汽车空调压缩机噪声异常问题的诊断与试验

某国产轿车存在空调开启时车内噪声较大及怠速时车内出现间歇性异常噪声问题,为寻找振源,对样车及其压缩机系统进行了试验诊断与分析,包括样车摸底试验、压缩机安装状态的刚体模态试验、压缩机在消声室中的台架试验等,最终确定压缩机噪声较大原因为空调管路制冷剂冲击导致的管路振动噪声向车内的直接传递,间歇性异常噪声原因为压缩机工作频率与发动机8阶工作频率的拍频。根据诊断结果,提出了相应的改进措施,并进行了改进后样车的试验验证,结果表明改进效果比较明显。

Abnormal Noise Diagnosis and Test of Air Conditioning Compressor in Automobiles

In order to find the reasons of the big noise and intermittent abnormal noise inside of a car when the air conditioning is on, the test diagnosis and analysis of the air conditioning systems and whole car are completed. The tests include a baseline test of the whole car, a modal test of the compressor, and a bench test of the compressor in the anechoic room. The results indicate that the big noise is generated by the vibration shocked by refrigerating fluid which final passes inside of the car, and intermittent abnormal noise is generated from the vibration of the compressor beating at working frequency and the 8th order vibration of the engine. According to the diagnostic results, two improved methods are proposed and verified with tests.