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Viewing 211 to 240 of 110718
2017-10-08
Technical Paper
2017-01-2201
Zhongye Cao, Tianyou Wang, Kai Sun, Lei Cui, Yong Gui
Abstract For uniflow scavenged two-stroke marine diesel engines, the main function of scavenging process is to replace the burned gas with fresh charge. The end state of scavenging process is integral to the subsequent compression and combustion, thereby affecting the engine’s fuel economy, power output and emissions. In this paper, a complete working cycle of a large marine diesel engine was simulated by using the 3D-CFD software CONVERGE. The model was validated by mesh sensitivity test and experiment data. Based on this calibrated model, the influences of swirl ratio and exhaust valve closing (EVC) timing on the scavenging process were investigated. The parameters evaluating the performance of scavenging process were introduced. The results show that, by adjusting the swirl orientation angle(SOA) from SOA=10° to SOA=30°, different swirl ratios are generated and have obvious differences in flow characteristics and scavenging performance.
2017-10-08
Technical Paper
2017-01-2200
Peter Priesching, Mijo Tvrdojevic, Ferry Tap, Casper Meijer
Abstract Turbulent combustion modeling in a RANS or LES context imposes the challenge of closing the chemical reaction rate on the sub-grid level. Such turbulent models have as their two main ingredients sources from chemical reactions and turbulence-chemistry interaction. The various combustion models then differ mainly by how the chemistry is calculated (level of detail, canonical flame model) and on the other hand how turbulence is assumed to affect the reaction rate on the sub-grid level (TCI - turbulence-chemistry interaction). In this work, an advanced combustion model based on tabulated chemistry is applied for 3D CFD (computational fluid dynamics) modeling of Diesel engine cases. The combustion model is based on the FGM (Flamelet Generated Manifold) chemistry reduction technique. The underlying chemistry tabulation process uses auto-ignition trajectories of homogeneous fuel/air mixtures, which are computed with detailed chemical reaction mechanisms.
2017-10-08
Technical Paper
2017-01-2202
Shiyou Yang
Abstract This work presents an application of two sub-models relative to chemical-kinetics-based turbulent pre-mixed combustion modeling approach on the simulation of burn rate and emissions of spark ignition engines. In present paper, the justification of turbulent pre-mixed combustion modeling directly based on chemical kinetics plus a turbulence model is given briefly. Two sub-models relative to this kind of pre-mixed combustion modeling approach are described generally, including a practical PRF (primary reference fuel) chemical kinetic mechanism which can correctly capture the laminar flame speed under a wide range of Ford SI (spark ignition) engines/operating conditions, and an advanced spark plug ignition model which has been developed by Ford recently.
2017-10-08
Technical Paper
2017-01-2205
Velmurugan M A, MahendraMohan Rajagopal
Abstract Agricultural tractors are often subjected to various applications like front end loading work, cultivation work, where frequent forward and reverse gears are needed. Most of Indian agricultural tractors are equipped with mechanical transmission system which demands repeated clutching and de-clutching operation for such applications resulting in increased operator fatigue and lesser productivity. Also need of electronics in Indian agricultural industry for better farm mechanization is growing high. This research work depicts development of electronic bi-directional shifting (power shuttle) control design and calibration for farm vehicle fitted with wet clutch transmission. This research also reduces operator fatigue via frequent directional shift through electronic transmission. The control system is designed without any electronic interfacing with engine and also provides clutch-less gear shifting and auto-launch which offers ease to drive even for novice driver.
2017-10-08
Technical Paper
2017-01-2209
Christian Ibron, Mehdi Jangi, Tommaso Lucchini, Xue-Song Bai
Partially premixed combustion (PPC) can be applied to decrease emissions and increase fuel efficiency in direct injection, compression ignition (DICI) combustion engines. PPC is strongly influenced by the mixing of fuel and oxidizer, which for a given fuel is controlled mainly by (a) the fuel injection, (b) the in-cylinder flow, and (c) the geometry and dynamics of the engine. As the injection timings can vary over a wide range in PPC combustion, detailed knowledge of the in-cylinder flow over the whole intake and compression strokes can improve our understanding of PPC combustion. In computational fluid dynamics (CFD) the in-cylinder flow is sometimes simplified and modeled as a solid-body rotation profile at some time prior to injection to produce a realistic flow field at the moment of injection. In real engines, the in-cylinder flow motion is governed by the intake manifold, the valve motion, and the engine geometry.
2017-10-08
Technical Paper
2017-01-2208
Tao Liu, Ziwang Lu, Guangyu Tian
Abstract To further explore the potential of fuel economy for hybrid electric vehicle (HEV), a methodology of demand power optimization is proposed. The fuel consumption depends not only on the EMS, but also on the way to operate vehicle. A control strategy to adjust driver’s demand before power splitting is necessary. To get accurate and reliable control strategy, two aspects are the most important. First, a rigorous and organized modeling approach is a base to describe complicated powertrain system of HEV. The energetic macroscopic representation (EMR) is a graphical synthetic description of electromechanical conversion system based on energy flow. A powertrain architecture of HEV is described explicitly via the EMR. Second, the effectiveness of EMS and the reasonability of driving operations are vital.
2017-10-08
Technical Paper
2017-01-2211
Mengqiu Jia, Zhen Lu, Tianyou Wang, Yufeng Li, Yanzhe Sun, Ming Wen, Zhizhao Che, Kai Sun
Abstract The intake process plays an important role in the operation of internal combustion engines. In the present study, a three-dimensional transient simulation of a four-valve diesel engine was performed using Large Eddy Simulation (LES) model based on software CONVERGE. The mean velocity components in three directions through the intake valve curtain, the flow separation around the intake valves, the influences of inlet jet on turbulence flow field and cycle-to-cycle variation were investigated in this work. The result shows that the mean velocity distributes non-uniformly near the valve curtain at high valve lifts. In contrast, the mean velocity distribution is uniform at low valve lifts. It is found that the flow separation occurs at valve stem, valve seat and valve sealing through the outlet of the helical port. In contrast, flow separation is only observed in the valve seat through the outlet of the tangential port.
2017-10-08
Technical Paper
2017-01-2210
Masayoshi Matsuda, Takeshi Yokomori, Norimasa Iida
Abstract The thermal efficiency of a spark-ignition (SI) engine must be improved to reduce both environmental load and fuel consumption. Although lean SI engine operation can strongly improve thermal efficiency relative to that of stoichiometric SI operation, the cycle-to-cycle variation (CCV) of combustion increases with the air dilution level. Combustion CCV is caused by CCVs of many factors, such as EGR, spark energy, air-fuel ratio, and in-cylinder flow structure related to engine speed. This study focuses on flow structures, especially the influence of a tumble structure on flow fluctuation intensity near ignition timing. We measured the flow field at the vertical center cross section of an optically accessible high-tumble flow engine using time-resolved particle image velocimetry.
2017-10-08
Technical Paper
2017-01-2213
Satoshi Hokimoto, Tatsuya Kuboyama, Yasuo Moriyoshi, Minoru Iida, Takahiro Watanabe
Abstract Reduction in the cycle-to-cycle variation (CCV) of combustion in internal combustion engines is required to reduce fuel consumption, exhaust emissions, and improve drivability. CCV increases at low load operations and lean/dilute burn conditions. Specifically, the factors that cause CCV of combustion are the cyclic variations of in-cylinder flow, in-cylinder distributions of fuel concentration, temperature and residual gas, and ignition energy. However, it is difficult to measure and analyze these factors in a production engine. This study used an optically accessible single-cylinder engine in which combustion and optical measurements were performed for 45 consecutive cycles. CCVs of the combustion and in-cylinder phenomena were investigated for the same cycle. Using this optically accessible engine, the volume inside the combustion chamber, including the pent-roof region can be observed through a quartz cylinder.
2017-10-08
Technical Paper
2017-01-2212
Jun Peng, Mingyang Ma, Wang Weizhi, Fu-qiang Bai, Qing Du, F Zhang
Abstract High-pressure common rail (HPCR) fuel injection system is the most widely used fuel system in diesel engines. However, when multiple injection strategy is used, the pressure wave fluctuation is un-avoided due to the opening and closing of the needle valve which will affect the subsequent fuel injection and combustion characteristics. In this paper, several parameters: injection pressure, injection intervals, the main injection pulse widths are investigated on a common rail fuel injection test rig with two injection pulses to explore their effect on the fuel injection rate and fuel quantity. The result showed that the longer injection interval between the pilot and main injections will lead to a rail pressure drop at the beginning of the main injection so that a smaller fuel quantity will be delivered. The main injection pulse width also influences fuel injection rate and the main fuel quantity.
2017-10-08
Technical Paper
2017-01-2216
Yumin Fu
Abstract This study presents the development of sensor less rough road detection by using frequency analysis of instantaneous crankshaft rotation speed signal. Combustion diagnosis (misfire detection) is enforced by OBD requirement. Eliminating rough road’s effect on misfire detection is critical for getting robust diagnosis result, especially for crankshaft rotation speed based misfire detection. Although some kind of sensor is often used to identify vehicle driving on rough road, sensor less rough road detection method is still attractive for OEM to reduce cost and some approaches have been developed in past years for the aim [1] [2] [3]. This paper presents a new rough road detection approach based on crankshaft rotation speed frequency domain analysis. It firstly collects the signal from vehicle driving with misfire on public road and without misfire on rough road. Fluctuation exists in crankshaft rotation speed under such condition.
2017-10-08
Technical Paper
2017-01-2217
Fushui Liu, Ning Kang, Yikai Li, Pei Wang
Abstract The electronic unit pump system, which is widely applied to the heavy-duty diesel engine, belongs to the pulsating high-pressure fuel injection system, and the fuel pressure fluctuations have an essential influence on the spray and combustion in the internal combustion engine. Besides, pressure fluctuations are always aroused by the motion of actuators, such as the injector or other control valves, so it is also an advantage for fault diagnosis and feedback control to ascertain the relationship between the pressure fluctuation and the motion of the actuator. In this study, experiments and 1D-simulation were carried on to investigate the fuel pressure fluctuation characteristics and their correlations with the transient motion of the needle valve in the injector.
2017-10-08
Technical Paper
2017-01-2214
Kwee-Yan Teh, Penghui Ge, Yusheng Wang, David Hung
Abstract The large-scale rotating flow structure in an engine cylinder exhibits features that can be described in generic terms of tumble and swirl. The structural details, nevertheless, vary from cycle to cycle due to fluctuating initial and boundary conditions of the flow. Typical analysis of the flow field cyclic variability - by simple root-mean-square, or additional spatial or temporal filtering, or proper orthogonal decomposition - is based on pointwise deviation of the instantaneous velocity from the ensemble mean. However, that analysis approach is not amenable to the evaluation of spatial variation of the flow structure, in position and orientation, within the flow field. To this end, other studies in the past focused instead on quantifying the variation of the vortex center for the dominant tumble or swirl pattern within the flow field.
2017-10-08
Technical Paper
2017-01-2215
Mingming Ma
Abstract A lubricating system modeling method based on flight test data is proposed in this paper. ANN model based on a large number of flight test data is trained and validated, and models of 6 lubricating system parameters in all engine operation settings and whole flight envelope are established. Model results are in good agreement with flight test results, which shows feasibility and effectiveness of the presented modeling method. The model results are packaged in dynamic link library, and the coordination between calculating model and GDAS is accomplished. Comparison of model and flight test results in real-time monitoring of flight test comes true, thus on-line trend monitoring of oil parameters is implemented and applied. Additionally, input parameters are gradually decreased as new input parameter group of ANN structure. Oil parameter model is trained and validated again with the new group of parameters, until leading to unacceptable bias between model and flight test results.
2017-10-08
Technical Paper
2017-01-2221
Peixuan Zeng, Penghao Zhang, Binyu Mei, Shiping Huang, Gangfeng Tan
Abstract It’s not easy to start the engine in winter, especially in frigid highlands, because the low temperature increases the fuel’s viscosity, decreasing the lubricating oil flow ability and the storage performance of battery. Current electrical heating method can improve the engine starting performance in low temperature condition, but this method adds an external power to the engine, leading to the engine cannot maintain an efficient energy utilization. A warming device using the solar energy is designed to conserve the energy during the daytime, and directly warm up the engine at the time when the engine turns off for a long time, especially during the night. A solar collector installed on the top of the vehicle is used to convert the solar energy to the thermal energy, which is then transferred to the heat accumulator that contain the phase-change medium which can increase the heat storage performance.
2017-10-08
Technical Paper
2017-01-2222
ZhenYang Liu, Xihui Wang
Abstract The ever increasing popularity of electric vehicles and higher requirement on safety and comfort has led heat pump air conditioning system indispensable in electric vehicle. Many studies have shown that the addition of nano particles contributes to great improvement on thermal conductivity than that of conventional refrigerants. Therefore, the application of the magnetic nanorefrigerant in heat pump air conditioning system has massive potential to heighten the heat transfer efficiency. This paper aims at studying the magnetic nanorefrigerant comprised of the magnetic nano powder Fe3O4 and refrigerant R134a. According to the relevant theoretical analyses and empirical formula, the heat transfer coefficient, density, viscosity, and other physical parameters are calculated approximately.
2017-10-08
Technical Paper
2017-01-2218
Roman Varbanets, Sergey Karianskyi, Sergey Rudenko, Igor V. Gritsuk, Aleksey Yeryganov, Olena Kyrylash, Nadezhda Aleksandrovskaya
Abstract Operability and efficiency of transport diesel engines significantly depend on periodical diagnosis of its technical condition. The article considers the features of monitoring and diagnostic of transport diesel engines with the help of vibroacoustic analysis of high pressure fuel equipment and gas distribution mechanism. Functional scheme of diagnostic system and analytical method of TDC determination is described. Article gives an example of four-stroke and two-stroke diesel engines diagnosis. Also the article shows turbocharger speed determination and diagnosis with the help of vibroacoustic spectrum analysis. The main feature of the given methods is their high efficiency for diagnosis of transport diesel engines during operation.
2017-10-08
Technical Paper
2017-01-2219
Xihui Wang
Abstract The conventional cooling fluids in vehicle engine cooling water jacket have relatively poor heat transfer performance. The key to enhance heat transfer in cooling-jacket is to research a kind of new coolants. Nanofluids have heat transfer enhancement merits. In present study, the numerical simulation on Fe3O4 nanofluid flow in cooling water jacket of Gasoline direct injection engine was performed using computational fluid dynamics ( CFD) software FLUENT. The heat transfer coefficient of nanofluids was calculated and verified by experiment. Fe3O4 nano-particles were used in mixture of water/ethylene glycol as a base fluid. The thermal performance of the nanofluid was studied, also the thermal performance of a cooling-jacket was studied with CFD technology. The simulation was performed for different volumetric concentrations of(1%,2%,5%) nanofluids at different engine speeds. The results showed that heat transfer enhanced compared to the base fluid.
2017-10-08
Technical Paper
2017-01-2229
Byeongsoek Lee, Heechang Oh, SeungKook Han, SooHyung Woo, JinWook Son
Abstract The maximum thermal efficiency of gasoline engine has been improving and recently the maximum of 40% has been achieved. In this study, the potential of further improvement on engine thermal efficiency over 40% was investigated. The effects of engine parameters on the engine thermal efficiency were evaluated while the optimization of parameters was implemented. Parameters tested in this study were compression ratio, tumble ratio, twin spark configuration, EGR rate, In/Ex cam shaft duration and component friction. Effects of each parameter on fuel consumption reduction were discussed with experimental results. For the engine optimization, compression ratio was found to be 14, at which the best BSFC without knock and combustion phasing retardation near sweet spot area was showed. Highly diluted combustion was applied with high EGR rate up to 35% for the knock mitigation.
2017-10-08
Technical Paper
2017-01-2223
Vikram Singh, Per Tunestal, Martin Tuner
Abstract In recent years, stricter regulations on emissions and higher demands for more fuel efficient vehicles have led to a greater focus on increasing the efficiency of the internal combustion engine. Nowadays, there is increasing interest in the recovery of waste heat from different engine sources such as the coolant and exhaust gases using, for example, a Rankine cycle. In diesel engines 15% to 30% of the energy from the fuel can be lost to the coolant and hence, does not contribute to producing work on the piston. This paper looks at reducing the heat losses to the coolant by increasing coolant temperatures within a single cylinder Scania D13 engine and studying the effects of this on the energy balance within the engine as well as the combustion characteristics. To do this, a GT Power model was first validated against experimental data from the engine.
2017-10-08
Technical Paper
2017-01-2224
Paul Freeland, Gareth Jones, Rong-Sheih Chen, Liang-Wei Huang, Marwan El-Kassem, Roland Kaiser
Abstract The paper outlines the fuel consumption benefits available from de-throttling technologies that can help to bring gasoline engine efficiency on a par with that of diesel engines. The paper shows the relative efficiency improvements offered by a fully-variable intake valve lift system in conjunction with wide-range cam phasers, which also incorporate the facility to provide zero valve lift to enable cylinder deactivation. Testbed results recorded with a prototype concept engine show the degree to which early intake valve closing, valve overlap and cylinder deactivation can work together, and the limitations of this synergy at different operating conditions.
2017-10-08
Technical Paper
2017-01-2233
Gautam Kalghatgi, Kai Morganti, Ibrahim Algunaibet
Knock in spark ignition engines is stochastic in nature. It is caused by autoignition in hot spots in the unburned end-gas ahead of the expanding flame front. Knock onset in an engine cycle can be predicted using the Livengood-Wu integral if the variation of ignition delay with pressure and temperature as well as the pressure and temperature variation with crank angle are known. However, knock intensity (KI) is determined by the evolution of the pressure wave following knock onset. In an earlier paper (SAE 2017-01-0689) we showed that KI can be approximated by KI = Z (∂T/∂x)-2 at a fixed operating condition, where Z is a function of Pko, the pressure, and (∂T/∂x) is the temperature gradient in the hot spot at knock onset. Then, from experimental measurements of KI and Pko, using five different fuels, with the engine operating at boosted conditions, a probability density function for (∂T/∂x) was established.
2017-10-08
Technical Paper
2017-01-2230
Nizar F.O. Al-Muhsen, Guang Hong
Abstract Ethanol as a renewable fuel has been used widely in vehicles. Dual fuel injection is one of the new techniques in development for increasing the engine’s thermal efficiency and reducing the pollutant emissions. This study reports experimental investigation to the dual ethanol fuel injection with a focus on the effect of spark timing on the engine performance at different volumetric ratios of ethanol directly injected to ethanol port injected. Experiments were conducted on a single cylinder 250cc spark ignition engine at two engine loads and 3500 RPM. The spark timing was varied from 15 to 42 CAD bTDC at the light load and from 15 to 32 CAD bTDC at the medium load, while the volumetric ratio of direct injection (DI%) was varied from 0% to 100%.
2017-10-08
Technical Paper
2017-01-2237
K. Gopal Duleep
Abstract / Introduction The overall objectives of this study are to establish the relationship between a spark ignition, or Otto cycle, engine energy efficiency and the octane number (and potentially, the composition) of the fuel through a comprehensive review of recently published literature. The efficiency of the ideal Otto cycle is a function of the compression ratio (CR), but increasing compression ratio is limited by the onset of knock, which can be prevented by increasing fuel octane number. Hence, in an ideal case, there is a direct connection between engine efficiency and fuel octane number. In the real world, other factors also contribute to the relationship and spark timing is the primary control variable that affects both knock and efficiency. The literature review found that the relationship between octane number and efficiency was influenced by a number of intermediate variables covering engine type, operating condition, and fuel formulation.
2017-10-08
Technical Paper
2017-01-2236
Mateos Kassa, Carrie Hall, Fabien Vidal-Naquet, Thomas Leroy
Abstract In this study, the impact of the intake valve timing on knock propensity is investigated on a dual-fuel engine which leverages a low octane fuel and a high octane fuel to adjust the fuel mixture’s research octane rating (RON) based on operating point. Variations in the intake valve timing have a direct impact on residual gas concentrations due to valve overlap, and also affect the compression pressure and temperature by altering the effective compression ratio (eCR). In this study, it is shown that the fuel RON requirement for a non-knocking condition at a fixed operating point can vary significantly solely due to variations of the intake valve timing. At 2000 rpm and 6 bar IMEP, the fuel RON requirement ranges from 80 to 90 as a function of the intake valve timing, and the valve timing can change the RON requirement from 98 to 104 at 2000 rpm and 14 bar IMEP.
2017-10-08
Technical Paper
2017-01-2235
Ting Liu, Fuyuan Zhang, Yuedong Chao, Zongjie Hu, Liguang Li
Abstract In order to investigate the impacts of recirculated exhaust gas temperature on gasoline engine combustion and emissions, an experimental study has been conducted on a turbocharged PFI gasoline engine. The engine was equipped with a high pressure cooled EGR system, in which different EGR temperatures were realized by using different EGR coolants. The engine ran at 2000 r/min and 3000 r/min, and the BMEP varied from 0.2MPa to 1.0MPa with the step of 0.2MPa. At each case, there were three conditions: 0% EGR, 10% LT-EGR, 10% HT-EGR. The results indicated that LT-EGR had a longer combustion duration compared with HT-EGR. When BMEP was 1.0 MPa, CA50 of HT-EGR advanced about 5oCA. However, CA50 of LT-EGR could still keep steady and in appropriate range, which guaranteed good combustion efficiency. Besides, LT-EGR had lower exhaust gas temperature, which could help to suppress knock. And its lower exhaust gas temperature could reduce heat loss.
2017-10-08
Technical Paper
2017-01-2242
Boyuan Wang, Zhi Wang, Changpeng Liu, Fubai Li, Yingdi Wang, Yunliang Qi, Xin He, Jianxin Wang
Abstract A new ignition method named Flame Accelerated Ignition (FAI) is proposed in this paper. The FAI system composes of a spark plug and a flame acceleration tunnel with annular obstacles inside. The FAI was experimentally investigated on a rapid compression machine (RCM) with optical accessibility and a single-cylinder heavy duty research engine. In RCM, the flame is significantly accelerated and the combustion process is evidently enhanced by FAI. The ignition delay and the combustion duration are both sharply decreased compared with conventional spark ignition (CSI) case. According to the optical diagnostics, the flame rushes out of the exit of the flame acceleration tunnel at maximum axial speed over 40 m/s, which exceeds 10 times that of CSI flame propagation. In radial direction, the flame curls outwards near the tunnel exit and keeps growing afterwards.
2017-10-08
Technical Paper
2017-01-2241
Xin Yu, Vincent Costanzo, Elana Chapman, Richard Davis
Abstract In this work, an experimental and analysis methodology was developed to evaluate the preignition propensity of fuels and engine operating conditions in an SI engine. A heated glow plug was introduced into the combustion chamber to induce early propagating flames. As the temperature of the glowplug varied, both the fraction of cycles experiencing these early flames and the phasing of this combustion in the engine cycle varied. A statistical methodology for assigning a single-value to this complex behavior was developed and found to have very good repeatability. The effects of engine operating conditions and fuels were evaluated using this methodology. While this study is not directly studying the so-called stochastic preignition or low-speed preignition problem, it studies one aspect of that problem in a very controlled manner.
2017-10-08
Technical Paper
2017-01-2238
Ripudaman Singh, Travis Burch, George Lavoie, Margaret Wooldridge, Mohammad Fatouraie
Abstract Numerous studies have demonstrated the benefits of ethanol in increasing the thermal efficiency of gasoline-fueled spark ignition engines via the higher enthalpy of vaporization and higher knock resistance of ethanol compared with gasoline. This study expands on previous work by considering a split fuel injection strategy with a boosted direct injection spark ignition engine fueled with E0 (100% by volume reference grade gasoline; with research octane number = 91 and motor octane number = 83), E100 (100% by volume anhydrous ethanol), and various splash-blends of the two fuels. Experiments were performed using a production 3-cylinder Ford Ecoboost engine where two cylinders were de-activated to create a single-cylinder engine with a displacement of 0.33 L. The engine was operated over a range of loads with boosted intake manifold absolute pressure (MAP) from 1 bar to 1.5 bar.
2017-10-08
Technical Paper
2017-01-2245
Xianlin Ouyang, Ho Teng, Xiaochun zeng, Xuwei Luo, Tingjun Hu, Xianlong Huang, Jiankun Luo, Yongli Zhou
Abstract In order to better understand how the Atkinson cycle and the Miller cycle influence the fuel consumption at different engine speeds and loads, an investigation was conducted to compare influences of early intake valve closing (EIVC) and late intake valve closing (LIVC) on the fuel consumption of a 1.5L turbo-charged gasoline direct injection (TGDI) engine. The engine was tested with three different intake cams, covering three intake durations: 251 degCA (the base engine), 196 degCA (the Miller engine), and 274 degCA (the Atkinson engine). Compression ratios are 9.5:1 for the base engine and 11.4:1 for the Atkinson and Miller engines, achieved with piston modifications. Results of this investigation will be reported in three papers focusing respectively on characteristics of the engine friction, in-cylinder charge motions for different intake events, and combustion and fuel economy without and with EGR for the naturally aspirated mode and boost mode.
Viewing 211 to 240 of 110718