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Trucks parked at idle create excessive fuel consumption and exhaust emissions. One of the solutions to this issue is to institute a separate power system, the APU. It will be in operation when vehicle is parked and engine is off to provide the electricity and support the necessary needs (refrigerator, air conditioning, TV, etc.). This paper offers the insight of development of an Electrical Power Cell (EPC) as the candidate of the APU. The device consists of a unique Opposed Piston and Opposed Cylinder (opoc) engine and a high speed rotary generator. An extensive investigation has been conducted during the engine development program to create a special unniflow scavenging process of this two stroke engine. As the result, it realizes zero fresh charge loss with high scavenging efficiency. This paper provides the technical challenges and solutions in achieving the design targets.

A free piston internal combustion engine coupled with a linear generator is proposed for hybrid vehicle application. The engine works on CI two-stroke cycle with direct fuel injection. Uniflow was chosen for an efficient scavenge process. The exhaust valve timing and lift are to be dynamically controlled by electromechanical driven poppet valves, developed by FEV. A numerical simulation model of the proposed engine has been generated in this paper. The piston dynamics, cylinder scavenge process, combustion process, and friction characteristics are coupled together for systematic analysis with the code. It is meant to be a tool for prediction and optimization of the engine design and control parameters, such as fuel injection timing, valve/port timing, and electric power output. The analysis results are discussed in this paper.

The dual-throat jet technique has been successfully used to improve cold-starting of the swirl-type IDI diesel engines. It has been proven that, with the aid of the second throat connecting the swirl chamber and the main combustion chamber, the cold-starting process was more stable, quiete and clean. However, the understanding of the mechanism of this technique is far less than satisfied as regarding to the better control and further development. An intensive fundamental experimental investigation of the transient process of the ignition and combustion at cold-staring had been conducted on a swirl-chamber IDI diesel engine with the help of high-speed photography. Based on the results of this investigation, the following conclusions have been approached: 1) There exist three types of heat release rate pattern at the cold-starting.

A comparison study on the commonly used solution schemes of one-dimensional gas flow in IC engine manifolds, i.e. the method of characteristics and the finite difference schemes, was conducted in this paper. The study was based on computer simulations of the flow in a typical pipe-volume configuration under both steady and unsteady boundary conditions. The simulation results indicate that all the solution schemes offered fairly good accuracy in parallel pipes under steady flow conditions. However, under unsteady flow conditions, especially in tapered pipes commonly used in IC engine manifolds, all the existing solution schemes encountered difficulties. These included such aspects as the mass and energy conservation, non-physical overshoot, solution stability and physical process distortion. The solution schemes were compared based on the case calculations and the related problems are specified.