柴油机漏气量试验研究

Experimental Study on Blow-By of Diesel Engine

针对某车用6缸增压中冷柴油机,开展了不同发动机转速、扭矩、机油温度和最高燃烧压力工况下的漏气量试验研究。试验结果表明,发动机的转速和扭矩是影响漏气量的主要因素,而机油温度和缸内最高燃烧压力对漏气量的影响较小。相同扭矩下,随转速增加,漏气量基本呈线性增加趋势,转速每增加10%,漏气量约增加12%;相同转速下,随扭矩增加,漏气量也基本呈线性增加趋势,扭矩每增加10%,漏气量约增加5%。漏气量最大的工况并不是漏气率最高的工况,漏气率比较高的区域出现在中等转速和中等扭矩交汇的区域。

The blow-by tests were carried out on a 6-cylinder turbocharged and intercooled diesel engine under the operating conditions of different engine speeds,torques,oil temperatures and maximum combustion pressures.The test results showed that engine speed and torque were the main influencing factors and oil temperature and maximum combustion pressure had little influence on blow-by.The blow-by generally showed a linear increase trend with the increase of engine speed under the same torque condition.The blow-by increased approximately 12%with every 10%increase of speed.The blow-by also showed a linear increase trend with the increase of engine torque under the same speed condition.The blow-by increased approximately 5%with every 10%increase of torque.The condition of largest blow-by did not agree that of peak gas leakage rate.The relatively high leakage rate occurred at the intersection of medium speed and medium torque.