密封间隙对汽车冷却水泵性能影响的研究

摘要

For vehicle engine cooling pumps,to investigate the widely existed performance decline,even failure under high-load operating conditions,the CFD simulation is adopted to investigate the effects of the seal gap size on the pump performance.Com-pletely sealed,Gap size 0.2 mm,0.3mm,no seal,four different sealing conditions are investigated respectively.The results show that,with seal failure,the pump performance is dropped to 60% of the design performance.While even with 0.2mm gap,the pump performance is decreased by 10%.Considering that the cooling pump is always operating under vibration environment,and it is difficult for the commonly used mechanical seal to guarantee safety.Subsequently,a canned cooling pump structure is proposed, and is investigated preliminarily.%为探明汽车发动机冷却泵在高负荷运转条件下，普遍存在的性能指标急速下滑，甚至失效的问题，采用 CFD数值计算，研究冷却泵密封间隙大小对泵性能参数的影响。分别计算了完全密封、密封间隙分别为0．2mm，0．3mm 及无密封条件下的外特性参数，并作了分析对比。计算结果表明，在密封完全失效的条件下，泵指标只能达到设计指标的60％，而在0．2mm 间隙下，性能指标也已下降10％。考虑到冷却泵始终处于振动环境中运行，而通常的端面密封很难长时间保持有效。因此，提出一种屏蔽式的冷却泵，并初步进行了研究。