Proceedings of SAE-China Congress 2016: Selected Papers

Inhaltsverzeichnis

1. Frontmatter

2. Chapter 1. Effect of Compression Ratio on the Combustion Characteristics of Premixed Charge Induced Ignition for Diesel Engine

   Yujie Guo, Jianjun Zhu, Zhiwei Su, Wei Han, Zilong Wu

   Abstract

   In order to explore the combustion performance of premixed charge induced ignition for dual fuel engine, an experiment was undertaken on CY25TQ diesel engine to investigate the combustion and emission characteristics by changing the compression ratio. Experimental results show that under the condition of 1200 r/min, when the compression ratio is reduced from 16.9 to 15.4, and the premixed charge induced ignition leading to the start of combustion reaches the maximum delay to 1.5°CA ATDC, the biggest drops of maximum pressure, maximum pressure rise rate and peak of instantaneous heat release rate reach 52, 47 and 29% respectively. But the effective thermal efficiency declines 24%.

3. Chapter 2. Study of the Effect of Combustion Chamber Shapes on the Mixture Formation and Combustion Characteristic on CNG-DI Engine

   Tao Jiang, Xuedong Lin, Miao Yang

   Abstract

   A combustion system model of CNG-DI engine which was modified from a 2.0 L diesel engine was built with software FIRE, the turbulence combustion model of CNG-DI engine was verified with the experimental result of CNG-DI optical engine, on the condition of unchanged 4 valves structure of original engine and the jet location, the spark plug was arranged between the two exhaust valves, the effect of different combustion chamber shapes on the microscopic physical fields such as turbulence characteristic in cylinder was simulated and studied, based on which the effect of combustion chamber shapes on the formation and combustion of mixture and the formation rule of NO was researched. The result shows that he combustion shape has a tremendous influence on the turbulence characteristic of cylinder and distribution characteristics of concentration fields especially besides the spark plug, which plays a decisive role on the whole process of combustion; Not only the production of NO can be inhibited and the combustion propagation speed which is in favour of lean burn can be controlled effectively when the straight mouth combustion chamber was used at the bottom of which has a proper embossment. The amount of NO is closely related to the size of the reaction area and the duration of reaction besides the reaction rate of NO when the CNG fuel is injected into cylinder directly and burned thin, which can be controlled by the rational design of the structure of combustion chamber.

4. Chapter 3. Damage Risk Evaluation and Optimization for BIWS Spots-Weld

   Daolin Deng, Yu Zhang, Zhonghao Xu

   Abstract

   A spots damage risk evaluation method was proposed based on the spots axial and shears force. The spots damage risk index for a SUV BIW was calculated and evaluated, and the BIWs spots were optimized. The evaluation results show that most of the positions with high risk spots are the same with the damaged spots of the road or bench test. The spots damage problem was solved by optimizing the spots based on risk index. This method can achieve the spots damage risk evaluation and optimization efficiently.

5. Chapter 4. Fatigue Durability Analysis of a Frame Based on Multi Body Dynamics

   Qin Zhang, Fengchong Lan, Jiqing Chen, Qinsheng Huang

   Abstract

   A fatigue analysis procedure for a frame based on virtual prototype and multi-body dynamics is established. The first 5 modes frequencies of the finite element model are calculated and verified by experimental test. The frame model is turned into a flexible body. A rigid flexible coupling model is established with suspensions, tires and the flexible frame body. The dynamic response of the model is analyzed in class D road at a uniform motion, the load-time histories of the connected locations are extracted; The S-N curve of material is fitted through the tensile strength limit; combined with the stress distribution of unique load, the dangerous positions and theirs fatigue life are predicted. The result shows that the frame damage hotspots are mainly distributed in the bracket connected with the body, frequency domain energy of connected location load is within 18Hz, the minimum fatigue life mileage is km. The result has a guiding significance for the research of the fatigue durability of vehicle frame.

6. Chapter 5. Study on Calibration of Secondary Air Injection System in a V12 Engine

   Hongzhi Zhao, Wei Wang, Xiaofan Zhong

   Abstract

   The emission regulation of CHINA 6 is going to be issued, the limits of the emissions will be greatly strict. The utilization of secondary air injection system is proved to be one of the effective methods to reduce the CO and THC emissions in the phase of cold engine. The application of secondary air system in the process of the V12 engine developing, the control strategy, the result of calibration and the diagnostic calibration are introduced, according to the development experience. It’s a reference to the engineers who face the similar issue.

7. Chapter 6. Research on Soot Filtration and Pressure Drop Characteristics of DPF

   Ying Gao, Hongqi Liu, Wei Chen, Tieqiang Fu, Maodong Fang, Jun Li

   Abstract

   An integrated DPF filtration model is proposed to study the properties of soot filtration and pressure drop, which includes deep bed filtration model, cake filtration model and pressure drop model. Research results show that the evolution of filtration can be divided into two stages named as deep bed filtration and cake filtration respectively. During deep bed filtration, soot is trapped in the filter wall, which results a rapid pressure drop gradient of 7.6 Pa/s. However, the soot quality only accounts for 1.6% of the total in whole filtration process. Compact soot layer is developed during soot filtration. And a linear increase of pressure drop with the gradient of 1.4 Pa/s during the stage. Besides, the pressure drop caused by the soot layer and cake layer are 54 and 38% respectively in the whole simulation duration.

8. Chapter 7. Research on the Present Situation and Factors of Volatile Organic Compounds in Car Cabin

   Jiabao Ren, Shujie Xu, Xuefeng Liu, Wei Liu, Enyou Cui

   Abstract

   This article analyzed cabin indoor VOCs emission of more than 400 vehicles in attainment rate, average concentration and distribution situation. Result showed that in the past two years, the average concentrations of VOCs in vehicle decreased, but the overall compliance rate was still not high, acetaldehyde becoming limiting factor of overall compliance level. Meanwhile, this paper studies the relationship between sampling time, temperature, seasonal factors and VOCs detection results. The results provide a basis for the revision of the vehicle VOCs testing standards and manufacturing enterprise can use it to predict VOCs detection results.

9. Chapter 8. Optimization Method of Low Exhaust Temperature Emissions of City Buses Meet China V

   Tengteng Li, Changyuan Wang, Kongjian Qin, Xiaojun Jing

   Abstract

   Emission problem of city bus running under low speed and low load is gradually becoming a research hotspot. The city buses were taken as research object in this paper. Emissions of two city bus were tested on heavy duty chassis dynamometer under CCBC. Test results showed that under low speed and low load conditions, because of low transformation efficiency of SCR, NOx emission of engine was serious, but the NOx emission of test vehicle can be significantly reduced by using the method of fixing heat insulating material on the exhaust pipe and ECU calibration according to low speed and load conditions of city buses. Test results also showed that after rehabilitation, emission reduction effect of NOx was above 40%, other emissions do not deteriorate significantly.

10. Chapter 9. Analysis and Test Research for Three-Phase Short-Circuit of Permanent Magnet Synchronous Motor for an Electric Vehicle

    Sibo Wang, Chao Lu, Xiaoxu Wang, Huichao Zhao

    Abstract

    Permanent magnet synchronous motor (PMSM) is widely used in the electric vehicle as a drive motor. For specific application requirements of the electric vehicle motor system, there are new faults and application characteristics in motor system’s three-phase short-circuit. Based on the \( dq \) axis coordinate system mathematical model of PMSM, this paper derives the \( dq \) axis current transient equations of three-phase transient short-circuit with load or without load in initial state. Combined electric vehicle PMSM operating characteristics, based on the typical working conditions, this paper analyzes the influences of motor demagnetization risk in different conditions by comparing the transient current changing process simulation results of different initial transient \( dq \) axis currents. Then according to the characteristics of the three-phase transient short-circuit, designs and builds a test platform, and verifies the correctness of the analysis and mathematical simulation models by testing. It provides an important theoretical analysis and test verification methods for analyzing the electric vehicle PMSM three-phase short-current function and determining the risk of demagnetization.

11. Chapter 10. Based on an Improved Sliding Mode Observer for Position Estimation of PMSM

    Su Zhou, Daxiang Zhu, Zhe Hu

    Abstract

    To reduce the chattering problem resulted from signum function in conventional sliding mode observer (SMO), a sensorless speed controller based on an improved SMO is proposed for permanent magnet synchronous motor (PMSM), where signum function is substituted for sigmoid function and the stability of the proposed SMO is verified using the Lyapunov method, the influence of different tilt parameters on position estimation is analyzed as well. To reduce phase delay in position estimation in conventional SMO, a new observer which has the structure of an extended Kalman filter is designed for back electromotive force estimation, which is expected to decrease estimation error of improved SMO. Based on improved SMO position sensorless control is modeled in MATLAB/SIMULINK, and result of simulation demonstrates correctness of improved SMO.

12. Chapter 11. Simulation Analysis and Research of C70GB Fuel Cell Vehicle

    Ping Chen, Chen Liang, Jiangqiu Li, Hongliang Jiang

    Abstract

    Due to long endurance mileage and short fueling time, fuel cell vehicle had became the main development direction of range extend electric vehicle. In order to improve the service life and tech-characteristics, many departments carried out research related to the fuel cell and control system of fuel cell vehicle. In this study, the power systems, fuel cell systems, power battery systems and other simulation systems were constructed and tested for C70GB model, and calculate the power, energy consumption and other aspects of the calculation. The simulation results show that the fuel cell can effectively improve the energy power battery vehicle system dynamic and climbing performance, equipped with two 70 MPa cylinders can effectively extend the mileage of the vehicle, and ensure daily using demand.

13. Chapter 12. Electrochemical-Thermal Coupled Model of Lithium-Ion Batteries for Low Temperature Charging

    Peng Wu, Jan Romberg, Hao Ge, Yakun Zhang, Jianbo Zhang

    Abstract

    To study the low temperature charging performance of lithium-ion batteries, the electrochemical-thermal coupled model is developed. Some key parameters in the model are measured, which includes the kinetic related parameters and the thermal properties. The model is validated with the charging curves at different temperatures with two thermal boundary conditions and several C-rates. Using this model, the voltage loss during low temperature charging is broken down to electrolyte voltage loss, electrode interfacial kinetic loss and solid particle concentration polarization loss. Results show that the negative electrode intercalation kinetic loss is the dominant during low temperature charging.

14. Chapter 13. Research on Low Frequency Torque Ripple of In-wheel Motor of Four Wheel Independent Drive

    Zhe Li, Zheng Ling, Yue Ren, Yinong Li, Ke Wang, Zhenfei Zhan

    Abstract

    In-wheel motor is a key power element for four wheel independent drive electric vehicle. It can supply accurate driving force control and achieve energy saving in electric power vehicle. Switched Reluctance (SR) motor has become an ideal candidate due to high output torque and reliable performance. However, huge output torque ripple in operation, which affects the comfort and handling stability of electric vehicle, limits its application in vehicle. In this paper, some factors behind low frequency noise and torque ripple of SR motor are investigated from a view of energy consumption including magnetic flux path pattern in SR motor and current imbalance. Furthermore, phase current balance control strategies to improve output torque ripple in operation are proposed. Results show that low frequency noise and torque ripple can be eliminated by applying the proposed current balance control strategy. It provides a good design method for SR motor to achieve excellent comfort and handling performance in four wheel independent drive vehicle.

15. Chapter 14. Relaxed Static Stability for All-Wheel-Drive Electric Vehicle Based on Yaw Moment Control

    Jun Ni, Jibin Hu

    Abstract

    All-wheel-drive electric vehicles have been widely focused, which provides the possibility for advanced control technology. In this chapter, a novel control theory for automobile will be proposed-Relaxed Static Stability (RSS), which could also lead to new overall configuration concept. The basic idea of RSS is that the lateral dynamic system of the vehicle could be designed inherent static unstable (oversteer) to improve overall configuration flexibility, and be closed-looped stable based on pole assignment with external yaw moment provided by the independent motors. In this chapter, the basic schematic control strategy of RSS is described. Finally, a nonlinear dynamic model is used to verify the performance of RSS control. The results show that the handling performance of the vehicle could be significantly improved and adjusted to satisfy different handling demand based on adjusting desired pole locations.

16. Chapter 15. Test Study on Characteristics of Multi-Hole Injector for Gasoline Direct Injection Engine

    Jujiang Liu, Hong Chen, Sicong Lin, Yuhuai Li, Lin Ye, Shuang Zhang

    Abstract

    By means of High speed camera and CCD camera, combining with high energy laser device, spray characteristics test of multi-hole injector for gasoline direct injection engine have been done on the constant volume chamber bench. The variation laws of spray penetration, spray angle and spray target were studied under different injection pressures, different injection pulses and different injection background pressures. Also the variation tendency for spray penetration of different injector flow ranges have been tested and analyzed. The results indicate that injecting pressure boosting can strengthen the initial penetration developing of spray plume, fuel atomizing becoming better, resulting in increasing of spray angle. The effects of changing background pressure on spray angle and target are not obvious. And spray target coordinate is mainly determined by the injector hole layout. Under the same injection pressure and flow quantity, injector having the larger flow range has shorter penetration than that of smaller flow range.

17. Chapter 16. Integrated Exhaust Manifold Type Cylinder Head Structure Design for Gravity Casting Process

    Ming Chen, Wenlei Yang, Tianyu Zhang, Donghang Liu, Hanqing Song

    Abstract

    This chapter aimed at the problem of casting defects during the trial manufacture of a certain engine cylinder head. Combined with the structural characteristics of the internal integrated exhaust manifold, the structure design optimization of gravity casting process introduced in detail. Through the process simulation analysis and trail production verification and other means, reaching the production scrap rate control objectives.

18. Chapter 17. Experimental Research on Macroscopic and Microscopic Characteristics of Ethanol-Fatty Acid Methyl Ester Blends Sprays

    Junge Li, Xiaocao Yu, Bin Liu, Tiegang Hu, Xibin Wang

    Abstract

    Spray characteristics of Ethanol-Fatty Acid Methyl Ester Blends under common-rail injection condition were experimental investigated, by the high speed photography and particle/droplet image analyses (PDIA). The results show that spray cone angle and project area is increased with the increase of ethanol percentage and ambient pressure. Sauter mean diameter (SMD) increases with the increased axial distance at the same radial distance. SMD sharply decreases with the increased injection pressure, the average amplitude is 2 μm. SMD of Fatty acid methyl ester (FAME) decreases about 3 μm after mixing ethanol. Spray characteristics of Ethanol-Fatty Acid Methyl Ester Blends and diesel are similar, thus the engine is rarely modified while fueled with FAME/Ethanol blends.