采用声学测量装置在半消声实验室风洞中评价了不同入口气流速度和角度条件下换热器的声学特性.结果表明,空调换热器产生的噪声是低流速状态下多腔体耦合共振的结果,而且具有宽频特性.换热器中气流速度的方向和大小对其噪声的影响很大:换热器的气动噪声随着气体流速增加而增大,而小于7m/s的气流不会产生噪声;过大或过小的入口气流角度都不会产生气动噪声.噪声频率随着气体流速增加而呈现出线性增长,给定的换热器存在一个恒定的斯特雷哈尔数。
The behaviors of noise through the heat exchanger of indoor unit at a low-speed free stream were studied by aero-acoustic performance measurements in a semi-anechoic chamber with different velocities and angles. The experimental results indicate that the noise can be generated at particular velocity and an- gles which are considered as the most important factor that influences the aerodynamic performance of the heat exchanger. With the increasing in the flow velocity, the frequency of noise increases linearly, and there exists a fixed Strouhal number for the given heat exchanger.