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Dual-Clutch-Transmission (DCT) is one kind new automatic transmission which has double clutch structure. The most important unit of DCT is Transmission-Control-Module (TCM).In the development process of TCM, simulation is an important research tools. We have analyzed the DCT principle of work, established its mathematical model, created the charge and discharge oil models of typical wet dual clutch transmission, established the control logic to unify and separate double clutch in turn, and also designed out the shift control using fuzzy control using MATLAB/Simulink software. Utilizing engine model, driver model, the DCT model, the TCM model, the vehicle model, established the vehicle simulation model, and implemented simulation; Result indicated that, the established model can correctly reflect the torque and speed change when shifted gears and can correctly realize the automatic shift gears.

Material creep action under the high temperature is a important factor which should be considered analyzing the pin boss durability. This paper studied the plastic action of the pin boss under the thermomechanical load. As a result, the plastic strain range is smaller than Besides, pin boss damage may be derived from the bigger silicon particle concentration and the bigger iron debris concentration. The enlarged particle deformation under the severe load would cause microfracture between the silicon particles and the aluminum-silicon phase until the part broken.

In order to meet the Euro IV HD diesel engine emission standard legislation limits, an efficient SCR system is adopted for PM optimized YC6L350-40 HD diesel engine serving in China. This paper presents tests made on the engine. The engine had base NOx emission of 8.8g/kwh over the ESC and 8.7g/kwh over the ETC. Outfitted with a 24.7 liter 300cpsi SCR catalyst, the engine NOx emission dropped to 3.2g/kwh over the ESC and 3.5g/kwh over the ETC.

Coolant flow and its heat transfer directly affect the cooling efficiency, thermal load of heated components as well as thermal efficiency of diesel engine. An efficient approach to study cooling system for diesel engine is 3D CFD calculation for coolant jacket and 1D cooling system simulation. The velocity, pressure and heat transfer coefficients (HTC) distribution in the coolant jacket of a 4 cylinder diesel engine are computed by 3D CFD approach using AVL/FIRE software. The improved schemes can be put forward according to calculating results. The boundary condition of 1D cooling system for diesel engine can be obtained by averaging computed inlet and outlet total pressure drop and heat transfer coefficients from CFD calculation. The parameters of the engine, which are fitted with the vehicle such as capacity of radiator, fan and water pump, could be decided.

On-road testing of driving performance of the urban bus was carried out, and a representative urban bus driving cycle was developed after on-road testing, according to the test results. Then, the vehicle simulation software AVL CRUISE was used to simulate the dynamic behavior of the urban bus. It involves the simulation of complete drive train system and the driver behavior. The model is validated by comparing the results of the simulation to the results of the field test. Then the developed driving cycle is evaluated by fuel consumption resulted from the simulation and engine bench test on fuel economy.

This paper reports on the approach followed for the TCS verification of the payload AMS-02 (Alpha Magnetic Spectrometer), aiming at the qualification of the entire system, in steps, for the space environment. AMS-02 is a state-of-the-art experiment composed by a stack of seven different particle detectors, each of them having its own electronics and control equipments. It will be installed on the International Space Station Starboard segment S3 of the main Truss, and will be a 6500 kg payload, with a power consumption of 2000 W. The verification philosophy is driven by the need to qualify the flight hardware and by the necessary confirmation and correlation of the thermal mathematical models, based on experimental data. The hardware used on AMS-02 is derived from the state-of-the-art ground based detectors for high energy physics, hence not yet proven for operations in vacuum and in extreme thermal environment.

An LHP-based thermal control system for cryocoolers on the Alpha Magnetic Spectrometer (AMS-02) has been designed and analyzed by means of the system level model based on Sinda/Fluint. It is integrated with the International Space Station (ISS) model by means of a time-varying sink temperature definition, and the performance of LHP-based thermal control is investigated. A parametric analysis is carried out also to understand the influence of critical parameters on the operation of LHP.

In this paper, a diesel particulate filter system which uses needle felt as filtering medium to collect diesel particulates has been developed and tested in practical operation of the urban bus. The system includes a bag filter, an exhaust cooler, and a control unit. It was installed under the chassis of a YZL 6730C diesel bus, which operates in a loop route mostly with heavy load. The bus has covered more than 5,000km, during which there was no failure of the filter system to cause bus abnormal operation. It needs to be cleaned for about 50km, and the collected particulate matter has to be discharged for every 1200km. It can operate reliably and easily with very high collection efficiency. The collected particulate matter is analyzed by GC (Gas Chromatography)/MS (Mass Spectrometer), it is found that the collected particulate matter contains many poisonous and carcinogen substances and the filter is also effective to collect some of the SOF.

A calculation model for high-speed electromagnet property of electronic-controlled fuel injection system of diesel engine has been formulated with considering of leakage of magnetic flux and resistance of core. The results have been proved by relational tests. The results of an M490F type high-speed electromagnet show that in order to acquire good controlling effect, the resistance of core should not be ignored except it is much bigger than the solenoid resistance.

A new type of dual fuel supply system has been developed. This system is able to economically convert conventional diesel engines into dual-fuel engines like LPG/Diesel engines and CNG/Diesel engines, which are capable of either using single diesel fuel or using dual-fuel including both diesel and CNG fuel or both diesel and LPG fuel. These diesel-LPG engines have been applied to the diesel buses in the public transportation of Guangzhou city, one of the biggest cities in China, owning to their low soot emissions, excellent operating performances and extremely low cost as well. Compared with the diesel baseline engine, it was found that there were a significant reduction in soot emission and an improvement of the fuel consumption with the diesel-LPG engine. Also the strategy on LPG content is discussed in order to meet the demands for soot emission, fuel economy, transient performance and output power at the same time.