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2017-10-08
Technical Paper
2017-01-2271
Zhongshu Wang, Mingyang Shao, Ming Li, Dan Wang, Zhongchang Liu
For diesel/natural gas dual fuel engine, the combustion of pilot diesel plays an important role to the following mixture combustion process. To better understand the effects of multiple injections, a detailed study was conducted on a 6-cylinder turbocharged intercooler diesel/natural gas dual fuel heavy-duty engine at low to mid-range loads. Multiple variables were tested, including single injection timings, multiple injections timings and mass ratios, natural gas percentage of energy substitution, engine speeds and loads. The investigated results show that pilot diesel multiple injections have an obviously effect on not only pilot diesel combustion process but also natural gas mixture combustion process. Early injection leads to pilot diesel ignition mode differs from traditional diesel engine compression ignition mode in the sense that it does not occur at a specific place in the spray, which is a two-stage auto ignition mode.
2017-10-08
Technical Paper
2017-01-2207
Nobunori okui
Next-generation vehicles which include Electric Vehicles, Hybrid Electric Vehicles and Plug-in Hybrid Electric Vehicles are researched and expected to reduce CO2 emission in the future. In order to reduce the emissions of the heavy-duty diesel plug-in hybrid vehicles (PHEV), it is necessary to provide the high exhaust-gas temperature and to keep the aftertreatment system effective. The engine starting condition of PHEV is cold, and the engine start and stop is repeated. And, the engine load of the PHEV is assisted by the electric motor. Therefore, the aftertreatment system of PHEV is not able to get the enough high exhaust-gas temperature. And, the warm-up of the exhaust-gas aftertreatment system for PHEV is spent the long time. So, it is worried about a bad effect on the emission characteristics of PHEV. In this study, we focused on the electrical heating catalyst system (EHC), which is one of the next generation electrical technologies. This test PHEV was equipped with EHC.
2017-10-08
Technical Paper
2017-01-2201
Zhongye Cao, Tianyou Wang, Kai Sun, Lei Cui
In uniflow scavenged two-stroke marine diesel engines, the main function of scavenging process is to replace the burned gas with fresh charge. It is integral to the subsequent combustion process, thereby affecting the engine's fuel economy, power output and emission performance. In this paper, a complete working cycle of 6S35ME engine of MAN Diesel&Turbo was simulated by using the CFD software CONVERGE with full engine geometry including intake and exhaust ports. The simulation based on RANS and standard k-epsilon model was in good agreement with experiment. Based on the above calibrated model, the influence of exhaust valve closing (EVC) timing and swirl ratio on the scavenging process were investigated.
2017-10-08
Technical Paper
2017-01-2185
Chao He, Jiaqiang Li, Longqing Zhao, Yanyan Wang, Wei Gu
More and more stringent emission regulations and the desire to reduce fuel consumption lead to an increasing demand for precise and close-loop combustion control of diesel engines. Cylinder pressure-based combustion control is gradually used for diesel engines in order to enhance emission robustness and reduce fuel consumption. However, it increases the cost. In this paper, a new prediction method of combustion parameters including cylinder pressure is presented for diesel engines. The experiment was carried out on a engine test bench to obtain the ECU (Electronic Control Unit) signals of a heavy-duty diesel engine by calibration software. The combustion parameters is measured by a combustion analyzer, such cylinder pressure, combustion center of gravity (CA50) and the maximum combustion temperature (MCT). A combustion model using genetic programming (GP) is built.
2017-10-08
Technical Paper
2017-01-2197
Vignesh Pandian Muthuramalingam, Anders Karlsson
Owing to increased interest in blended fuels for automotive applications, a great deal of understanding is sought for the behavior of multicomponent fuel sprays. This sets a new requirement on spray model since the volatility of the fuel components in a blend can vary substantially. It calls for careful solution to implement the differential evaporation process concerning thermodynamic equilibrium while maintaining a robust solution. This work presents the Volvo Stochastic Blob and Bubble (VSB2) spray model for multicomponent fuels. A direct numerical method is used to calculate the evaporation of multicomponent fuel droplets. The multicomponent fuel model is implemented into OpenFoam CFD code and the case simulated is a constant volume combustion vessel. The CFD code is used to calculate liquid penetration length for surrogate diesel (n-dodecane)-gasoline (iso-octane) blend and the result is compared with experimental data.
2017-10-08
Technical Paper
2017-01-2440
MahendraMohan Rajagopal
Current developments in tractor transmission design has galloped to new heights with the introduction of CVT, Power shift, Power shuttle, hydrostatic etc besides the vastly available synchromesh and constant-mesh gearboxes. In contrary to the above existing facts of new powertrain development, there is a definite market need to revamp the heritage tractor models to be equipped with the modern transmission systems. This will help the customers have the advanced drivetrain features in these legacy tractors, that have won many hearts. One such modernization, was the development of new power shuttle transmission in legacy tractor models for TAFE tractors. Power shuttle primarily enables (a tractor in this case) to go forward and reverse by operating a wet clutch without human intervention. A flick of lever, usually on the steering column changes the direction of the tractor at the same speed of the gear selected.
2017-10-08
Technical Paper
2017-01-2438
MahendraMohan Rajagopal, Velmurugan M A
Recently, new and emerging technological developments in powertrain were mostly accompanied with electronics for efficient and precise control of powertrain system. Agricultural tractors are of no exception to this context. Most of the higher horsepower tractors above 50 HP are equipped with modern transmission systems such as Power-shuttle, Power-shift etc. having their wet clutch transmission and diesel engine controlled by an Electronic Control Unit. This is possible only with an engine that receives and provides electronic signals. Whereas a tractor with mechanical engine is of predominant use in the Indian farm lands due to their low cost and immediate availability compared to that of an engine equipped with hi-fi electronics. Hence, there is a demand for low cost powertrain with improved controls and without engine electronics.
2017-10-08
Technical Paper
2017-01-2227
Wei Guan, Vinícius Pedrozo, Hua Zhao, Zhibo Ban, Tiejian Lin
Abstract In order to meet increasingly stringent emissions standards and lower the fuel consumption, significant efforts are being made to develop high efficiency low emission internal combustion engines and after-treatment systems. In addition to the trade-off between thermal efficiency and nitrogen oxides (NOx) emissions, the conversion efficiency of the diesel aftertreatment system decreases rapidly at lower exhaust temperature, which occurs at low load operations. Thus, it is necessary to investigate and identify the appropriate combustion and engine control strategies which can lead to lower vehicle exhaust emission by keeping the engine-out NOx low and NOx aftertreament conversion efficiency high through elevated engine exhaust gas temperature (EGT). In this work, an experimental investigation has been performed using external EGR and Miller cycle achieved by delaying the intake valve closing (IVC) timing on a single cylinder heavy-duty diesel engine.
2017-10-08
Technical Paper
2017-01-2205
Velmurugan M A, MahendraMohan Rajagopal
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
2017-01-2221
Peixuan ZENG, Penghao ZHANG
Abstract:In low temperature condition, the increase of fuel viscosity, the decrease of flow-ability of lubricating oil and the decrease of storage battery performance cause the engine starting difficult. The current electrical heating method can improve the engine starting performance in low temperature condition, but it causes a negative influence on storage battery performance and exhaust emission. In this paper, a warming device uses solar energy to directly warm up the engine. The device transfers solar power into thermal energy and store it into heat reservoir and uses heat conductor to warm up the engine. By using solar power to save power, the lifespan of the engine is extended and exhaust emission is decreased. This paper find out the heat amount necessary for diesel engine through resource gathering and calculation, choose an appropriate device and design a corresponding solar warming system. Keywords: warming system, solar power, diesel engine
2017-10-08
Technical Paper
2017-01-2359
Yaodong Hu
Energy saving is becoming one of the most important issues for the next generation of commercial vehicles. The fuel consumption limits for commercial vehicles in China have stepped into the third stage, which is a great challenge for heavy duty commercial vehicles. Hybrid technology provides a promising method to solve this problem, of which the dual motor coaxial series parallel configuration is one of the best options. Compared with P2 configuration, the powertrain can not only operate in pure electric or parallel mode, but also can operate in series, which shows better flexibility. In this paper, regulations on test cycle, fuel consumption test methods and its limits of the third stage will be introduced and explained in detail. Then, the quasi static models of the coaxial series parallel powertrain with/without gearbox under C-WTVC cycle are built.
2017-10-08
Technical Paper
2017-01-2364
Jiaqiang Li, Chao He, Jianwei Tan, Zihang Peng, Zidi Li, Wei Chen, Shijie wang
Urea selective catalytic reduction is the most promising technique to reduce NOx emissions from heavy duty diesel engines. 32.5wt% aqueous urea solution is widely used as ammonia storage species for the urea selective catalytic reduction process. The thermolysis and hydrolysis of urea produces reducing agent ammonia and provides to catalysts to reduce NOx emissions to nitrogen and water. However, the application of urea SCR technology has many challenges at low temperature conditions, such as deposits formation in the exhaust pipe, lack deNOx performance at low temperature and freezing below -12℃. For preventing deposits formation, the aqueous urea solution is difficult to be injected into the exhaust gas stream at temperature below 200℃. The aqueous urea solution used as reducing agent precursor is the main obstacle for achieving high deNOx performances at low temperature conditions.
2017-10-08
Technical Paper
2017-01-2368
Wenji Song, Weiyong Tang, Bob Chen, Jiapeng zhang
The 4JB1 diesel engine originated from Isuzu has large share in the China light duty truck market. However, the tightened NOx emission target enforced by NS-V legislation compared with NS-IV regulatory standard is very challenging for this engine platform which originally adopted the DOC+POC catalyst layout. Furthermore, combustion characterization of this type engine leads to high soluble organic fration (SOF) content in engine out particulates, which requires the catalysts in the exhaust after-treatment system (ATS) to deliver high SOF conversion efficiency in order to meet the regulation limit for particulate matters (PM). In this paper, an innovative DOC+V-SCR exhaust catalyst layout with DOC+V-SCR is introduced. The front DOC is specially formulated with optimized PGM (Platinum Group Metal) loading which ensures effective SOF oxidation while keeping sulfuric acid and sulfate generation minimal.
2017-10-08
Technical Paper
2017-01-2383
Guoyang Wang, Jun Zhang, Bo Yang, Chuandong Li, Shi-Jin Shuai, Shi Yin, Meng Jian
Urea selective catalytic reduction (SCR) is a key technology for heavy-duty diesel engines to meet the increasingly stringent nitric oxides (NOx) emission limits of regulations. The urea water solution injection control is critical for urea SCR systems to achieve high NOx conversion efficiency while keeping the ammonia (NH3) slip at a required level. In general, an open loop control strategy is sufficient for SCR systems to satisfy Euro IV and Euro V NOx emission limits. However, for Euro VI emission regulation, advanced control strategy is essential for SCR systems due to its more tightened NOx emission limit and more severe test procedure compared to Euro IV and Euro V. This work proposed an approach to achieve model based closed loop control for SCR systems to meet the Euro VI NOx emission limits. A chemical kinetic model of the SCR catalyst was established and validated to estimate the ammonia storage in the SCR catalyst.
2017-10-08
Technical Paper
2017-01-2194
Mateusz Pucilowski, Sam Shamun, Mehdi Jangi, Martin Tuner, Xue-Song Bai
Experimental heavy-duty DICI methanol engine is studied under high compression ratio conditions (CR=27). The fuel is injected with common-rail injector close to the top-dead-center (TDC) position with three different injector pressures, leading to a spray formation causing a so called wall-wetting. Numerical simulations using RANS/LPT/WSR and PDF models are employed to investigate the local conditions of the injection and combustion process. The CFD results are compared with the pressure trace and emissions from the metal engine experiment. It is shown that the simulations captured the same trend of increased amount of unburned hydrocarbons at higher injection pressures. Moreover, the intake temperature adjustments were required to correctly capture the ignition delay time when WSR model was used, whereas with the PDF method such adjustments were not needed.
2017-10-08
Technical Paper
2017-01-2268
Zhanming Chen, Long Wang, Tiancong Zhang, Qimeng Duan, Bo Yang
Liquefied natural gas (LNG) fuelled engines have been widely equipped on heavy duty vehicles both for fuel-economic and environmental protection concerns, however, they always suffer from deteriorated combustion performance and flame stability due to relatively low burning velocity of methane for lean mixture. In this paper, experimental study was conducted on a turbo-charged, spark-ignition, lean-burn LNG engine with methanol port injection. The combustion characteristics such as cylinder pressure traces, heat release rate (HRR), mass fraction burned (MFB), ignition delay, centroid of heat release, position of CA50 and CA90, as well as cyclic variation of peak pressure were analysed under light load (BMEP=0.3876MPa) with different methanol substitution rates (MSR=0%, 5.2%, 10.2%, 17.2%). The experimental results show that combustion phase advanced with increment of MSR due to faster burning velocity of methanol.
2017-10-08
Technical Paper
2017-01-2350
Chalermwut Wongtaewan, Umaporn Wongjareonpanit, Komkrit Sivara, Ken Hashimoto, Yoichiro Nakamura
In Thailand, most heavy-duty trucks were equipped with diesel engine, while a small portion was equipped with compressed natural gas (CNG) engine. However, in the past few years the number of CNG fuel trucks in Thailand has increased significantly due to the cheaper cost of CNG. In general, the emphasis of heavy-duty diesel engine oil performance is on piston cleanliness and soot handling properties, while thermal and anti-oxidation properties are most critical for CNG engine oil performance. For truck fleet owners who operate both types of trucks, using the inappropriate oil that is not fit-for-purpose can adversely affect engine performance and reduce engine service lifespan under prolonged usage. A novel CNG/diesel engine oil has developed by PTT to meet both JASO DH-2 performance for heavy-duty diesel engine oils and OEM requirements for CNG engine oils.
2017-10-08
Technical Paper
2017-01-2393
E. Robert Fanick, Svitlana Kroll
Semi-volatile organic compounds (SVOC) are a group of compounds in engine exhaust that either form during combustion or are part of the fuel and lubricating oil. Since these compounds occur at very low concentrations in diesel engine exhaust, the methods for sampling, handling, and analyzing these compounds are critical to obtaining good results. As a result, a sampling method was validated using dilute exhaust for sampling and analyzing SVOCs in engine exhaust during transient engine operation. Trends for the comparison of volatile-, semi-volatile-, and particulate-phase SVOC were compared both with and without exhaust aftertreatment.
2017-10-08
Technical Paper
2017-01-2450
Chao Xu, Fuyuan Yang, Jinyu Zhang
Power-split is highlighted as the most popular concept for full hybrid electric vehicles (HEV). However, the energy management and design of power-split heavy duty truck under Chinese driving conditions still need to be investigated. In this paper, the parametric design and an equivalent consumption minimization strategy (ECMS) for the power-split heavy duty truck are presented. Besides, the influence of a penalty factor also discussed. Meanwhile, two different methods to search the engine operation point has been proposed. And the simulation shows both fuel consumption can satisfy the second phase fuel consumption standard and the third phase fuel consumption standard which will be implemented in 2020, in the C-WTVC (Chinese-World Transient Vehicle Cycle). Based on ECMS a design for generator motor and traction motor in power-split heavy duty truck has been processed. The fuel consumption has been indicted to decrease, with the motor power increasing.
2017-10-08
Technical Paper
2017-01-2462
Ruipeng Zhang, Kaichuang Meng
The powertrain of the separated axle hybrid electric dump truck was analyzed, and the vehicle dynamics model was established. Considering the switch among different drive modes during the process of driving, a driving force coordinated allocation control strategy was applied. The control strategy adopts hierarchical structure, the upper layer determines power take-off mode of the vehicle, the middle layer calculates the drive torque of each axle according to its axle load, the lower layer uses PID algorithm to avoid the slip of the drive axle. Control model is established according to the control strategy, combined with the established vehicle dynamic model, co-simulation was conducted. The simulation results show that the driving force coordinated control strategy can adapt to the full load climbing condition and low adhesion road condition, realize the reasonable distribution of driving force and make full use of the ground adhesion.
2017-10-08
Technical Paper
2017-01-2353
Bernardo Tormos, Leonardo Ramirez, Guillermo Miró, Tomás Pérez
Attending the oncoming licensing of API F4K oil category for Heavy duty Vehicles, which main objective is to embrace the opportunity to reduce fuel consumption and CO2 emissions lowering the High Temperature High Shear (HTHS) oil viscosity a fleet test was performed during 2016 in a fleet of urban buses in the city of Valencia. This paper describes the results of a comparison test where the effect of the use of API FA4 like engine oils are used to measure their fuel consumption benefits over the fleet. The aim was to verify and quantify the theoretical benefits in terms of fuel consumption in Heavy Duty applications. The study was performed using 48 urban buses which include diesel and CNG models of the city of Valencia. These buses were divided in two groups; a control and a test group, using regular oils and API FA4. The fuel consumption of buses was calculated with distance and refueling.
2017-10-08
Technical Paper
2017-01-2351
Bernardo Tormos, Guillermo Miró, Leonardo Ramirez, Tomás Pérez
Low viscosity engine lubricants (LVO) are considered a possible solution for improving fuel economy in ICE. So, the aim of this study was to verify experimentally the performance of low viscosity lubricants regarding engine wear, since the use of LVO could imply unwanted wear performance. Potential higher wear could result in a reduction in life cycle for the ICE, a non-desired effect. In addition, currently limited data are available regarding “real-world” performance of LVO in a real service fleet. In this particular case, there were included out-of-specifications oils in terms of HTHS dynamic viscosity, where low viscosity was considered (3.0 cP), making this test highly interesting for industry.
2017-10-08
Technical Paper
2017-01-2266
Bin Yang, Hu Wang, Mingfa Yao, Zunqing Zheng, Jialin Liu, Naifeng Ma, Qiping Wang, Haien zha, Peng Chen
Gasoline partially premixed combustion shows the potential to achieve clean and high efficiency combustion. Injection strategies show significant influence on in-cylinder air flow and in-cylinder concentration distribution before auto-ignition, which can significantly affect the combustion characteristics and emissions. This study explored the effects of various injection strategies, including port fuel injection (PFI), single direct injection (DI), double direct injection (DIP+DIM) and port fuel injection coupled with a direct injection (PFI+DIM) on the combustion characteristics and emissions on a modified single cylinder heavy duty diesel engine fueled with 92# gasoline. The results showed that CA5 and CA50 of DIP+DIM are more sensitive to injection timing than PFI+DIM and single direct injection strategy, partially due to the effects of DIP on mixture stratification and low temperature reaction of gasoline.
2017-10-08
Technical Paper
2017-01-2242
Boyuan Wang, Changpeng Liu, Zhi Wang, Li Fubai, Yingdi Wang, Yunliang Qi, Xin He, Jian-Xin Wang
A new ignition method is proposed called flame accelerated ignition, which is realized by a flame acceleration tunnel set between the spark plug and the main chamber with annular spoilers inside. The investigation of flame accelerated ignition was experimentally accomplished on both a rapid compression machine with optical accessibility and a single-cylinder heavy duty engine. In rapid compression machine study, synchronous pressure sensing and high-speed photography were used with spark ignition cases tested for comparison. The results show that the combustion process is significantly accelerated by flame acceleration ignition. The combustion duration is shortened by more than 30% under all loads compared with spark ignition. According to the optical results, the axial speed of flame outside the flame acceleration tunnel reaches at least 30 m/s and shows positive correlation with load, which is over 10 times than that of conventional flame propagation caused by spark ignition.
2017-09-23
Technical Paper
2017-01-1956
Jie Bai, Jie Tong, Libo Huang, Xin Bi, Haitao Jiang
Due to the particularity of the goods, the collision of dangerous goods transport vehicles such as tanker truck may lead to explosion, leakage and environmental pollution, causing great harm to society and the environment .This paper focuses on the effects of different loads (no load, half load, full load) on key parameters of autonomous emergency braking system for tanker truck. The autonomous emergency braking algorithm model is established according to the kinematic equation of the vehicle. And the autonomousemergency braking algorithm is simulated by PreScan and Simulink under different scenarios. After that, the simulation-optimized algorithm has been tested on a real vehicle. The influence of the tank load on the TTC triggering threshold of emergency braking and the braking distance is the focus of the simulation and the real vehicle test.
2017-09-19
Technical Paper
2017-01-2154
Alan Hiken
A review of critical technologies and manufacturing advances that have enabled the evolution of the composite fuselage is described. The author’s perspective on several development, military, and production programs that have influenced and affected the current state of commercial fuselage production is presented. The enabling technologies and current approaches being used for wide body aircraft fuselage fabrication and the potential reasons why are addressed. Some questions about the future of composite fuselage are posed based on the lessons learned from today and yesterday.
2017-09-17
Technical Paper
2017-01-2535
Yongbing Xu
The continuous braking of the brake drum will cause the brake thermal decay when the heavy truck is driving down the long slope in the mountain areas. This reduces the braking performance and the braking safety. The engine braking and the retarder braking both consume the kinetic energy of the truck and can assist the truck driving in the mountain areas. This research proposes a combined braking strategy of the heavy truck in the mountain areas based on the mountain GIS information and the former recorded information of the slope gradient. The accelerator pedal is released in the middle of the uphill to assist the engine braking and access the shift between the kinetic energy and the potential energy. Different braking methods are allocated properly according to the slope length and gradient in the downhill. The vehicle dynamic model is established to analyze the speed variation and the truck’s braking characteristics on the long slope.
2017-09-17
Technical Paper
2017-01-2500
Bo Huang, Longjie Xiao
Head-up Display (HUD) system can avoid divers’ distraction on dashboard and effectively reduce collisions caused by emergency events, which is gradually being realized by researchers around the world. However, the current HUD only displays information like speed, fuel consumption, other information like acceleration and braking can’t be displayed yet. This research will uses the color and position change of the indicator symbol to remind drivers of braking information like braking time, braking severity, which can alert drivers to make braking operations timely and accurately. The system has the advantages of safe, intuition and real-time. The vehicle safety speed is calculated according to the road parameters like adhesion coefficient, slope and curvature as well as vehicle parameters like vehicle mass and centroid. And then the appropriate braking operations like braking time are obtained by combining the vehicle status like speed and steering.
2017-09-17
Technical Paper
2017-01-2493
Sivakumar Palanivelu, Jeevan Patil, Ajit Kumar Jindal
Brake system represents an important aspect of the vehicle dynamics apart from being an active safety system. The vehicle retardation and stopping distance completely depend upon the performance of brake system and the functionality of all components. However, the performance prediction of the entire system is a challenging task especially for a complex configuration such as multi-axial vehicle applications. Furthermore, due to its complexity most often the performance prediction by some methods is limited to static condition. Hence, it is very important to have equivalent mathematical models to predict all performance parameters for a given configuration in all different conditions. This paper presents the adopted system modelling approach to model all the elements of the pneumatic brake system such as dual brake valve, relay valve, quick release valve, front and rear brake actuators, foundation brake etc.
2017-09-17
Technical Paper
2017-01-2508
Xianyao Ping, Jialiang Liu, Gangfeng Tan
Using friction brakes for long time can increase easily its temperature and lower vehicle brake performance in the downhill process. The drivers' hysteretic perception to future driving condition could mislead them to stop untimely the engine brake, and some other auxiliary braking devices are designed to increase the brake power for reduction of the friction brake torque. The decompression engine brake has complex structure and high cost, and the application of eddy current retarder or hydraulic retarder on the commercial vehicles is mainly limited to their cost and mass. In this paper, an innovative brake guidance system for commercial vehicles with coordinated friction brakes and engine brake is introduced to guide the drivers to minimize the use of the friction brakes on the downhill with consideration of future driving conditions, which is aimed at releasing the engine brake potential fully and controlling the friction brake temperature in safe range.
Viewing 1 to 30 of 7610