Browse Topic: Greenhouse gas emissions

Items (1,235)
The energy transition initiatives in Germany’s renown coal mining region Lusatia have driven research into Power-to-X-to-Power technologies, where synthetic fuel is produced from renewably sourced hydrogen and captured CO2, and converted to electricity and heat through oxyfuel combustion. This work investigates the multi-objective optimization of oxyfuel gas engine using a stochastic engine model and detailed chemistry. Exhaust gas recirculation (EGR) rate, initial cylinder temperature and pressure, spark timing, piston bowl radius and depth are selected as design parameters to minimize the exhaust temperature at exhaust valve opening and indicated specific fuel consumption (ISFC) corresponding to oxyfuel operation with different dry and wet EGR rates. The optimization problem is solved for a dry EGR and four wet EGR cases with various CO2/H2O fractions, aiming to achieve comparable performance as in conventional natural gas / air operation, and energy-efficient carbon capture. The
Asgarzade, RufatFranken, TimMauss, Fabian
In the present work, the effect of HHO addition to gasoline was investigated using HHO produced via the HydroBoost™ electrolysis technology—a system specifically designed to overcome the limitations of conventional electrolysis methods, such as electrode degradation, low efficiency, and safety concerns. Engine performance, fuel behavior, and emission characteristics were evaluated both with and without HHO enrichment. A comprehensive four-phase testing protocol was adopted to simulate various real-world driving conditions. Through a multi-parameter assessment—including fuel economy (FE), engine response under different load conditions, fuel savings accounting for parasitic load, total volatile organic compounds (TVOC), and greenhouse gas (GHG) emissions—it was demonstrated that HHO addition significantly enhances both the performance and emission characteristics of a gasoline-powered internal combustion engine. Statistical significance of these parameters was assessed across four
Sherman, GregorySingh, Amit Pratap
Amid escalating global warming challenges, the aviation industry must adopt low-carbon and green practices. China, aiming to meet its dual carbon goals, urgently requires enhanced research and development in sustainable aviation fuels (SAF), including their sustainability certification. However, China’s regulatory framework and limited research foundation in biofuels exacerbate this endeavor. This article summarizes the development status of SAF sustainability certification internationally and within China, encompassing the indicator framework, full life cycle greenhouse gas (GHG) calculation methodologies, and emission reduction thresholds. It also highlights issues encountered in the application of current international sustainability certification systems in China, such as high certification costs and inadequate data security. Advancement in domestic sustainability certification in China faces obstacles related to the incomplete foundational database, despite possessing life cycle
Zhang, ShupingHe, YinJia, QuanxingJia, QinTao, ZanMiao, JiaheShi, YaoZhang, XiangpingWang, Siyu
Off-highway vehicles (OHVs) in sectors such as mining, construction, and agriculture contribute significantly to global greenhouse gas (GHG) emissions, particularly carbon dioxide (CO₂) and nitrogen oxides (NOₓ). Despite the growth of alternative fuels and electrification, diesel engines remain dominant due to their superior torque, reliability, and adaptability in harsh environments. This paper introduces a novel onboard exhaust capture and carbon sequestration system tailored for diesel-powered OHVs. The system integrates nano-porous filters, solid-state CO₂ adsorbents, and a modular storage unit to selectively capture CO₂ and NOₓ from exhaust gases in real time. Captured CO₂ is then compressed for onboard storage and potential downstream utilization—such as fuel synthesis, carbonation processes, or industrial sequestration. Key innovations include: A dual-function capture mechanism targeting both CO₂ and NOₓ Lightweight thermal-regenerative adsorption materials Integration with
Vashisht, Shruti
Alcohol fuels are regarded as a feasible approach to address rising energy demands and reduce the dependency on fossil fuels, with ethanol and methanol emerging as a promising renewable fuel for spark-ignition engines. In this research work, tests were performed on a spark ignition engine altered from a diesel engine that employs ethanol/methanol-gasoline blend as fuel operating under lean conditions. The experiments were conducted at 10.5:1 compression ratio and 1500 rpm under full throttle condition with three fuel blends namely M10 (10% of methanol+ 90% gasoline), E10 (10% of ethanol+ 90% gasoline), E5M5 (5% of each ethanol and methanol+ 90% gasoline). Investigational results reveals that alcohol-gasoline blends displayed low COV of IMEP. Furthermore, the alcohol-gasoline mixtures enhanced the peak in-cylinder pressure owing to improved flame speed and flammability limits. Adopting lean-burn operation and high compression ratio can efficiently improve combustion attributes in an
Devunuri, SureshPorpatham, Dr. E
Off-Highway Vehicles (OHVs) — including mining trucks, construction machinery, and agricultural equipment — contribute significantly to greenhouse gas (GHG) emissions and local air pollutants due to their dependence on fossil diesel. Achieving sustainable development goals in off-highway sectors requires transitioning toward alternate fuels that can reduce CO₂, NOₓ, and particulate matter (PM) emissions while maintaining performance and reliability. This paper comprehensively evaluates alternate fuels such as biodiesel, renewable diesel, compressed and liquefied natural gas (CNG/LNG), liquefied petroleum gas (LPG), hydrogen, and alcohol-based blends. Using insights from Service Bulletins, fuel standards, and the Worldwide Fuel Charter, it discusses fuel properties, engine compatibility, operational challenges, sustainability impacts, economic feasibility, safety considerations, and regulatory aspects. Case studies of alternate fuel deployment in OHVs illustrate practical challenges and
Mulla, TosifThakur, AnilTripathi, Ashish
Environmental concerns are prompting the global mobility sector to transition towards electrification. Increased research and development in the field of electric vehicles have made them an increasingly efficient and compelling option for reducing greenhouse gas emissions and improving the sustainability of freight transport. Electric vehicles require batteries that offer long range, shorter charging times and high energy efficiency. During long-distance travel, for customer convenience, mobile charging stations have become a trending and highly meaningful solution. For such mobile charging stations, it is essential to ensure the durability and safety parameters of the battery and its structure. For this to happen, it is mandatory that the system possess the strength and stiffness behavior to withstand the various dynamic loads arising from the environment and acting on the vehicle and system. Moreover, the system should maintain a weight that is as low as possible so that it is both
Sonare, PushpeshGaneshan, SubramanianDattawade, Vishal
The push for reducing greenhouse gas emissions has extended to various sectors, including outdoor power equipment. While electrification is a promising solution for low-power gardening tools, the substitution of small two-stroke engines becomes critical for applications requiring higher power and range. Biofuels and e-fuels produced from renewable sources present a viable short-term alternative, leveraging existing engine technologies to minimize dependence on fossil fuels. However, the ability of current engines to operate with these fuels while maintaining performance and emission levels without modifications requires thorough evaluation. This study investigates the feasibility of using e-fuels as sustainable alternatives to gasoline in small two-stroke engines. Preliminary computational fluid dynamics (CFD) simulations were conducted to evaluate the performance of the e-fuel after defining a proper fuel surrogate. Experimental tests were then carried out to assess combustion
Breda, SebastianoFontanesi, StefanoMerolla, SantoGagliardi, VincenzoCicalese, GiuseppePati, MatteoDalseno, LucaKuschel, Mario
Global efforts to mitigate climate change include ambitious long-term strategies by countries to achieve net-zero greenhouse gas emissions by 2050. The automotive sector is exploring carbon-free powertrains, with hydrogen emerging as a key technology. Its zero-emission potential positions it for widespread adoption in power generation, transportation, and industry. Hydrogen engines, particularly direct injection engines offering high power and efficiency, are gaining traction due to their adaptability using existing engine components. However, in a hydrogen direct injection engine, achieving proper mixing of hydrogen and air in the cylinder is challenging, making in-cylinder mixture formation a crucial factor for ensuring stable combustion. To predict hydrogen mixture formation in the cylinder, we conducted a Schlieren visualization experiment of the hydrogen jet. Based on the results, a detailed hydrogen jet model for the direct injection injector was developed. This model was then
Hisano, AtsushiSaitou, MasahitoSakurai, YotaIchi, Satoaki
There is growing demand for energy utilization due to stricter environmental emission norms to reduce greenhouse gases and other threats posed due to the emissions are major motivation factors for researchers to adopt on strategic plans to decrease the usage of energy and reduce the carbon contents of fuels, the usage of hydrogen or blend of hydrogen with CNG as a fuel in internal combustion engines is the best option. As hydrogen has lower volumetric energy density and higher combustion temperature, pure hydrogen-fueled engines produce lower power output and much higher NOx emissions than gasoline-fueled engine at stoichiometric air-fuel ratio. Blending of hydrogen with CNG provides a blended gas termed as hydrogen-enriched natural gas (hCNG). hCNG stands for hydrogen enriched compressed natural gas and it combines the advantages of both hydrogen and methane. The addition of Hydrogen to CNG has potential to even lower the CNG emissions and is the first step towards promotion of a
Syed, KaleemuddinChaudhari, SandipKhairnar, GirishSajjan lng, Suresh
This paper focuses on the potential application of hydrogen fueled internal combustion engine (HICE) in the off-road market, examining HICE based on a diesel engine. In the transition to HICE, priority was given to compatibility with existing systems, minimizing changes from the base engine. By adopting a PFI (Port Fuel Injection) method for fuel injection, low-pressure hydrogen supply was achieved. To address the issue of backfire associated with PFI, optimization of injection pressure using a variable pressure control valve, along with adjustments to valve timing and injection timing, was implemented to suppress backflow of residual gases into the intake system and minimize hydrogen retention. Regarding pre-ignition, in addition to suppressing hotspots, the relationship between the homogenization of the air-fuel mixture and NOx emissions was examined, revealing a correlation. This engine was mounted on a generator, and efforts were made to improve the important characteristic of
Shiraishi, KentaroKishi, ShinjiKato, DaichiMitamura, KentaMurakami, KeiMikuni, Yusuke
Recent climate changes, driven by greenhouse gas emissions, along with global regulations aimed at mitigating these effects, have intensified research on carbon-free fuels. Among these, hydrogen stands out as one of the most promising options. In this study, use is made of a recent 1D kernel expansion model developed by the authors, which is based on the conservation equations of mass, energy and deficient reactant. The theory of transient thermo-diffusion is also adopted to estimate the reactant and temperature gradients at the outer flame surface. The kernel expansion model accounts for the variability of thermodynamic properties both inside and outside the flame volume, including high-temperature ionization and dissociation effects. The kernel expansion model is used until the non-linear stretch effects are sufficiently relaxed. Subsequently, the propagation of the premixed flame is described by means of a two-zone combustion model. During both phases, the effects of hydrodynamic
Pretto, MarcoBozza, FabioGiannattasio, PietroDe Bellis, VincenzoUgliano, Emanuele
To mitigate greenhouse emissions such as carbon monoxide (CO), carbon dioxides (CO2), oxide of nitrogen (NOx) and particulate matter reduction Government of India implemented Bharat Stage VI (BS-VI) norms from year 2020. Moving to more stringent emission norms poses challenges for automakers in several ways such as meeting exhaust emissions, on board diagnostic, drivers’ inducement, and particulate filter monitoring on vehicle. It is imperative to upgrade engine management system for on-board diagnostics (OBD) that refers to a vehicles self-diagnostic and reporting ability. On board diagnostics systems enables owner of vehicle to gain access of the various vehicle sub-systems. OBD-II standards were made more rigid, requiring the malfunction indicator lamp (MIL) to be activated if emission-related components fail. Also, vehicle emissions carbon monoxide (CO), oxide of nitrogen (NOx) and particulate matter not to exceed OBD thresholds. Consequently, the use of specific oxide of nitrogen
Jagtap, PranjalSyed, KaleemuddinChaudhari, SandipKhairnar, GirishBhoite, VikramReddy, Kameswar
In response to the stringent CO2 regulations set to be enforced in Europe in 2030, there is a global demand for innovative technologies to significantly reduce CO2 emissions from internal combustion engines used in trucks, ships, and other applications. For this reason, future power sources are anticipated to adopt a three-pronged approach: electrification; hydrogen fuel used in fuel cells or internal combustion engines; and synthetic fuels (e-fuels) produced from renewable energy-sourced hydrogen, as approved by the European Commission (EC), and from raw materials that capture CO₂ directly from the atmosphere via the Direct Air Capture (DAC) method, combined with internal combustion engines. In this study, we aimed to absorb and capture “Green” CO₂ emissions from e-fuel and carbon-neutral (CN) fuels combined with internal combustion engines by investigating a method that atomizes a CO₂-absorbing solution. This approach involved spraying the solution and impingement the droplets within
Nohara, TetsuoNara, ShotaroKawamoto, YukiFukushima, NaoyaOchiai, Masayuki
The increasing demand for alternative fuels due to environmental concerns has sparked interest in biodiesel as a viable substitute for conventional diesel. Most automotive engines use diesel fuel engines. They contribute a major portion of today’s air pollution, which causes serious health issues including chronic bronchitis, respiratory tract infections, heart diseases, and many more. Greenhouse gases are produced using fossil fuel in the engines and causes global warming. To combat air pollution, we need clean renewable and environmentally friendly fuels. Due to depletion of fossil fuels, it has become necessary to find alternative fuel which are safer for the environment and humankind. One such possible solution is Biodiesel. In present study, series of experiments were carried out on 435cc naturally aspirate DI Diesel engine with port water injection and different blend of Jatropha based Biodiesel. Biodiesel was derived from Jatropha oil, produced using a heterogeneous catalyst
Bhoite, VikramSyed, KaleemuddinChaudhari, SandipKhairnar, GirishJagtap, PranjalReddy, Kameswar
Electricity is a fundamental necessity for individuals worldwide, serving as a force driving technological progress hitherto unimaginable. Electricity generation uses diverse methodologies based on available natural resources in a given geographic region. Conventional methods like thermal power from coal and natural gas, water-based hydropower, solar power from the sun, wind power, and nuclear power are used extensively, the former two being the dominant sources. The generation of nearly 70% of the world's electricity is estimated to be from thermal power plants; however, these operations lead to widespread environmental destruction, greenhouse emissions, and the occurrence of acid rain. Conventional thermal power plants run on the Rankine cycle principle of a boiler, a turbine, a condenser, and a pump. A similar method may be used in the Organic Rankine Cycle (ORC) with the use of solar energy, where heat is transferred to the working fluid in the boiler using a heat pipe, a passive
Deepan Kumar, SadhasivamKumar, VDhayaneethi, SivajiMahendran, MSaminathan, SathiskumarR, KarthickA, Vikasraj
Zero emission vehicles are essential for achieving sustainable and clean transportation. Hybrid vehicles such as Fuel Cell Electric Vehicles (FCEVs) use multiple energy sources like batteries and fuel cell stacks to offer extended driving range without emitting greenhouse gases. Optimal performance and extended life of the important components like the high voltage battery and fuel-cell stack go a long way in achieving cost benefits as well as environmental safety. For this, energy management in FCEVs, particularly thermal management, is crucial for maintaining the temperature of these components within their specified range. The fuel cell stack generates a significant amount of waste heat, which needs to be dissipated to maintain optimal performance and prevent degradation, whereas the battery system needs to be operated within an optimal temperature range for its better performance and longevity. Overheating of batteries can lead to reduced efficiency and potential safety hazards
BHOWMICK, SAIKATChuri, Chetana
TOC
Tobolski, Sue
Recent policies have set ambitious goals for reducing greenhouse gas (GHG) emissions to mitigate climate change and achieve climate neutrality by 2050. In this context, the feasibility of hydrogen applications is under investigation in various sectors and promoted by government funding. The transport sector is one of the most investigated sectors in terms of emission mitigation strategies, as it contributes to about one-fifth of the total GHG emissions. This study proposes an integrated numerical approach, using a simulation framework, to analyze potential powertrain alternatives in the road transport sector. Non-causal point parametric vehicle models have been developed for various vehicle classes to evaluate key environmental, energy, and economic performance indicators. The modular architecture of the simulation framework allows the analysis of different vehicle classes. The developed framework has been used to compare powertrain alternatives based on hydrogen and electricity energy
Pipicelli, MicheleSedarsky, DavidDi Blasio, Gabriele
Recent experimental work from the authors’ laboratory demonstrated that applying a boosted current ignition strategy under intensified flow conditions can significantly reduce combustion duration in a rapid compression machine (RCM). However, that study relied on spark anemometry, which provided only localized flow speed estimates and lacked full spatial resolution of velocity and turbulence near the spark gap. Additionally, the influence of turbulence on combustion behavior and performance across varying flow speeds and excess air ratios using a conventional transistor-controlled ignition (TCI) system was not thoroughly analyzed. In this study, non-reactive CFD simulations were used to estimate local flow and turbulent velocities near the spark gap for piston speeds ranging from 1.2 to 9.7 m/s. Simulated local velocities ranged from 0.7 to 96 m/s and were used to interpret experimentally observed combustion behavior under three excess air ratios (λ = 1.0, 1.4, and 1.6). Combustion was
Haider, Muhammad.ShaheerJin, LongYu, XiaoReader, GrahamZheng, Ming
Due to strengthened CO2 regulations, the automotive industry is facing the challenge of reducing greenhouse gas emissions. In response, the industry has focused on developing various technologies that enhance fuel economy and reduce greenhouse gas emissions. Hybrid electric powertrains have demonstrated significant potential to improve fuel economy and reduce greenhouse gas emissions. The improvements resulting from hybrid electric powertrains depend on the degree of electrification, which is closely related to the sizing of the motor and battery. However, hybridization increases the complexity of the powertrain. As multiple power sources are involved, complex control algorithms must be developed to allocate power usage among various driving scenarios while fulfilling driver requests. One way to simplify hybrid power management control is to implement optimization strategies that determine the operating states for each component during different driving scenarios, aiming to minimize
Echeverri Marquez, ManuelBhoge, MaheshLago, RafaelEngineer, NayanBhadra, KaustavWhitney, ChristopherBaur, Andrew
The objective of this trial was to compare the energy efficiency and performance of battery electric and conventional diesel tractors. Controlled road tests replicating normal operations were conducted using two electric and two diesel day-cab tractors. The test protocol was based on the TMC - Type III RP 1103A and SAE J1526 test procedures. The tests were conducted on a 110 km long route that included a 59 km hilly portion with a maximum altitude difference of 307 m. The tractors were divided into test groups of two vehicles. Trailers and drivers were switched throughout the trial between the tractors in a test group. The tests found that the two electric trucks consumed 60% and 63% less energy than their counterpart diesel trucks, respectively. Considering the average emission factor for production of electricity in Canada, the electric trucks emitted on average 82% less GHG emissions than the conventional diesel-powered tractors. The two diesel trucks showed similar fuel consumption
Surcel, Marius-DorinPartington, MarkTanguay-Laflèche, MaximeSchumacher, Richard
The heavy-duty transportation sector is a major contributor to greenhouse gas emissions, highlighting the urgent need for zero-emission solutions. This research develops a multilevel control architecture that optimizes fuel economy and minimizes emissions in fuel cell hybrid heavy-duty vehicles, equipped with proton exchange membrane fuel cell and battery pack as main power sources. The detailed fuel cell system model incorporates reactants and thermal dynamics, including air supply, hydrogen flow, water management and their effects on reaction kinetics, membrane conductivity, water balance, performance and durability. The low-level control strategy is designed using a physics-based approach that accounts for critical constraints, including temperature, membrane water content and differential pressure between the cathode and anode. By identifying optimal setpoints for key control variables, this methodology enables the development of accurate control maps for actuator management
Bove, GiovanniAliberti, PaoloSimone, ChristianSorrentino, MarcoPianese, Cesare
Recent studies highlight the urgent need to reduce greenhouse gas (GHG) emissions to mitigate the impacts of global warming and climate change. As a major contributor, the transport sector plays a vital role in these efforts. Ethanol emerges as a promising fuel for decarbonising hard-to-electrify propulsion sectors, thanks to its sustainable production pathways and favourable physical and combustion properties, such as energy density, rapid burning velocity, and high knock resistance. This work proposes a methodology to enable the possibility of replicating the combustion behaviour of ethanol in a 1D CFD simulation environment representative of a single-cylinder research engine. Spark-ignition combustion is simulated through the Eddy Burn-Up combustion model previously calibrated for standard fossil gasoline. The combustion model features a laminar flame speed neural network, trained and tested through reference chemical kinetics simulations. The combustion model showed great accuracy
Ferrari, LorenzoSammito, GiuseppeFischer, MarcusCavina, Nicolò
Reducing greenhouse gas (GHG) emissions in the transportation sector is a significant challenge. A multi-technology approach is the most practical and sustainable solution for minimizing the environmental impact of road transport. Alternative gaseous fuels derivable from bio sources have the potential to significantly cut equivalent carbon dioxide (CO2eq) emissions from a Well-to-Wheel (WtW) perspective, and the development of technologies that allow to improve the efficiency of natural gas-powered Heavy Duty (HD) Spark Ignition (SI) engines is of strategic importance. In such applications, charge dilution strategies might have the potential to increase engine efficiency at a relatively low implementation cost. Diluting the in-cylinder charge can reduce fuel consumption by decreasing wall and pumping losses, and increasing the Heat Capacity Ratio (γ). The coupling with innovative technologies aimed at enhancing ignition energy, influencing combustion development, could be a promising
Di Domenico, DavideNapolitano, PierpaoloPapi, StefanoRicci, FedericoGolini, StefanoRapetto, NicolaGiordana, SergioBeatrice, Carlo
The maritime industry is among the most energy-intensive sectors, and achieving fleet decarbonization is crucial to significantly reduce greenhouse gas emissions. As a transitional fuel, natural gas (NG) presents a viable short-to-midterm solution. Compared to conventional marine fuels, NG has the potential to lower carbon dioxide emissions by approximately 20–30%. However, to fully leverage this potential on carbon footprint reduction, substantial advancements in combustion technologies are required. One promising approach to enhance the efficiency of SI NG engines is the implementation of Passive Pre-Chamber (PPC) technology. This strategy enables leaner combustion, improving thermal efficiency, mitigating the occurrence of knocking, and reducing NOx emissions. This study presents both experimental and numerical investigations to analyze the impact of charge dilution and ignition timing on the performance and emissions of a single-cylinder prototype NG PPC SI engine for marine
Marchitto, LucaPesce, FrancescoAccurso, FrancescoTornatore, CinziaGorietti, ValentinaBuzzi, LucaGrosso, AlessandroLuci, MatteoNapolitano, PierpaoloPennino, VincenzoBeatrice, CARLODi Domenico, DavideGiardino, Angelo
All mobility sectors are facing the challenge to contribute actively to the reduction of environmental pollution and of the impact on climate change driven by Greenhouse Gas effect. One of the most active sectors in the research of environment-friendly propulsion propositions is the recreational and light-commercial boating. Presently, many of the boats operating in this sector are propelled by internal combustion engines derived from road applications. In this work, the effects of replacing conventional fossil-derived B7 diesel with Hydrotreated Vegetable Oil (HVO) were experimentally investigated in a modern Medium-Duty Engine, using the advanced biofuel initially as drop-in replacement, and then repeating the testing after the recalibration of the engine combustion set points. Comparing the results of the replacement of diesel with HVO showed appreciable benefits in terms of NOx, Particulate Matter (PM), mass fuel consumption and Well-to-Wake (WtW) CO2 thanks to the inner properties
Cosseddu, CinziaSpedicato, TonioPennazio, DavideVassallo, AlbertoFittavolini, Corrado
The reduction of the overall greenhouse gas and pollutant emissions from ground vehicles is mandatory to fight against global warming and health issues. Moreover, regarding the increasing demand related to the population growth, the energy requirement for mobility may significantly increase during coming years. Meeting greenhouse gas emission targets is not only about commitment to regulations but also fundamentally about enhancing human well-being. Consequently, the diversification of low-carbon energy sources is of huge interest. The use of Hydrogen (H2) as a sustainable energy source in ground transportation is an alternative or a complementary solution to the full electric vehicles. Hydrogen for mobility can be used in two types of energy converters: The Proton-Exchange Membrane Fuel Cell or the H2 adapted Internal Combustion Engine (H2-ICE). This last has the advantage of its strong maturity with the reuse of existing production infrastructures from conventional ICE and low raw
Laget, OlivierBardi, MicheleQuintens, HugoGiuffrida, VincentBramoullé, ClémentSikic, Ivan
This study presents a CFD-based evaluation of ignition strategies for enabling ammonia combustion in a light-duty internal combustion engine. The model was first validated against experimental data for both pure ammonia spark ignition and dual-fuel ammonia-diesel compression ignition cases. Upon validation, three ignition strategies were investigated: dual-fuel compression ignition with sixty percent ammonia energy fraction, and multi-spark and passive pre-chamber ignition under stoichiometric conditions. Simulations were used to assess combustion phasing, efficiency, and emissions characteristics. The dual-fuel mode enabled stable ignition but resulted in incomplete combustion, with three-dimensional contours revealing that central regions of the chamber remained largely unburned, contributing to high ammonia slip and highlighting the need for further optimization of spray targeting and combustion chamber design. The multi-spark strategy achieved the highest efficiency through rapid
Shafiq, OmarMenaca, RafaelLiu, XinleiUddeen, KalimTang, QinglongTurner, JamesIm, Hong G.
Hydrogen as fuel in internal combustion engines is a promising solution for reducing greenhouse gas emissions, as its combustion produces only water vapor. One potential application is in dual fuel (DF) engines, where diesel is used to ignite the mixture, and hydrogen serves as the primary fuel. However, there is limited literature on the use of hydrogen in compression ignition (CI) engines for off-road applications running in dual fuel diesel/hydrogen, which motivates this study. The focus is on a 3-cylinder, 1-liter naturally aspirated (NA) engine with a compression ratio of 17.5:1 equipped with direct injection (DI) for diesel. Retrofitting the engine with 3 port fuel injectors, it was possible to feed the engine with hydrogen by the control system elaborated in the laboratory. The study aims to analyze dual fuel diesel/hydrogen combustion characteristics and the emissions across different engine speeds (from 1600 rpm to 3600 rpm) and loads (30%, 50% and 70%). The dual fuel
Gelé, RaphaëlMancaruso, EzioRossetti, SalvatoreRousselle, ChristineBrequigny, Pierre
To curb global warming and meet stricter greenhouse gas emission standards all over the globe, it is essential to minimize the carbon footprint of applications in the mobility and transport segment. The demands on mobility, transportation and services are constantly increasing in line with worldwide population growth and the corresponding need for economic prosperity. This ongoing trend will lead to a significant increase in energy requirements for mobility-related applications in the upcoming time, despite all efficiency improvements. The timely introduction and accelerated spread of low-carbon/carbon-neutral energy sources is therefore of crucial importance. In addition to the switch to electric propulsion systems, particularly in the light-duty vehicle sector, the use of advanced and optimized hydrogen (H2)-powered internal combustion engines (ICE) represents a parallel, compatible technical option, as these applications will also meet the most stringent requirements in terms of
Koerfer, ThomasZimmer, PascalLi, ZhenglingPischinger, StefanLückerath, Moritz
In the context of greenhouse gas emissions (GHG) reduction the most viable short-term solution in the maritime sector is the use of renewable carbon-free fuels. Among these, ammonia represents a possible alternative in compression ignition (CI) engines operating in dual fuel (DF) mode. Although, such fuel features low chemical reactivity, especially in lean mixtures, resulting in poor combustion efficiency, exhaust ammonia slip and low engine performance, DF combustion can be an interesting strategy to overcome such limitations. In this work a wide numerical examination of diesel injection strategies is presented, while ammonia acts as the primary fuel with energy supply around 80%. Since the original marine engine, fuelled with natural gas (NG), presents a single diesel injection, firstly, a pilot injection is added and different diesel mass shares between pilot and main are investigated, by varying the injection rate shape and the pilot start of injection (SOI). Calculations are
Cameretti, Maria CristinaDe Robbio, RobertaPalomba, Marco
The need for greenhouse gas emission reductions leads to decreasing emission limits in road traffic. The development of efficient powertrains and the use of renewable energy sources are crucial in order to meet these targets. Electrification is one of the key technologies that can help to achieve higher efficiency and lower emissions. Besides the passenger car segment, electrification has started to play a more important role in heavy-duty applications as well. One technology that has been discussed in the last years is the electrification of heavy-duty semi-trailers. In the joint research project "evTrailer2" funded by the German Federal Ministry for Economic Affairs and Climate Action, the potential of different technologies for electrified semi-trailer systems in long-haul applications is evaluated. The overall project goal is the development of high-efficiency technologies to help reduce the fuel consumption and therefore the greenhouse gas impact of large semi-trailer trucks. The
Knaup, LarsBeidl, Christian
Ammonia (NH3) use as fuel poses technical challenges such as increased nitrogen-based and unburned NH3 emissions. This study used a 0D model coupled with detailed NH3 kinetics to evaluate the effect of equivalence ratio (ϕ) from 0.7 to 1.0 in a heavy-duty compression ignition engine converted to spark ignition operation. The goal was to evaluate how ϕ affected NOx and N2O formation and/or destruction at constant fuel energy per cycle, engine speed, and CA50. Simulated NOx emissions (i.e., NO + NO2) followed a trend similar to the one typically observed for hydrocarbon fuels in a SI engine, but that was different from the experiment. In addition, it underpredicted NOx emissions for ϕ = 0.7 by 79% and overpredicted NOx emissions for ϕ = 1 by 576%. The simulation showed that thermal NO production was more than 80% from the total NO production, but the effect of ϕ on this percentage was negligible. Then, predicted N2O emissions had an opposite trend and were three orders of magnitude lower
Saenz Prado, StefanyAlvarez, Luis F.Trujillo Grisales, Juan M.Akkerman, VyacheslavDumitrescu, Cosmin E.
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
Donateo, TeresaMujahid, TalhaMorrone, PietropaoloAlgieri, Angelo
Alcohol-to-jet (ATJ) upcycling of ethanol to sustainable aviation fuel (SAF) is an attractive emerging pathway for SAF production, especially in the US Midwest with large-scale corn ethanol production. Only 39% of the corn carbon is converted to ethanol, 20% is emitted as CO2. Capturing the CO2 to produce additional ethanol or SAF directly can increase the carbon yield. To guide technology selection, this work used life cycle assessment for several CO2-to-SAF production pathways. Additionally, improvements for corn ethanol production were explored by replacing natural gas burners with heat pumps for corn drying, which reduced the carbon intensity of corn ethanol by nearly 16%. But subsequent upgrading of the ethanol to SAF is only 4.5–20% better than conventional aviation fuel. By contrast, CO2-based alternative routes to SAF fared better, reducing carbon intensities between 83% and 90%. Gas fermentation of CO2 to ethanol with subsequent ATJ upcycling to SAF was contrasted to Fischer
McCord, StephenTalsma, SamBouchard, JesseyZavaleta, Victor GordilloHe, XinSick, Volker
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