Research On Air Powered Vehicle Engine

As people's increasing demands for environmental protection and sustainable development in the 21st century, the environment-friendly clean vehicle is called for to replace the combustion one which exhausts the irreproducible mineral resources and even worse, heavily pollutes the air.Without using any mineral fuel, the air-powered engine(APE), which outputs the mechanical energy transformed from the compressed air energy into the torque form, is of completely zero emission. Funded by the Natural Science of Foundation of China-Ford Fund- "Research on air powered vehicle engine" (No.50122115) and the National 10th Five Years Plan Special Research Programs of China-"Research on Compressed Air Powered Vehicle" (No.2003BA408B14), the application of APE in the clean vehicle field is aimed in this project; the working principles of the APE and features of the energy release of compressed air are discussed; guided by systematic theory analysis and adequate experiments, the mathematic models of one-stage and two-stage expansion APE are innovated and improved; several engines are developed; then bench and whole-vehicle tests are proceeded; their working features under different structures and parameters are profoundly analyzed. All these provide the air-powered engine's optimization and further application with strong theoretical base and experiment data, which will be both theoretically and practically important in the further research work.The research work is divided into the following chapters:Chapter 1: The cause and significance of the project are introduced. Different kinds of clean autos are listed and their feasibility is discussed. Finally, the history of the clean autos' research and their current research state nationally and internationally are summarized; the main research objects are proposed for this dissertation.Chapter 2: The working principles of APE and the energy emission features of the compressed air are analyzed with the claim that, the essential way to improve the efficiency is to improve the exchange conditions for expansion process in the cylinders. The structure of APE is discussed, and referring to the air-powered motor and performance demands for the vehicle, the reciprocate structure with good sealing preferment, high efficiency, large torque output, low and stable speed is found to be an appropriate choice to meet the working needs. Applying the theories of thermodynamics and mechanics, the working process of basicAPE--single-stage expansion, is analyzed and its related mathematicmodel is built up. The simulation methods based on this model are discussed, which is the preparation for the later research work.Chapter 3: The working characteristics of the single-stage expansion engine are researched on by the simulation. Then, the influences on the engine brought by the parameters as speed, port timing, inlet air pressure and the volume and stroke-bore ratio of the cylinder are comprehensively analyzed, and the performance rules under the parameters above are obtained through the process.Chapter 4: Based on the research work in Chapter II, the mathematic model of two-stage expansion APE is established and its working characteristics are summarized. The influences on the engine's performance brought by parameters like speed, port timing, inlet air pressure, two-stage bore ratio, heat-exchange and ambient temperature are comprehensively analyzed. Finally, the performing difference between the single-stage and two-stage expansion APE are compared and analyzed elaborately.Chapter 5: The proto single-stage expansion APE is designed and produced. The comprehensive APE test bench is built. When engines are experimented on the bench, the research on integrating tech of air-powered vehicle is carried out simultaneously. Then the new engine and itscomplementary air-supply system are integrated onto the vehicle successfully. Finally, the road experiment of the first nationwide air-powered vehicle is accomplished.Chapter 6: the research work is summarized and perspectives on the...