基于FE-SEA模型的整车气动噪声分析

Analysis of Aerodynamic Noise of Vehicles Based on FE-SEA Model

以某款SUV车型为研究对象,将采用计算流体力学(Computational Fluid Dynamics,CFD)和声扰动方程(Acoustic Perturbation Equations,APE)获取的侧窗表面脉动压力作为激励,基于混合有限元-统计能量分析法(Finite Element-Statistical Energy Analysis,FE-SEA)提出一种全新的整车中频段气动噪声预测模型,通过阻抗管吸声系数试验逆推得到声学包材料参数,结合传递损失试验和基于声功率的降噪水平试验(Power Based Noise Reduction,PBNR)对整车混合模型进行调校对标,保证噪声传递路径的准确性。基于该模型,加载外流场对流和声学激励进行中频段气动噪声仿真,并将分析结果与气动噪声试验进行对比,验证该方法的可靠性。研究表明,在车型开发概念设计阶段采用基于声扰动方程与混合有限元-统计能量分析相结合的方法能有效精确预测气动噪声,为后续整车气动噪声性能的优化提升做铺垫。

Taking an SUV vehicle as the research object,its pulsating pressure on the side window surface is obtained by using computational fluid dynamics(CFD)and acoustic perturbation equation(APE).With the use of the pulsating pressure as the excitation,a full new method based on hybrid finite element-statistical energy analysis(FE-SEA)for aerodynamic noise prediction of the whole vehicle in the mid-frequency band is proposed.The material parameters of the acoustic package are obtained through the inverse test of the sound absorption coefficient of the impedance tube,and the hybrid model of the whole vehicle is adjusted by combining the transmission loss test and the sound power-based noise reduction test(PBNR)so as to ensure the accuracy of the noise transmission path.Based on the model,the mid-frequency aerodynamic noise simulation is carried out with the external flow field convection and acoustic excitation,and the analysis results are compared with those of the aerodynamic noise test to verify the reliability of the method.Compared with the other methods,this method can more accurately calculate the structure-borne sound transfer in the mid-frequency range,thereby greatly improving the accuracy of acoustic simulation.The research shows that the method based on the combination of acoustic disturbance equation and hybrid finite element-statistical energy analysis in the conceptual design stage of vehicle development can be effectively used in aerodynamic noise prediction,paving the way for the subsequent optimization and improvement of vehicle aerodynamic noise performance.