增压器引起的车内哨声产生机理及控制研究

Investigation on Generating Mechanism and Controlling of Vehicle Inner Whistler Noise from Engine Turbocharger

针对搭载涡轮增压汽油机的某车型在急加速(tip-in)时车内产生的哨声异响进行了测试与分析,确定了异响是由增压器的同步噪声引起,因此根据同步噪声产生的原因对转子系统的动平衡进行优化,优化后同步噪声改善明显;但是,又出现了次同步噪声,同样在车内造成口哨声,然后对此次同步噪声的产生机理进行分析,并提出了一种在增压器浮动轴承内表面加槽的方案对次同步噪声进行控制,最后对改善方案进行了试验验证,试验表明采取上述措施后,车内口哨声消除。

In this paper, a vehicle with a turbocharged gasoline engine was measured and analyzed because of whistle noise inside the vehicle during a tip-in process. The test results show that the whistle noise inside vehicle is caused by synchronous noise due to unbalance of the rotor system and the synchronous noise disappears by controlling the unbalance of rotor. However, the sub-synchronous noise caused by oil film whirling during bearing clearance is obvious. Then the generating mechanism of sub-synchronous noise is researched so as to resolve the problem fundamentally. A scenario that installing circular oil grooves in the inner bearing wall is proposed to reduce sub-synchronous noise and the test result shows that interior whistle noise had disappeared.