Total Cylinder Volume And Combustion Chamber Volume

The automobile compression ratio refers to the ratio of the total volume of the cylinder to the volume of the combustion chamber. It indicates the degree to which the gas in the cylinder is compressed when the piston moves from bottom dead center to top dead center. Compression ratio is an important parameter to measure the performance index of automobile engine. Generally speaking, the compression ratio of the engine is greater; at the end of the compression stroke, the pressure and temperature of the mixture are higher, and the combustion speed is faster. Therefore, the greater the engine power, the better the economy. However, when the compression ratio is too large, not only the combustion situation cannot be further improved, but abnormal combustion phenomena such as deflagration and surface ignition will occur, which in turn affects the performance of the engine. In addition, the increase in engine compression ratio is also restricted by exhaust pollution regulations.