怠速工况下燃油系统的噪声评价和改善*

在实车怠速工况下的噪声振动性能评价过程中,燃油系统是发动机诸多子系统当中一个重要的声源。针对这一子系统产生的车内脉动噪声偏大的问题,总结出了对燃油类液体的脉动噪声振动控制机理、原因及诊断方法。首先,采用在燃油轨内追加阻尼器的方案很好地抑制了谐频噪声;然后,从燃油泵这一主要激振源出发,提出了设定燃油泵单品噪声振动、声品质等目标值的策略,即从源头上控制关键产品的噪声性能。在此基础之上,与之相应的解决方案实施之后,怠速工况下的车内噪声提升到了较好的水平,而且,燃油系统噪声的主观评价结论也认为得到了明显改善。

The noise evaluation and improvement of fuel system at idling

During of the noise and vibration evaluation on actual vehicle, especially at idling condition, the fuel system is also the one of most important sound source within many sub-systems of engine. In order to solve the problems of pulsation noise and low frequency noise generated in this subsystem, the mechanism and control method of noise and vibration for the hydraulic kinds such as fuel had been summarized. Through diagnosing and analyzing with details on various relevant structure components of the fuel system, including the influence of common rail damper on pulsation noise, vibration isolation between fuel tank and vehicle body, control strategy of fuel pump noise and the layout of the fuel filter, then the diagnostic measurement, noise source identification, transmission path, structural vibration response and other targeted analysis were carried out one by one. Based on above these, the interior vehicle noise at idling condition had been upgraded to a better level after the implementation of the corresponding solutions. Moreover, the subjective evaluation conclusion on the fuel system noise was also considered to be improved obviously.