汽车空调出风管道气动噪声分析与控制

通过耦合CFD(Computational Fluid Dynamics)与专业声学代码SYSNOISE求解汽车空调管道气动噪声,即利用LES(Large Eddy Simulation)湍流模型对空调管道的瞬态流场进行求解获得噪声源项,然后将噪声源项作为边界条件导入SYSNOISE来计算噪声的传播.根据流场分析与声场分析结果对空调管道的结构提出了两种改型方案,并对改型前后的空调系统噪声进行了测试.测试结果表明相比原始空调系统,两种方案都能有效降低噪声且方案二效果更好,驾驶员附近的噪声最大降幅达4.5 dB.

Numerical Analysis and Control of the Aerodynamic Noise of Automotive HVAC Duct

The aerodynamic noise of automotive HVAC duct was predicted with computational fluid dynamics(CFD) coupled with specialized acoustics codes SYSNOISE, i.e., the transient flow field in the automotive HVAC duct was computed on the basis of large eddy simulation(LES) and the noise source term was obtained. Then the noise source term was imported into the acoustic software called SYSNOISE as the boundary condition to compute the spread of noise. According to the analysis result of flow field and acoustic field, tow improvement schemes were proposed, and air-conditioning system noise was tested on the basis of prototype and improvement model. The test results have shown that the tow schemes are effective in reducing the air-conditioning system compared with the prototype model. In particular, the noise is significantly reduced near the driver's ear, and the largest declines by up to 4.5 dB.