家用电器风机噪声的一种等效声源建模方法

风机噪声是油烟机、吸尘器、电吹风等家用电器的主要噪声源，噪声管理是这类产品开发的关键。为缩短家用电器的开发周期，需要在设计阶段对产品进行噪声预测与评估。传统预测方法是对风机和系统整体建模，进行气动噪声流体-声学联合仿真(Computational Fluid Dynamics-Computational Aeroacoustics, CFD-CAA)。但该方法使声源与声传播过程相耦合，设计每当有修改的时候，就要需要进行全系统计算，开发效率较低。为此，文章提出一种可以将风机声源特性与系统声传播过程解耦的噪声源建模方法，分析风机气动声源特性，建立风机等效源模型。设计了风机噪声试验，测试风机的风口噪声，提取等效声源强度，用于快速预测不同系统、不同工况的噪声。将该模型应用于两种型号的油烟机噪声分析，结果表明，对不同的风道结构，系统噪声预测误差均在3 dB左右。

An equivalent modeling method for household electric fan noise

Fan noise is the main noise source of range hood, vacuum cleaner, hair dryer and other household appliances. Noise management is the key to the development of such products. In order to shorten development cycle of the products, noise prediction should be carried out in the design stage. The traditional method is to model the fan and the system as a whole, and use the computational fluid dynamics-computational aeroacoustics (CFD-CAA) method to calculate aerodynamic noise. However, this method couples the acoustic source to the sound propagation process. Whenever there is a modification in the design, the whole system needs to be calculated, so the development efficiency is low. Therefore, an acoustic source modeling method which can decouple the acoustic source characteristics from the sound propagation process in the system is proposed. By analyzing the characteristics of the fan aerodynamic noise, the fan equivalent source model is established. To quickly predict the noises of different systems in different working conditions, the tuyere noise of the fan is tested and the equivalent source strength is extracted. This model is applied to the noise analysis of two types of range hoods. The results show that the prediction error of system noise is about 3 dB for different air-duct structures.