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At present, about 40% of the fuel energy is discharged into air with the exhaust gas when an automobile is working, which is a big waste of energy. A thermoelectric generator (TEG) has the ability to harvest the waste heat energy in the exhaust gas. The traditional TEG cold-end is cooled by the engine cooling system, and although its structure is compact, the TEG weight and the space occupied are important factors restricting its application. In this paper, under the premise of ensuring the TEG maximum net output power and reducing the TEG water consumption as much as possible, the optimization of the TEG water thickness in the normal direction of the cold-end surface (WTNCS) is studied, which results in lighter weight, less space occupied and better automobile fuel economy. First, the thermal characteristics of the target diesel vehicle exhaust gas are evaluated based on the experimental data. Then, according to the thermoelectric generation model and the cold-end heat transfer model, the effect of the WTNCS on the cold-end temperature control stability and the system flow resistance are studied. The results show that the WTNCS influences the TEG cold-end temperature. When the engine works in a stable condition, the cold-end temperature decreases with the decrease of the WTNCS. The optimal value of the WTNCS is 0.02 m and the TEG water consumption is 8.8 L. Comparin it with the traditional vehicle exhaust TEG structure, the power generation increased slightly, but the water consumption decreased by about 39.5%, which can save fuel at0.18 L/h when the vehicle works at the speed of 60 km/h.

When the vehicle parks in the hot environment, the temperature inside the cabin would increase substantially, and has a bad impact on the comfort of occupants. Ventilation is an effective cooling means in hot environment and the current method applied in vehicle is apt to open ventilation system transitorily when the car starts, reaching the pre-cooling purpose. However, the working hours of ventilation are limited due to great energy consumption, thus in this research solar power is taken into consideration. In this study, a newly exhaust fan is installed at the rear of the car, combining with the original car cabin blower as ventilation system to improve cooling efficiency. The newly installed fan and the original car cabin blower were driven by the solar power panels. Firstly, the influence of blower flow rate on the cooling effect was studied. Then the influence of the cabin air pressure drop on the cooling effect was evaluated. Finally, optimal power allocation between original cabin blower and newly installed exhaust fan was studied when considering cooling effect and total power consumption. Results based on a car model indicates that, optimal power allocation could be achieved when air circulation flow was about 25 L/s, on which condition temperature difference between inside and outside of passenger compartment could be controlled within 6°C, and temperature inside the cabin could be reduced by 16.

Regenerative braking used in hybrid electric vehicle can recover energy while braking, which can improve the driving distance of electric vehicle. As commercial vehicles trend to large tonnage, the power of vehicle retarding is greater than the power of vehicle driving. It is hard to ensure that braking stability of the automotive only relies on regenerative braking, which influences traffic safety. This research combines regenerative brake and eddy current retarder. It can extend retarding time by sharing the brake torque of eddy current retarder using the regenerative brake. Meanwhile the regenerative brake supplies electric power for eddy current retarder and it will improve the energy efficiency of system. This paper aimed at target type vehicle that is 8 ton new energy commercial vehicles, and established the regenerative brake model and eddy current retarder model, and then combined vehicle running conditions for the system simulation. The simulations revealed that combined auxiliary brake has steady performance under each working condition and meet torque demands of auxiliary brake as well as obviously extend retarding time of traditional eddy current retarder. This system achieves the closed loop of energy and is both compact-sized and energy-saving.

Sweeping Vehicle is an important tool to beautify the city environment with the characteristics of low cruise speed, less driving power consumption, and small operating area, which provides a good application prospect for the development of the electric sweeping vehicle. The characteristics of excellent stability at low speed, efficient energy conversion, convenient operability, and environment-friendly make it the first choice for cleaning road surface. In the study, the structure of vacuum dust collection system without sweeping brush is adopted in the designed electric sweeping vehicle. What is more, no dust particles generate when a sweeping vehicle is dumping. Therefore, it is worthy of the name "clean" vehicle. Firstly, electromotor and exhaust fan model is established, the joint performance between working electromotor and exhaust fan and the electromotor efficiency features are analyzed. Combining with the driving speed, it is analyzed that the suction and subsidence system's influence on the effect of dust collection. Taking into account coupling of the dust control system and the working state of the vehicle, vacuum dust control structure is designed, the dust removal efficiency is analyzed and the simulation is conducted. Finally, the dust-free dumping is realized. The result shows that, comparing traditional sweeping vehicle, electric sweeping vehicle system energy consumption is reduced by about 50%, noise is lowered significantly, direct emissions don't exist, and working time can meet the demand of regional cleaning.

The driveline system of the heavy truck is usually composed of clutch, transmission, transfer case, drive shaft, etc. A fluid torque converter could be equipped in front of the transmission in order to improve the starting performance. Also, a hydraulic retarder could be introduced for auxiliary braking so as to adapt the truck to the brake on the long downgrade in mountainous regions. Thus, the driveline heat load would have a notable increase. Both the fluid torque converter and the hydraulic retarder would produce a large quantity of heat, and a special cooling system is needed to lower the transmission fluid temperature. The driveline heat load is often calculated based on empirical formula. However, for the heavy truck, if the heat value is underestimated, driveline components would suffer from overheated damage. On the contrary, if the heat value is overestimated, it will lead to the oversize radiator and affect the underhood arrangement. In this paper, we focus in the heavy truck with the gross vehicle weight of 80,000 kg, which is equipped with the fluid torque converter and the hydraulic retarder. The driveline model is built based on AMESim. The heat load of each primary heating component is calculated referring to the existing driving cycle and combining with the actual driving condition of the truck. On these bases, the parameters and the layout of cooling devices (such as the oil cooler) could be set for the heavy truck working properly in different driving conditions.