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Now weight reduction is increasingly needed in automotive industry to improve fuel efficiency and to reduce emission. Various lightweight technologies have been used to vehicles. Because of its heavy weight and complex shape, IP carrier tends to be integration and weight intensive. Therefore lightweight is necessary for IP carrier. This paper lists the fourth lightweight technologies used for IP carrier by now, which are Magnesium alloy part, Aluminum alloy part, Hybrid composite part, Composite material injection part. For magnesium alloy part and aluminum alloy part, they have been mass produced for some years. The hybrid composite part has been researched for some years. Recently, the injection composite part has been researched and some parts have been developed and tested. By outlining the design, manufacturing, weight reduction and cost of these lightweight technologies, this paper fully analyzed these used technologies.

This paper investigates the influences of EGR and Miller cycle on NOx emission of a heavy-duty two-stroke diesel engine. The NOx emission is strictly restricted by the IMO Tier III Emission Regulations, resulting in an insufficient application of the single emission reduction technology to meet the emission requirements. It is asserted that EGR is the most effective manner to reduce NOx emission, but the fuel consumption increases simultaneously. In consideration of emission reduction with fuel economy, EGR and Miller cycle were combined and studied in this paper. Parameters like in-cylinder pressure, in-cylinder temperature, mass in the chamber, emission (NOx and soot) and fuel consumption rate were investigated based on a single-cylinder 3D model. The wet condition that happens in the engine application was considered in the model development process. The model was validated and compared with the experimental data.

The level of boost pressure has a significant effect on optimizing the steady-state and transient performance of turbocharged diesel engines. However the problem of matching the wide speed range diesel engine and the high pressure turbocharging system has to be resolved. The regulated two-stage (RTS) system is an effective method to improve the fuel economy, transient response and smoke emissions. Compared with the difficult matching problem of the RTS system, the problem of boost pressure control is more complex due to the frequently changing operating conditions. To overcome the limitations of an open-loop control strategy, a closed-loop boost pressure control strategy was studied numerically using a mean value model of a diesel engine with RTS system. The system identification was conducted for the transient response from the turbine bypass opening command to the boost pressure.

The concept of regulated two-stage turbocharging system is proposed to provide high boost pressure level over a wide range of engine speed by regulating the energy distribution of two turbochargers. However, the control strategy of turbine bypass valve becomes more complicated due to the frequently changing working of vehicle diesel engines. In this paper, a two-stage turbocharging system was matched for D6114 diesel engine to improve the low-speed torque. The effect of valve opening on the steady-state and transient performance was analyzed, and two different regulating laws were determined according to the different optimum aims. Then the transient response characteristics of two different regulating laws were studied and optimized at three speeds with the transient loading test. For steady-state performance, the output power and fuel efficiency were increased with the matched turbocharging system.

Based on the principle of carbon footprint, this paper selects typical passenger cars, such as internal combustion engine vehicles (ICEV), plug-in hybrid electric vehicles (PHEV) and battery electric vehicles (BEV) in the market of China as the research objects, and compares the energy consumption and carbon emissions of the three vehicle models in the whole life cycle for three major stages of manufacturing, driving and recycling in three representative cities. The results show that the manufacturing energy consumption of BEV is 5 times of HEV and 10 times of ICEV. For the BEV, only after driving a certain mileage it can be a less the unit energy consumption and emissions than ICEV. The whole life cycle carbon emissions of passenger cars with different power types is not only related to mileage, but also related to the energy structure of local electric power supply.