluids is kept above 20°C. In this project, under the design constraints and available heat at the exhaust gases, the WHR system has enhanced the power and reduced the break specific fuel consumption by around 6.2% and 5.8%, respectively at 40 bar pressure. The maximum net power produced is around 1.5 kW at 40 bar steam pressure. All thermodynamic equations have been set up and solved with the help of Engineering Equation Solver (EES) software to meet the manufacturer’s requirements such as the length of heat exchangers, the number of the tubes and rows, and the gap between the tubes, thickness of tubes, and materials. In the last, the cost of all required components is considered. The cost of the entire WHR system is calculated at around $14,220 and the payback period is around 4 years and 5 months.
Bari, Saiful, Randhawa, Tejpal
A Synergic Use of Innovative Technologies for the Next Generation of High Efficiency Internal Combustion Engines for PHEVs: The PHOENICE Project2023-01-02244/11/2023
Despite the legislation targets set by several governments of a full electrification of new light-duty vehicle fleets by 2035, the development of innovative, environmental-friendly Internal Combustion Engines (ICEs) is still crucial to be on track toward the complete decarbonization of on road-mobility of the future. In such a framework, the PHOENICE (PHev towards zerO EmissioNs & ultimate ICE efficiency) project aims at developing a C SUV-class plug-in hybrid (P0/P4) vehicle demonstrator capable to achieve a -10% fuel consumption reduction with respect to current EU6 vehicle while complying with upcoming EU7 pollutant emissions limits. Such ambitious targets will require the optimization of the whole engine system, exploiting the possible synergies among the combustion, the aftertreatment and the exhaust waste heat recovery systems. Focusing on the first aspect, the combined use of innovative in-cylinder charge motion, Miller cycle with high compression ratio, lean mixture with cooled EGR and electrified turbocharger will enable a highly diluted combustion process capable to achieve a peak indicated efficiency of 47% and, at the same time, to minimize the engine out emissions. Numerical simulations were intensively exploited to reduce the engine calibration time and to preliminary assess the benefits of the abovementioned technologies. In particular, 3D-CFD simulations highlighted the capabilities of the SwumbleTM intake ports to produce an increase of about 50% of the Turbulent Kinetic Energy (TKE), while 1D-CFD models showed possible further enhancements of the brake thermal efficiency through the use of the new turbocharger (+2%) and of an aggressive Millerization of the cycle (+1.1%). Finally, a preliminary experimental campaign, performed on the first engine prototype, confirmed the encouraging results of the simulation activity. With an AFR = 1.43 and an EGR ratio close to 5%, the PHOENICE engine showed a further improvement in the BTE up to 4% and a simultaneous reduction of the NOx emissions of more than 70% in comparison with conventional stoichiometric, undiluted operation.
TAHTOUH, Toni, Millo, Federico, Rolando, Luciano, Castellano, Giuseppe, Brignone, Mauro, Cleeton, Jason, Demeilliers, Nicolas, Lucignano, Gennaro, Sierra Castellanos, Juan, Perazzo, Alessandro
Application of Model Predictive Control to Cabin Climate Control Leading to Increased Electric Vehicle Range2023-01-01374/11/2023
For electric vehicles (EVs), driving range is one of the major concerns for wider customer acceptance and the cabin climate system represents the most significant auxiliary load for battery consumption. Unlike internally combustion engine (ICE) vehicles, EVs cannot utilize the waste heat from an engine to heat the cabin through the heating, ventilation and air conditioning (HVAC) system. Instead, EVs use battery energy for cabin heating, this reduces the driving range. To mitigate this situation, one of the most promising solutions is to optimize the recirculation of cabin air, to minimize the energy consumed by heating the cold ambient air through the HVAC system, whilst maintaining the same level of cabin comfort. However, the development of this controller is challenging, due to the coupled, nonlinear and multi-input multi-output nature of the HVAC and thermal systems. Furthermore, the controller must satisfy different control requirements by leveraging multiple control actuators whilst simultaneously respecting multiple control and system constraints. A Model Predictive Controller has been used to reduce the control complexity of a conventional controller that requires many heuristic control laws and significant calibration effort. The control solution has been realised for an industrialized application, respecting typical embedded control hardware solutions, minimizing computational effort and memory requirements. This paper introduces a development approach utilizing Adaptive Model Predictive Control (AMPC) to address the challenges above, leading to the demonstration in a vehicle (Jaguar I-PACE) over the UDDS cycle on a climatic chassis dynamometer. The structured development approach improves the efficiency and flexibility of setting-up advanced control solutions.
Fussey, Peter, Ma, He, Dutta, Nilabza
Simulation of the use of Organic Rankine Cycle (ORC) to reduce fuel consumption in locomotives on Brazilian railroads2022-36-00882/10/2023
According to the International Energy Agency, of world energy consumption, fuel oil and natural coal, as primary sources of energy for some process, correspond to about 60% of the total. This consumption has been increasing for decades, mainly in the transport sector, including railways. In Brazil, in 2019, the transport sector represented 32.7% of energy consumption. At VLI Logística, a company that operates 7,000 km of railways in Brazil, consumption in 2020 was 203 million litres of diesel, which generated a cost of US$ 86 million. In this context, it is necessary to increase energy efficiency in the sector and, for this, the feasibility of recovering waste heat from the internal combustion engine (ICE) of a locomotive must be verified. The present study was carried out considering a GE 7FDL engine, 16 cylinders, turbocharged, with water cooling and 4,020 HP (2,998.92 kW) of power. The simulations of ORC cycles, using the cooling water system and the exhaust gases of the ICE, developed in the Engineering Equation Solver (EES), point to a heat recovery capacity that can generate up to 10% of the electrical power of the ICE, with the cooling water system generating 89.9 kW, and the exhaust gas system producing 271.9 kW. Applying an arrangement with preheating, using the 2 systems, the generated power reached 314.4 kW. Fuel savings can reach 9.44%, depending on the locomotive's operating time at each acceleration point. Regarding the economic viability, the internal rate of project return was 3.10%. The payback time on invested capital was 20.4 years. Even after a sensitivity analysis of the economic viability of the project in relation to the price of diesel and the exchange rate of the Dollar, none of the ORC arrangements studied presented results that adhered to the indicators adopted for new projects in the VLI.
dos Santos Juvencio, Rondinelli, Martins Cunha, Carla Cesar, Conceição Soares Santos, José Joaquim
Printed Thermoelectric Generators for Power GenerationTBMG-473271/1/2023
Thermoelectric generators (TEGs) convert ambient heat into electrical power. They enable maintenance-free, environmentally friendly, and autonomous power supply of the continuously growing number of sensors and devices for the Internet of Things (IoT) and recovery of waste heat. Scientists have now developed three-dimensional component architectures based on novel, printable thermoelectric materials.
Research on Modeling and Control of Fuel Cell Vehicle Integrated Thermal Management System15-16-02-000912/6/2022
The heat pump system has the advantages of high heating efficiency and low energy consumption and is more and more widely used in vehicles. In order to improve the economy and thermal management effect, this article introduces the heat pump system into the fuel cell vehicle thermal management system, designs the fuel cell vehicle integrated thermal management system (VITMS), and conducts research. First, the temperature control objectives of each subsystem are determined, the refrigeration and heating schemes of the integrated thermal management system are designed, and the working state and pipeline design of system components under different working modes are clarified. Then the modeling is carried out according to the working mechanism of the key components in the thermal management system and the corresponding control strategy is proposed for the key components in the VITMS. The simulation tests of the thermal management system at different temperatures are carried out to verify the rationality and efficiency of the established scheme and the influence of different heating methods on vehicle economy is compared. The simulation results show that the proposed VITMS can make the temperature of the passenger compartment reach and maintain the target temperature range in a short time in both high-temperature and low-temperature environments. Compared with positive temperature coefficient (PTC) heating, the economy is improved by 20.9% when the heat pump system is used for heating without the fuel cell waste heat recovery. And the economy is improved by 25.5% when the heat pump system is used for heating and the fuel cell waste heat recovery is adopted.
Zeng, Xiaohua, Wang, Shupeng, Song, Dafeng, Ning, Jing
Development of 10kW Proton Exchange Membrane Fuel Cell Combined Heat and Power System for Domestic Building Services2022-01-703610/28/2022
Cogeneration equipment based on hydrogen proton exchange membrane fuel cell has become one of the most economical and flexible low-carbon distributed power supply equipment, which has been widely concerned in scientific research and commercial promotion. The optimized integration of the system is the key step to realize commercialization. This paper focuses on the analysis of the technical status of the key components of combined heat and power (CHP) system and put forward the theoretical design method and operation strategy of each subsystem for a 10kW CHP system based on PEMFC. Firstly, for the air supply subsystem, it was found that when the back pressure valve was placed behind of the membrane humidifier, the air humidity of stack inlet increased gradually with the increase of current density, which presented a contrary trend from that at the front. The pressure difference inside the membrane humidifier was obviously reduced. Secondly, in addition to recovering the waste heat from coolant, an operation strategy that preheating the coolant by stored hot water was proposed, which helped to save the system cost due to coolant heater and improve the overall efficiency. The construction of the 10kW CHP system in this paper provides a guidance for the design and integration of CHP system based on PEM fuel cells.
Ma, Tiancai, Li, Ruitao, Gao, Te, Meng, Yixun, Liang, Yonghao
Items per page:
1 – 50 of 335