| Cars as a transport greatly facilitates people’s life and work, with the continuous development of the automobile, the number of cars increasing year by year. Large Numbers of cars brought the economic development at the same time also brought such as environmental pollution, energy crisis and greenhouse effect and so on a.In order to change this situation, the car companies had already started the research and development of new energy vehicles, include the recent most rapid development of electric vehicles, hybrid electric vehicle,and the fuel cell vehicle which is called as the ultimate goal of future development by car makers, etc. The compressed air as a kind of clean energy which is widely used in many indoor machine and small hand tools, etc. But the compressed air in the development for the car power is a bit slow, so this topic research a new energy vehicles powered by compressed air.The piston structure of traditional automobile engine has stood the test of more than 100 years. Subject first determines the certain changes in the structure of the traditional internal combustion engine as the plan to research compressed air engine. So that it can reduce many workload. The first step of research is to understand the traditional internal combustion engine. By reading the data to find the common ground of internal combustion engine and pneumatic motor,and exploit them, and design the structure of innovation to complete the modification.After the previous research, finally determine the only need to increase a set of valve mechanism on a four-stroke engine, again connected to the storage tank to finish a modification of the air-powered engine. In this paper, sliding type of compressed air engine guiding valve mechanism was designed, it can be realized through a channel of air-powered engine intake and exhaust function.Compressed air was stored at the pressure of 20 MPa. First the compressed air through reduced pressure relief devices, then through the guiding valve mechanism into pneumatic motor. After the completion of the modified the experiment prove that the design of sliding type of compressed air engine guiding valve mechanism can drive the engine rotation.To optimize the design and improve the work performance of the air-powered engine, a series of detailed experiments was carried out on a two stroke air-powered engine. First determine the best of the engine air intake on the advance angle of 10 ° CA. On this basis, a verification experiment was carried out in the first place, in cylinder pressure curve obtained from test to prove the sliding type of compressed air engine guiding valve mechanism work well.In order to facilitate the research of the efficiency of compressed air of air-powered engine in different working conditions, different with gas phase and compression ratio, a new index was proposed to evaluate performance of theair-powered engine—the ratio of the mean effective pressure and the average pressure in the engine cylinder. Using steel, aluminum and nylon as three different kinds of material, the same size of the air distribution sliding block were made for the test. Experimental result shows that the weight of the air distribution sliding block has influence on the performance of the air-powered engine. Three pieces of air distribution sliding block whose intake duration angle are 128 °, 143 ° and 156 ° were used for the test. Experimental result shows that increasing intake duration angle can improve the expansion efficiency of the compressed air. A test was carried out under the condition of three different compression ratio. Experimental result shows that when we refit the air-powered engine based on the traditional gasoline engine and increase engine compression ratio, the expansion efficiency of the compressed air may be reduced. |
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