用曲轴箱增压改善单缸四冲程柴油机性能研究

针对单缸四冲程柴油机保有量大，应用范围广，而又普遍存在油耗、排污相对偏高的问题，结合单缸四冲程柴油机工作原理及结构特点，在X195柴油机空气滤清器、进气管和曲轴箱之间增设一个带单向阀片的节能增压装置，利用曲轴箱内容积的变化(靠活塞的工作反面泵气)，把进入空气滤清器的清洁气体和从气缸内漏入曲轴箱内的气体一齐压入气缸，使发动机的充气效率得到提高，漏入曲轴箱内的可燃气体再次利用，从而达到降低油耗，减少排放污染的目的。增设的节能增压装置安装方便、结构简单、工作可靠、制造成本低、不需要单独设置驱动机构。X195柴油机安装节能增压装置前、后的性能对比试验，在云南金马柴油机总厂发动机试验室按照国标、部标的规定进行。实验证明，在不消耗原机功率，不改变原机任何结构的前提下，安装节能增压装置的发动机提高了功率，降低了油耗，减少了排放污染，该节能增压装置对改善单缸四冲程柴油机的性能是行之有效的。

Improving the performance of single cylinder four-stroke diesels with crankcase supercharging

The four-stroke diesel engines with single-cylinders are widely possessed and used in China. However, there are problems of high fuel consumption and exhaust emission. A fuel-saving and supercharging device with a single-direction valve mounted on X-195 diesel engine between the intake manifold and crankcase was developed. When the piston is moving down, unburnt combustion gases that leak into the crankcase are pressed, and then are drawn into the combustion chamber together with fresh air that comes from the air cleaner. The air-fuel mixture in the crankcase can be reused so as to reduce the exhaust emission and enhance the charging efficiency. This device has characteristics of simple construction, reliability, low cost, convenient to mount and does not interfere with the mechanical driving arrangement. The experimental results show that it can effectively not only increase the engine output power, but also reduce its fuel consumption and emission.