柴油机空蚀破坏因素的研究

Study on Factors Causing Cavitation Erosion of Diesel Engine

采用磁致振荡空蚀试验仪,进行振动幅度,振动频率,液体介质温度及成份,金属表面粗糙度等五种因素对空蚀破坏影响的试验研究。得出:空蚀破坏强度和振动幅度的平方成正比关系;降低金属表面粗糙度可以显著减小空蚀破坏;减小振动频率,改变液体介质温度,减小液体腐蚀性都可以较大幅度地减少空蚀破坏。本文详细讨论分析了试验结果,认为电化学腐蚀在空蚀破坏中起了一定的作用,并提出减小柴油机空蚀破坏的几点措施。其中减小镀铬缸套表面粗糙度措施已得到广泛实际运用,取得好的实用效果。

Tests and study were carried out to find out the effect of the 5 factors of vibration amplitude, vibration frequency, temperture and composition of liquid medium as well as metal surface roughness on cavitation erosion of diesel engine, using magnetosriction cavitation erosion test instrument. It is concluded from these tests that the intensity of cavitation erosion is directly proportional to the square of vibration amplitude; the reduction of metal surface roughness may remarkably decrease cavitation erosion: and decreasing vibration frequency, changing liquid medium temperature and reducing liquid corrosivity can all greatly alleviate cavitation erosion. By analysing test results in detail, the author of this paper holds that electrochemical corrosion plays a certain role in causing cavitation erosion and puts forward several measures for decreasing diesel engine cavitation erosion. Reducing the surface roughness of chromalized cylinder jacket as one of the measures has been widely applied to practice with satisfactory practical results.