车内低频振动噪声的虚拟传递路径分析

传递路径分析法是诊断汽车振动噪声问题准确有效的方法。试验传递路径分析耗时耗力且需要实制样车,为在整车开发初期诊断汽车振动噪声问题,对整车虚拟传递路径分析法进行了研究。首先建立了包含底盘的整车声固耦合有限元模型,采用频率响应法预测车内声学振动响应,发现驾驶员右耳声压在38 Hz处以及驾驶员座椅导轨振动在59 Hz处存在较大峰值。在有限元模型基础上建立了整车虚拟传递路径分析模型,该模型合成的声学振动结果与频率响应法结果吻合较好,验证了模型的正确性。利用虚拟传递路径法对两处峰值作诊断分析,根据分析结果对贡献量大的路径进行优化。优化结果表明,38 Hz处驾驶员右耳声压降低2 dB,59 Hz处座椅振动改善效果明显。

Virtual Transfer Path Analysis of Vehicle Interior Noise and Vibration in Low Frequency

Transfer path analysis(TPA)is an accurate and effective method to diagnose vehicle vibration and noise of automobile.The test TPA is time-consuming and labor-intensive and requires a prototype car,in order to diagnose the vehicle vibration and noise problems in the initial stage of vehicle development,the virtual TPA method is studied.Firstly,a vehicle structure-acoustic coupling finite element model with chassis is developed and the frequency response method is used to predict the acoustic vibration response in the vehicle.It is found that there exist peak values at 38 Hz of the sound pressure of the driver's right ear and at 59 Hz of the vibration of the guide rail of the driver's seat.The virtual TPA model based on the finite element model is developed.The results of acoustic vibration reconstructed by the model are consistent with that of frequency response method,which verifies the correctness of the model.The two peak values are diagnosed with virtual TPA method and the dominant paths are optimized according to the analysis results.The optimization results show that the sound pressure of driver's right ear at 38 Hz is reduced by 2 dB,and the seat vibration at 59 Hz is improved obviously.