Browse Topic: Hybrid engines

Items (149)
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
Methanol obtained from regenerative sources is a renewable fuel with many advantages when used in a spark ignition combustion process. Methanol has a comparatively high enthalpy of vaporization, leading to lower combustion temperatures (compared to gasoline combustion) and, hence, lower wall heat losses as well as a reduced tendency to autoignition. Several cold start methods were examined for this paper. In a serial hybrid powertrain with one internal combustion engine, ICE, and one electric machine, the load demand of the ICE can be controlled for best efficiency. The ICE is operated on liquid renewable fuel, which provides a high volumetric and gravimetric power density, easy energy storage, delivered from a very cost effective already existing infrastructure of fuel distribution. The electric machine provides comfortable electric driving, high efficiency, locally and temporary zero emissions. The eFuel should be produced from a closed carbon cycle. Methanol is a challenging fuel
Dobberkau, MaximilianWerner, RonnyAtzler, Frank
Achieving zero emissions across transportation is a tremendous challenge. The upcoming Euro 7/VII standards, set to be enforced in 2025, will mandate further reduction in ICEs exhaust emissions. Thus, additional improvements and potential new technologies and fuels are needed to design ultra-low emissions vehicles. Hydrogen seems to be a very attractive fuel, thanks to its high lower heating value, clean combustion, and extremely low pollutant emissions, due to the zero-carbon content. Nevertheless, NOx emissions are still an issue in hydrogen fueled engines and optimized lean-burn combustion and suitable after-treatment NOx reduction are mandatory to reach high specific power and efficiency and near zero NOx emissions, thus enabling H2-ICE powered vehicles to be zero-impact emitting technology solution. Selective Catalytic Reduction by using NH3 as the reducing agent is the most effective control technology for NOx abatement. Nevertheless, ongoing research and innovation are critical
Crispi, Maria RosariaConde Cortabitarte, CarlaOcchicone, AlessioPiqueras, PedroArsie, IvanPianese, Cesare
Eco-sustainability is one of the main aspects focused on motor industries, including those related to air transport, which work to realize alternative propulsion systems, such as Hybrid Electric Propulsion Systems, for reducing CO2 emissions. Despite the minor CO2 emission produced by Hybrid Electric Propulsion Systems, these categories of propulsors require a proper control architecture for managing combustion and electric energies based on driver decisions and the flight mission set. A supervisory control logic, based on a Nonlinear Model Predictive Control (NMPC), is presented in this work to guarantee a specific State of Charge level of batteries coupled with the minimization of fuel consumption of an aeronautical Hybrid Propulsion System. These two goals are achieved by the designed NMPC, which provides the best amount of torque between the propulsors belonging to the analysed aeronautical powertrain, consisting of an Internal Combustion Engine and an Electric Machine. The
Tordela, CiroFornaro, Enrico
Light-duty vehicles (LDV) are scaling up electrification technologies from battery to dedicated hybrid engines (DHEs). The success from electrification of LDVs can be a starting point to look into a similar trending development of commercial vehicles (CV), which are bigger and heavier with more demanding work cycles. “Greenhouse Gas Emissions Standards for Heavy-Duty Vehicles (HDV)—Phase 3” establishes new CO2 emission standards for MY 2032 (Model Year) and later HD vehicles with more stringent CO2 standards phasing in as early as MY 2027 for certain vehicle categories. In this article, the focus is about improving the operational efficiency of MDHD (medium-duty and heavy-duty) vehicles through a selected electrification technology in this study rather than pure BET (battery electric truck). Extended-range electric vehicle (EREVs) systems are studied here to address sustainability regarding charging infrastructure and by using the renewable fuels (hydrogen, ammonia, methanol, and
Wang, HailongMa, TiancaiShuai, ShijinWang, ZihuiSong, Xubin
High Pressure Sensors (HPS) are essential for internal combustion engines and hybrid engine systems. High pressure sensor measures the pressure in the Delivery fuel rail Pipe Module (DPM) to allow the Engine Control Unit (ECU) to control the high pressure pump to generate the required fuel pressure. Most high pressure sensors measure the displacement of the metal-diaphragm according to pressure, and are mainly composed of Half-bridge type Micro Electro Mechanical System (MEMS) elements of the piezo-resistive method. This time, we would like to introduce a high pressure sensor that uses a Full-bridge type MEMS structure. This is cheaper than the existing one and can provide higher performance with reliability. However, there are disadvantages of the full-bridge type applied to high pressure sensors. Unlike the Half-bridge method that measures displacement over a wide area, it measures displacement over a narrow area, so it has the disadvantage of weak to external noise due to increased
Lim, SeungGuLee, DongYoungKim, JungTaekShin, MoonSung
Heavy-duty trucks idling during the hotel period consume millions of gallons of diesel/fuel a year, negatively impacting the economy and environment. To avoid engine idling during the hotel period, the heating, ventilation, and air-conditioning (HVAC) and auxiliary loads are supplied by a 48 V onboard battery pack. The onboard battery pack is charged during the drive phase of a composite drive cycle, which comprises both drive and hotel phases, using the transmission-mounted electric machine (EM) and battery system. This is accomplished by recapturing energy from the wheels and supplementing it with energy from the engine when wheel energy alone is insufficient to achieve the desired battery state of charge (SOC). This onboard battery pack is charged using the transmission-mounted EM and battery system during the drive phase of a composite drive cycle (i.e., drive phase and hotel phase). This is achieved by recapturing wheel energy and energy from the engine when the wheel energy is
Huang, YingHanif, AtharAhmed, Qadeer
One 1.5L Miller-cycle turbocharged four cylinder gasoline hybrid engine is installed on a certain hybrid vehicle. When accelerating at low to medium speeds with a small throttle, there is a "da da" knocking noise inside the car, which seriously affects the overall sound quality of the vehicle. By analyzing the vibration and noise data of the engine, it was found that the frequency of the abnormal knocking sound is 200-2000Hz, which presents a half order characteristic in the time domain, that is, one knocking occurs when the engine crankshaft rotates twice. Through Hilbert demodulation analysis of the vibration data in the problem frequency range, it was found that the knocking noise was modulated in the frequency domain, with a modulation frequency of half of the crankshaft rotation frequency. By building a fully flexible multi-body dynamic model of a hybrid powertrain and inputting the engine's cylinder pressure excitation, the combustion excitation is coupled with mechanical
Dan, Kong
The authors have witnessed a notable surge in the number of designs and in the guidance material for electric and hybrid aircraft. FAA and EASA have continued to evaluate the safety of Propulsion Battery Systems (PBS), with a focus on thermal runaway containment testing. As a result, a harmonization white paper [7] was issued to provide a certification path for Thermal Runaway (TR) Hazards, followed by an EASA certification memorandum on the acceptable approaches for the certification of Electric/Hybrid Propulsion Systems (EHPS). Recently, an FAA Advisory Circular (draft) was issued for the “powered-lift” aircraft that feature these propulsion battery systems. Despite the advances made by electric/hybrid aircraft manufacturers and the aviation authorities, there is still a missing piece of the puzzle. Mainly, engineering work still needs to be done to properly integrate the EHPS architecture to achieve safety objectives. The burden is still on systems engineering to propose their own
Hanna, MichaelWalker, Cherizar
China 6b regulation was fully implemented since July 2023 with very strict emission standards for HC, NMHC, NOx, and CO. The country is now also in the process of developing China 7 regulation, which will perhaps impose even stricter emission limits and extra criteria pollutants including NH3. Moreover, increasingly strict fuel consumption regulation has been implemented as well and it is highly possible that greenhouse gas emission limits will be included in the China 7 regulation. With the hybrid technology innovation, PHEVs are effective in fuel economy and emission reduction, which are favored by manufacturers and consumers, and leading to a rapid increase in market share. Through the optimization of hybrid architecture and the synergy of electric motors, the operating conditions of the hybrid engine have been optimized, making it more stable and avoiding extreme engine operating conditions compared to traditional ICE, which also provides possibilities for optimizing the after
Wang, JimingLi, ChunboFeng, XiangyuChen, XiaolangBoger, ThorstenTian, LichenHu, XianliZeng, JunTian, TianGao, BojunLi, DachengLiu, ShichengJiang, Fajun
With the global promotion of carbon neutrality policies, internal combustion engine (ICE) of traditional fossil fuel is gradually transitioning to carbon neutral fuel ICE, and hybrid dedicated engines are gradually replacing traditional internal combustion engines in the passenger car market. Ultra-lean combustion supported by active pre-chamber is one of the key technologies for achieving high thermal efficient over 45% BTE. However, there are still issues like cold start and PN emissions caused by impingement of liquid fuel injection in pre-chamber, and there is still room for improvement in thermal efficiency by less energy of pilot ignition fuel. Gaseous fuel such as hydrogen or methane have no wetting issues, and can be more easily controlled in terms of the injection amount in pre-chamber, thereby using a less amount of gaseous fuel as the pilot ignition fuel could be a solution. Due to the above situation, this article conducted experiments on a lean burn gasoline engine by
Liu, YaodongLiu, MingliHe, ZhentaoLi, XianZhao, ChuanQian, DingchaoQu, HanshiLi, Jincheng
As regulations regarding vehicle emissions and fuel consumption become increasingly stringent, the development of hybrid power systems is accelerating, primarily due to their benefits in fuel efficiency and reduction of pollutants. Hybrid engines are specially designed to operate optimally at mid to high speeds and loads. But for low-speed low-load conditions, due to the relatively low in-cylinder tumble intensity and lower injection pressure, the fuel-air mixture tends to deteriorate, resulting in an increase in particle number. To enable the engine to reach optimal RPM and load quickly during frequent start-stop cycles, hybrid engines typically set a higher startup engine speed and establish fuel rail pressure more quickly compared to traditional engines. Yet hybrid engines still encounter challenges of soot generation during cold start conditions. Especially in urban driving conditions where the hybrid engine frequently experiences startups and idling, the soot generation problem
Liu, ChangyeMan, XingjiaCui, MingliLiang, YuanfeiWang, ShangningLi, Xuesong
Front End Accessory Drive (FEAD) systems are used in automobiles to transfer power from the engine-to-engine accessory components such as the alternator, water pump, etc. using a Belt and Tensioner. The emergence of Mild hybrid technologies has led to the replacement of alternator with Belt-driven Integrated Starter-generator (B-ISG). In conventional configuration of FEAD, the power transfer is in single direction but in mild hybrid engine power transfer is bidirectional: tight and slack side of the Belt changes as per Torque assist or Regeneration mode. The presence of an integrated starter-generator (ISG) in a belt transmission places excessive strain on the FEAD System and necessitates checking the dynamic performance of FEAD System thoroughly. Study of Increase in Engine Torque in existing Vehicle was done to understand its effect on various system. This vehicle is Mild Hybrid and consists of Belt-driven Integrated Starter generator system. Increase in Engine torque lead to
Kumar, AdityaGupta, AvinashBharti, Anil Kant
The hybrid engines produced by most original equipment manufacturers (OEMs) have been modified to fit within the framework of conventional engine designs. Recently, Geely has introduced a new 1.5-liter (1.5L) inline four-cylinder (I4) TGDI engine, specifically designed to meet the requirements of its innovative, efficient, and intelligent hybrid powertrain architecture. This engine achieves an impressive brake thermal efficiency (BTE) of 44%, as well as high specific torque at 153 Nm/L and high specific power at 67 kW/L. To attain this superior performance, the following technical strategies were implemented: a high compression ratio, the robust Miller cycle, an extended piston stroke-to-bore ratio, an intake port optimized for high tumble, cooled exhaust gas recirculation (EGR), and an advanced high-energy ignition system. Among these, the middle four strategies, in conjunction with piston cooling jets and enhanced exhaust-side cooling, all contribute to improved in-cylinder
Li, QiangLiu, YangZhang, PeiyiYan, PingtaoLi, HongzhouZhu, YunfengJi, YanLi, MingguiCui, Boyue
The high-efficiency dedicated hybrid engine (DHE) has led to increasingly complex challenges in engine thermal management. On one hand, the high compression ratio of up to 16:1 makes the engine more susceptible to knocking, necessitating meticulous thermal management to mitigate the potential sensitivity to metal temperature. On the other hand, extensive use of external cooled exhaust gas recirculation (EGR) helps reduce knocking and improve thermal efficiency, but it also raises temperature levels and requires additional cooling measures. For the 1.5L DHE developed by SAIC Motor, a split cooling structure was employed in the engine cooling system design, with the cylinder head water jacket and cylinder block water jacket arranged in parallel and equipped with different coolant outlets. By utilizing a dual thermostat to control flow, this design allows for adjustable flow distribution, providing effective cooling to the cylinder head while reducing cooling to the cylinder block. The
Xu, ZhengXia, QiWeiPeng, Chaowang, YanJun
Due to the global drive for carbon neutrality, passenger vehicle gasoline engines are transitioning to higher levels of electrification, such as hybrid electric vehicles and plug-in hybrid electric vehicles, HEVs and PHEVs. Compared with conventional internal combustion engine (ICE) vehicles, the HEV or PHEV engine whilst in ICE only operation, typically operates for multiple shorter periods, in turn the engine coolant and lubricant temperatures are lower. Conventional internal combustion engines are often able to yield valuable fuel economy benefits by selecting appropriate engine lubricating oils, typically employing reduced viscosity and suitable additives. There are commercial engine tests available for measurement, often in an engine test cell for precision. Steady state testing is also a simplified option. Such efforts require care, as the accurate measurement is technically and practically challenging. This level of difficulty is again increased by the further complication of
Butcher, RichardBradley, NathanJamieson, MatthewChambers, Thomas
Turbulent jet ignition (TJI) combustion using pre-chamber ignition can accelerate the combustion speed in the cylinder and has garnered growing interest in recent years. However, it is complicated for the optimization of the pre-chamber structure and combustion system. This study investigated the effects of the pre-chamber structure and the intake ports on the combustion characteristics of a gasoline engine through CFD simulation. Spark ignition (SI) combustion simulation was also conducted for comparison. The results showed that the design of the pre-chamber that causes the jet flame colliding with walls severely worsen the combustion, increasing the knocking intendency, and decrease the thermal efficiency. Compared with SI combustion mode, the TJI combustion mode has the higher heat transfer loss and lower unburned loss. The well-optimized pre-chamber can accelerate the flame propagation with knock suppression. Strong-tumble flow distorts the jet flame propagation, which is not
Liu, ShangLin, ZhelongQi, YunliangLu, GuoxiangWang, BoLiu, YangWang, Zhi
In the pursuit of carbon emission reduction, hybridization has emerged as a significant trend in powertrain electrification. As a crucial aspect of hybrid powertrain system development, achieving high brake thermal efficiency (BTE) and a wide operating range with high efficiency are essential for hybrid engines to effectively integrate with the hybrid system. When developing dedicated hybrid engines (DHE), several design considerations come into play. First, in order to make efficient use of available resources and enable engine production on the same assembly line as conventional engines, it is crucial to maintain consistency in key design parameters of the cylinder head and block, thus extending the platform-based design approach. Among the key measures to achieve high BTE, cooled exhaust gas recirculation (EGR) has been extensively explored and proven effective in improving efficiency by mitigating knocking and reducing engine cooling heat loss. Fast combustion, acting as a
Xu, ZhengQiu, JieZhang, ZiQingCheng, ChuanhuiZhang, YaJunYang, YangWang, YingzhenLu, YuanZhou, ZhouLi, XiaoYang
Taking into account the high rotor speed of the generator and the trend of high voltage in direct current microgrids in high-power aviation hybrid propulsion systems, a hybrid power system with a power of 200 kilowatts (kW), a voltage of 540 volts (V), and a rated generator speed of 10500 r/min was established. Anticipating the demands of future high-power system tests, a matching simulation model was developed. The paper discusses various aspects including model construction, test design, and result validation, proposing an overall control strategy for series hybrid aviation propulsion systems – utilizing lithium-ion batteries to stabilize grid voltage and using the turboshaft-generator unit as the primary power source to meet the main power demands of the electric propulsion system. The established model consists of four modules: turboshaft engine, power generator, voltage-stabilizing battery, and electric motor/propeller. These modules are independently controlled and are unified
Diao, BoLi, PoZhu, JianfengHuang, GuochenShe, YunfengXing, Yaoren
The fuel economy and emission of the hybrid vehicle depend largely on the selected engine. And the dedicated hybrid engine (DHE) can be controlled to operate in the optimal operating range because DHE can be decoupled from the vehicle transmission system. The main purpose of this paper is to improve the thermal efficiency of the diesel engine under common operating conditions combined with high compression ratio (CR) and early or late intake valve closing (IVC) angle. According to the vehicle road spectrum data, the optimal operating range of the engine is determined to be 1200-1400 rpm and 70%-90% load. Then CR and IVC angle are optimized by using the calibrated one-dimensional thermodynamic model of the engine under limited peak combustion pressure (Pmax). The results show that the adjustment of IVC angle and CR can control the thermal state at the end of compression stroke. The combination of CR and IVC angle can achieve the optimal fuel consumption improvement. The minimum brake
Wang, XiaosaLin, ZhiqiangWang, HuHe, HuaWang, XiaohuiLiang, Depu
Hybrid vehicles, compared to pure fossil fuel vehicles, have added power battery pack, high-power electric motors. The space of the aftertreatment is limited, so the layout position of the aftertreatment system must be optimized. Meanwhile, the European 7 emission standard reduces the particulate number (PN) limit particles size from 23nm to 10nm, presenting new challenges for the aftertreatment system. The focus of this study is to investigate the variations in particles size distribution and nanostructure of soot particles during the exhaust along a dedicated hybrid engine aftertreatment system (catalyst carrier free). Four operating conditions were selected for the test, namely 2000 r/min-0.2 MPa, 2000 r/min-0.8 MPa, 4500 r/min-0.2 MPa, and 4500 r/min-0.8 MPa. The particles sampling points are before Three-way catalyst (TWC), after TWC, and after gasoline particulate filter (GPF). Engine Exhaust Particle Sizer (EEPS) was used to analyze the changes in particle modal distribution
Fu, JialeHu, ZhiyuanFang, LiangLou, DimingTan, PiqiangYin, Qi
With the increasing regulatory stringency on emission reduction and efficiency improvement, the automotive industry has experienced a significant shift in the hardware platform. Among technology candidates, hybrid technology is still considered one of the most viable approaches to meet the regulation requirement (both emission and efficiency) at an affordable cost to both the customer and the manufacturer. New engine operating characteristics are expected in hybrid applications which would potentially result in different performance requirements for the engine oil. Therefore, it is crucial to understand those characteristics of a hybrid powertrain, from which the insights of fluid requirements can be derived. A hybrid vehicle test study was conducted to evaluate the engine operation of different kinds of hybrid platforms. The hybrid operation has been well characterized by thoroughly analyzing parameters on each engine. The temperature profile from each hybrid powertrain was evaluated
Garelick, KennethShao, HuifangHidetaka, HoshinoLi, YanfeiShuai, Shijin
After three years away from the U.S. market with its range-topping SUV, the Land Cruiser, Toyota unveiled the redesigned 2024 Land Cruiser in Salt Lake City on Aug. 1. The model, long known around the world for its durability and offroad credentials, arrives with the SUV competition hotter than ever. The company said the new model will start at around $55,000. The new Land Cruiser has just one engine option, the i-Force Max turbo 2.4-L four-cylinder hybrid that generates 326 hp and 465 lb-ft (630 Nm) that is routed through an 8-speed automatic transmission. All models are equipped with what Toyota classifies as a “full-time four-wheel-drive system” with a lockable center differential and an electronically controlled 2-speed transfer case to impart high- and low-range capability. Also standard is a lockable rear differential to apportion power in a 50/50 ratio across the rear axle.
Clonts, Chris
Focusing on coastal or inland navigation cities, where emissions from ships are not negligible concerning global ones, the possibility of reducing exhaust gas pollution would have more benefits for public health and air quality. Therefore, in recent years, increasing attention on environmental sustainability is driving the shipbuilding industry towards greener propulsion based on full-electric or hybrid-electric propulsion systems. This work is presented a parallel hybrid system composed of two electric motors, one internal combustion engine, and lithium battery storage. All motors are coupled to the propeller through a specially designed transmission system based on the High Sliding Gear theory (HSG). The hybrid-electric propulsion system is designed to extender the battery pack durability, ensuring a smooth profile of the required current, through the complementary action of the batteries and the internal combustion engine. Then, the overall performance of the hybrid propulsion
Marialto, RenatoBrando, GianlucaDannier, AdolfoSementa, PaoloCardone, MassimoFornaro, Enrico
In the last decades, the requirement related to the reduction of energy waste has been focused on the aeronautical field for decreasing CO2 emissions in propulsion systems, coupled with the possibility of improving their ecological sustainability. Performance of hybrid electric aircraft are affected by the sizes and weights of propulsion systems typically constituted of internal combustion engines and electric motors. Therefore, the correct design of propulsive architectures is fundamental to ensure a desired state of charge target level of batteries compliant with the flight plan provided by a driver unit. A Linear Time Variant Model Predictive Control (LTV-MPC) strategy for energy management purposes of an aeronautical hybrid powertrain is proposed in the present work. The MPC, designed as a supervisor, provides the best trade-off between command torques of motors belonging to a parallel-hybrid propulsion system to guarantee the final state of charge as close as possible to the
Fornaro, EnricoTordela, Ciro
In the mobility industry, Fuel Cell Electric Vehicle (FCEV) combines fuel cell technology with batteries, allowing to overcome some limitations of Battery Electric Vehicles (BEVs), such as the high recharging time and the high battery mass for applications requiring a high amount of energy (e.g., bus and heavy-duty vehicles). FCEVs have the possibility to collect several information from Intelligent Transportation Systems (ITSs) with relevant potential for vehicle efficiency improvement. Indeed, an online vehicle speed prediction inherently considering real-life factors such as traffic flow, driving path and driving style, allows for novel designs of Energy Management Systems (EMSs) for the optimal operations of the hybrid propulsion system. In such context, this paper proposes an EMS based on Stochastic Model Predictive Control with Learning (SMPCL) to optimize the hydrogen consumption of a Fuel Cell Electric Vehicle (FCEV), while guaranteeing the fulfillment of constraints on battery
Alfieri, VincenzoBinetti, GiulioRuotolo, RomualdoGandino, Edoardo
In the shipbuilding industry, the employment of hybrid propulsion systems is increasingly common on-board vessels for making more eco-sustainable boat traffic in marine waters. Energy management systems are required to ensure the culling of fuel consumption and the preservation of batteries by monitoring their state of charge in hybrid powertrains, coupled with the possibility of performing the sea path desired by a driver unit. A Model Predictive Control (MPC) supervisor is proposed in the present work for managing a marine parallel-hybrid propulsion system in terms of handling the state of charge of batteries and the driving cycle imposed by the boat driver. Specifically, the MPC is employed to avoid excessive electric energy consumption observable as a reduced loss in terms of the state of charge of batteries by selecting the best amount of command torques related to two electric motors and one internal combustion engine of the considered powertrain. A lumped parameters model of a
Tordela, CiroFornaro, Enrico
The Wankel engine is an eccentric rotary internal combustion engine known for its simplicity, compactness, reliability, and efficiency. However, issues related to sealing, efficiency, and emissions have hindered its widespread use. Recent advancements in sealing technology, novel designs, material coatings, and alternative fuels have addressed some of these problems, leading to improvements in Wankel engine performance. This study examines these advancements in Wankel engine technology and proposes three potential applications for future automotive use. The first application involves utilizing a Wankel engine with a continuously variable transmission to replace the powertrain in conventional vehicles. The second application suggests replacing the engine in a series-parallel electric-hybrid architecture with a Wankel engine. Lastly, the third application explores using a Wankel engine as a range extender for electric vehicles. To evaluate the benefits in terms of fuel consumption for
Mittal, VikramShah, RajeshPrzyborowski, Alexandra
High-efficient simulations are mandatory to manage the ever-increasing complexity of automotive powertrain system and reduce development time and costs. Integrating AI methods into the development process provides an ideal solution thanks to massive increase in computational power. Based on an 1D physical engine model of a turbo-charged direct injection gasoline engine with variable valve timing (VVT), a high-performance hybrid simulation model has been developed for increasing computing performance. The newly developed model is made of a physics-based low-pressure part including intake and exhaust peripheries and a neural-network-based high-pressure part for combustion chamber calculations. For the training and validation of the combustion chamber neural networks, a data set with 10.5 million operating points was generated in a short time thanks to the parallelizable combustion chamber simulations in stand-alone mode. The data set covers wide variation ranges of boundary and operating
Wei, JingsiLiu, MingjiaAngerbauer, MichaelYang, QiruiXu, HanjunGrill, MichaelKulzer, AndréChen, Ceyuan
Internal combustion engines fall under increased environmental and social pressure. However, they will still play an important role in future transport, especially in hybrid propulsion systems. As a consequence, efficiency of SI engines has to be further increased. Lean burn operation provides a promising way to reach this target. An extremely downsized SI single cylinder research engine is used for the investigations. The engine features a stroke-to-bore ratio of 1.5, leading to higher piston speeds and hence increased tumble motion. The resulting increase in turbulent flame speed supports sufficient combustion performance of diluted mixtures. Although the mentioned provisions increase combustion stability for lean burn operation the reachable relative air/fuel ratio is limited. In order to extend the lean burn capabilities of the engine (λ ≥ 2.0) and further exploit the efficiency advantages of this combustion process the engine is upgraded with a hydrogen port fuel injection. With
Wenz, ErichEilts, Peter
As part of its path to carbon neutrality, Kubota Engine engineers have developed a new 3.8-liter hydrogen engine that was introduced at CONEXPO 2023 in Las Vegas. The 4-cylinder spark-ignited engine employs port fuel-injection and provides 85 kW (114 hp), which is the output required for a 45-kVA generator, the company notes. Kotaro Shiozaki, PR manager, Industrial Engine at Kubota Corp., said that hybrid powertrains also are an effective solution for reducing CO2 from industrial engines, and he's confident they will be more than just an interim solution. Kubota displayed three hybrid solutions: a P0 micro-hybrid that will be available later this year, a P1 hybrid that provides brief periods of motor assist when high output is required and a P2 hybrid engine scheduled for production in 2025 that offers electric-motor drive.
Gehm, Ryan
SAE/USCAR-46 defines test methods and outputs for engine oil pump bench testing. Performance and durability testing are the primary focus of this standard. This is written to specifically address testing of electronically controlled variable displacement pumps but can be adapted to mechanically controlled pumps and other pump technologies as needed. This standard outlines critical inputs and outputs in order to perform the testing and report results, but does not specifically set the acceptance standards or pass/fail criteria. Acceptance criteria must be set by the customer.
null, null
Among the myriad of potential hybrid powertrain architectures, selecting the optimal for an application is a daunting task. Whenever available, computer models greatly assist in it. However, some aspects, such as pollutant emissions, are difficult to model, leaving no other option than to test. Validating plausible options before building the powertrain prototype has the potential of accelerating the vehicle development even more, doing so without shipping components around the world. This work concerns the design of a system to virtually couple—that is, avoiding physical contact—geographically distant test rigs in order to evaluate the components of a powertrain. In the past, methods have been attempted, either with or without assistance of mathematical models of the coupled components (observers). Existing methods are accurate only when the dynamics of the systems to couple are slow in relation to the communication delay. Also, existing methods seem to overlook the implications of
Ametller, AdriaBrace, Chris
Allison Transmission Indianapolis, IN 317-242-5000
Although the brake thermal efficiency of the state-of-the-art Atkinson-cycle hybrid engines have reached 41%, such engines typically have a low specific power. The ideal hybrid engines for SUVs should have a high thermal efficiency as well as a high specific power. Jiangling Motors recently developed a 4-cylinder, 1.5L TGDI hybrid Miller engine for powering mid-size SUVs, which has achieved 42% brake thermal efficiency, 19.3-bar BMEP, and 73.3-kW/L specific power. The engine has a high compression ratio, a long stroke, and is equipped with a low-pressure EGR system. It can operate with the stoichiometric mixture on the full engine map, with the help of the water-cooled exhaust manifold and the intelligent thermal management system.
Liu, YongLiao, ShanbinZheng, YueweiChen, BinMiao, RuigangZeng, CuiweiOuyang, XianlinCai, XingqiYang, YanhuaZeng, HonglianCao, LimingTeng, Ho
Benchmark Space Systems Burlington, VT 678-576-6126
The efficiency of Hybrid Electric Vehicles (HEVs) may be substantially increased if the unexpanded exhaust gas energy is efficiently recovered and employed for vehicle propulsion. This can be accomplished employing a properly designed exhaust gas turbine connected to a suitable generator whose output electric energy is stored in the vehicle storage system; a new hybrid propulsion system is hence delineated, where the power delivered by the main engine is combined to the power produced by the exhaust gas turbo-generator: previous studies, carried out under some simplifying assumptions, showed potential vehicle efficiency increments up to 15% with respect to a traditional turbocharged engine. Given the power target of the required exhaust gas turbo-generator, no commercial or reference product could be considered: on account of this, in the preliminary evaluations, the turbine efficiency was assumed constant. In this paper instead the authors present the result of new evaluations
Pipitone, EmilianoCaltabellotta, SalvatoreBeccari, StefanoLanzafame, RosarioMauro, StefanoBrusca, Sebastian
With ever stricter legislative requirements for CO2 and other exhaust emissions, significant efforts by OEMs have launched a number of different technological strategies to meet these challenges such as Battery Electric Vehicles (BEVs). However, a multiple technology approach is needed to deliver a broad portfolio of products as battery costs and supply constraints are considerable concerns hindering mass uptake of BEVs. Therefore, further investment in Internal Combustion (IC) engine technologies to meet these targets are being considered, such as lean burn gasoline technologies alongside other high efficiency concepts such as dedicated hybrid engines. Hence, it becomes of sound reason to further embrace diversity and develop complementary technologies to assist in the transition to the next generation hybrid powertrain. One such approach is to provide increased valvetrain flexibility to afford new degrees of freedom in engine operating strategies. Freevalve is an electro-hydraulic
Elmagdoub, Abdelrahman Waleed MohamedMöller, AndreasCarlson, UrbanBrace, ChrisAkehurst, SamTurner, JamesZhang, Nic
The application of electric power for aircraft propulsion can take a variety of forms, ranging from partial electric to full electric. The introduction of electric engines to drive propulsors, along with the variety of available methods to generate electricity and store energy offers great degree of new design freedom for next-generation aircraft and aircraft architectures. This newfound design freedom exposes a need within the aviation industry to establish a common design language for electrified propulsion. While this need for a common design language is recognized, the intent of this document is to encourage innovation, providing reference architectures as a launching point for future work in this area. This document will describe potential electrified propulsion architectures and provide examples. While providing these example architectures, this document will develop common definitions for the elements of the architectures by defining: 1 The elements of electrified propulsion
E-40 Electrified Propulsion Committee
Vehicle manufacturers are experiencing a shift in legislation and customer attitudes towards powertrain technologies. To support the pathway towards net-zero emissions by 2050, technologies that significantly reduce CO2 emissions will be needed. This will require increasing levels of electrification, and in the areas of compact cars and urban transportation, the adoption of pure battery electric powertrains is expected to become the dominant technology. For large passenger cars and light commercial vehicles (LCVs) meeting all customer requirements, including range, payload, towing capability, and purchase cost with a pure electric vehicle is challenging and requires the use of heavy and expensive battery packs, which have a high embedded CO2 content. The study builds on the work previously presented on the MAHLE modular hybrid powertrain (MMHP) concept and examines the suitability of this powertrain configuration to meet the future needs of large passenger cars and LCVs. In the MMHP
Harrington, AnthonyBassett, MichaelCooper, AdrianBlaxill, Hugh
In Plug in hybrid electric vehicles (PHEVs), the management of the main drivetrain components and the shift between pure electric and hybrid propulsion is decided by the on-board energy management system (EMS). The EMS decisions have a direct impact on CO2 emissions and need to be optimized to achieve as low emissions as possible. This paper presents optimization methods for EMS algorithms of a parallel P2 PHEV. Two different supervisory control algorithms are examined, employing simulations on a validated PHEV platform. An Equivalent Consumption Minimization Strategy (ECMS) algorithm is implemented and compared to a rule-based one, the latter derived by back-engineering of available experimental data. The different EMS algorithms are analyzed and compared on an equal basis in terms of distance, demanded energy and state of charge levels over different driving cycles. A sensitivity analysis on component sizing interaction with algorithm performance is conducted to check robustness of
Aletras, NikolaosDoulgeris, StylianosSamaras, ZissisNtziachristos, Leonidas
Advanced features in automotive systems often necessitate the management of complex interactions between subsystems. Existing control strategies are designed for certain levels of robustness, however their performance can unexpectedly deteriorate in the presence of significant uncertainties, resulting in undesirable system behaviors. This limitation is further amplified in systems with complex nonlinear dynamics. Hydro-mechanical clutch actuators are among those systems whose behaviors are highly sensitive to variations in subsystem characteristics and operating environments. In a P2 hybrid propulsion system, a wet clutch is utilized for cranking the engine during an EV-HEV mode switching event. It is critical that the hydro-mechanical clutch actuator is stroked as quickly and as consistently as possible despite the existence of uncertainties. Thus, the quantification of uncertainties on clutch actuator behaviors is important for enabling smooth EV-HEV transitions. In this paper, a
Yang, HangFujii, YujiZhang, YijingHaria, HiralDevendran, Ram SudarsanSaini, AnkitGorodetsky, AlexWang, Kon-Well
Accurate determination of driveshaft torque is desired for robust control, calibration, and diagnosis of propulsion system behaviors. The real-time knowledge of driveshaft torque is also valuable for vehicle motion controls. However, online identification of driveshaft torque is difficult during transient drive conditions because of its coupling with vehicle mass, road grade, and drive resistance as well as the presence of numerous noise factors. A physical torque sensor such as a strain-gauge or magneto-elastic type is considered impractical for volume production vehicles because of packaging requirements, unit cost, and manufacturing investment. This paper describes a novel online method, referred to as Virtual Torque Sensor (VTS), for estimating driveshaft torque based on Machine-Learning (ML) approach. VTS maps a signal from Inertial Measurement Unit (IMU) and vehicle speed to driveshaft torque. The unique advantage is that VTS does not explicitly rely on the first principles
Zhang, YijingChen, FengyiChen, WeitianBichkar, AkshaySullivan, ConorSaini, AnkitNagadi, ThirumalLeads, MichaelRiedle, BradleyFujii, Yuji
The electrification of powertrains provides a critical opportunity to change the way that engines are designed and developed, allowing their efficiency to be increased and their cost reduced. This paper draws on ongoing Ricardo projects in the field of dedicated hybrid engines (DHEs). The Magma xEV combustion concept employs very high compression ratio, long stroke architecture, and advanced ignition and knock mitigation technologies, for DHEs requiring the highest efficiency. In the latest research project a pre-chamber combustion system (with both active and passive operation) has been applied to the Magma xEV engine, in order to enable the highest levels of charge dilution and further increase brake thermal efficiency. The research focussed on benefits of pre-chamber ignition as compared to conventional spark ignition and corona discharge ignition. The comparison of charge dilution using excess air (lean operation) and exhaust gas recirculation are presented. A route to brake
Saroop, AgamOsborne, RichardStokes, JohnValenta, LukášPenning, Richard
Upcoming, increasingly stringent greenhouse gas (GHG) as well as emission limits demand for powertrain electrification throughout all vehicle applications. Increasing complexity of electrified powertrain architectures require an overall system approach combining component technology with integration and industrialization requirements when heading for further significant efficiency optimization of the subsystem internal combustion engine. The requirements on the combustion engine in hybrid powertrains are quite different to those in a conventional powertrain solution. Next-generation hybrid engines, with brake thermal efficiency (BTE) targets starting from 42-43% and aiming for 45% and above within the product lifecycle, require a re-thinking of the base engine architecture of current modular engine platforms. At the same time focus on the product cost and minimized additional investment demand reuse of current production, machining and assembly facilities as far as possible. A modular
Schoeffmann, WolfgangKapus, PaulHowlett, MichaelSams, Christoph
For achieving decarbonization in internal combustion engines, a utilization of carbon neutral fuels from renewable energies (e-fuel) could be one option. E-fuel is expected to be implemented as blended fuels with conventional fuels, which results in more uncertainties of the fuel properties. To cope with a larger number of blended fuels compared to the existing alcohol-fuel blends, fuel aging effects resulting from longer refueling intervals in hybrid engines, and fuel blend variations in each refueling station, an optimized engine control and energy management depending on the fuel blend contents will be required. In this study, a new fuel contents estimation method for the engine control based on the external refueling information and the signals of the existing engine sensors is developed, by utilizing data assimilation. With the non-linear ensemble Kalman filter, the prediction model which predicts changes of the fuel blending rate in the tank considering the refueling and fuel
Yoneya, NaokiAmaya, Kenji
To achieve higher brake thermal efficiency (BTE) and improve vehicle economy, the new development of dedicated hybrid engine (DHE), adopting the Atkinson or Miller cycle, has been becoming the current development trends. A base 1.5L natural aspiration (NA) engine with deep Atkinson cycle has been developed for dedicated hybrid vehicle application, which can achieve the highest BTE of 41.19%. In order to achieve higher BTE, several potential technologies which are easy for mass production application have been studied progressively, such as, higher compression ratio (CR), optimized exhaust gas recirculation (EGR) pick point, lower EGR temperature, higher EGR rate, higher RON number fuels, heat transfer reduction by polishing valve head, light boost, lower viscosity oil. The results show the combined technology application can achieve the highest engine BTE of 42.59%. This paper provides the studied technical routine and the achieved benefits step by step.
Pan, ShiyiWang, JinhuaHuang, Zuohua
BYD recently introduced its new DM-i (Dual Mode-Intelligent) plug-in hybrid architecture with a new dedicated 1.5NA (Naturally Aspirated) high-efficiency engine, which can reach a peak of 43% brake thermal efficiency. With this architecture, the vehicle is mainly driven by motors and engine only starts when required. This requires that once started, the engine can reach its best working temperature as quick as possible. To achieve this target, a new intelligent thermal management system was designed. This system adopted an advanced split cooling strategy to control the flow ratio between cylinder block and head, which was realized by the combination of one electronic thermostat and one wax thermostat. An electronic water pump was used to actively control the coolant flow rate. Together with the intelligent control of thermal needs under all working conditions, the new thermal management system realized the following benefits: faster engine warm-up, better fuel economy and lower
lu, GuoxiangYang, DongshengRong, YulongGong, ZewenWang, Bo
Individual transport plays a considerable role in global greenhouse gas emissions. Hence, worldwide legislation increases the demands on the automotive industry with regard to emissions. Because internal combustion engines will likely play an important role in the future transport, particularly in hybrid propulsion systems, further improvement of the combustion system is necessary. Therefore, the potential of lean burn combustion in combination with other technologies is investigated. The primary focus is on the improvement of SI engine efficiency. For the investigations conducted, an extremely downsized SI single cylinder research engine is upgraded with various engine technologies. The stroke-to-bore ratio is increased to 1.5, leading to higher piston speeds. The resulting increase in tumble and hence turbulent flame speed supports the combustion performance of highly diluted mixtures. In order to further increase the thermodynamic efficiency, miller timings are realised in the form
Wenz, ErichPauls, AlexanderThielen, MarvinTodt, ArneEilts, Peter
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