内部声激励对汽车减阻降噪的研究

减小汽车行驶中的空气阻力，抑制行驶时的气动噪声具有十分重要的意义。汽车车身模型风洞实验表明，用内部声激励可获得有效的减阻效果，而且还能起到抑制气动噪声的效果。实验得出声激励的频率、强度、位置等参数与减阻率的关系，以及有、无声激励时模型表面压力系数分布情况，还得到了声激励对气动噪声频谱特性影响的有关规律。

Investigation on Reducing Drag and Noise of an Automobile by Internal Acoustic Excitation

It is very important to reduce the aerodynamic drag and noise for a transport vehicle. A wind tunnel test for a model of the automobile body shows that beneficial effects on reducing drag and suppressing aerodynamic noise by using internal acoustic excitation. The relations among the parameters, such as acoustic frequency intensity, location and rates of drag reduction have been gotten, and pressure coefficient of the surface of the model with and without acoustic excitation are derived.The related relations of the influence of the acoustic excitation on the frequency-spectrum characteristic of the aerodynamic noise are given.