低速风洞的消声降噪改造设计研究

对搬迁改造中的西北工业大学低（变）湍流度风洞进行了降噪设计研究。根据低速风洞噪声的机理及频率特性和该风洞的结构形式及风扇转速,采用两种降噪方法——主动降噪和被动降噪,对风洞进行降噪设计。主动降噪设计方法包括风扇动力段的气动、结构及振动的声学优化设计,被动降噪设计则采用在风洞洞体上安装微穿孔板,利用共振吸声技术进行降噪。结果表明：结合上述措施,55m/s风速下,相同测点和相同运行条件下,风洞噪声值下降约30%;76m/s最大设计风速下,风洞环境噪声被控制在78dB以下。

An investigation of noise-elimination method for a low-speed wind tunnel

Some noise reduction technologies have been investigated at low-speed low（variable）-turbulence wind tunnel of Northwestern Polytechnical University.Based on the noise mechanism and frequency characteristics of low speed wind tunnel,both active and passive noise control technologies have been used to reduce the noise of the wind tunnel with a consideration of its structures and fan rotation speed.The active noise control technologies include acoustic optimization design of aerodynamics,structure and vibration of the fan power section.The micro-perforated panels are used on the wall of the wind tunnel to achieve resonant sound absorbing as a passive noise control technology.The investigation indicated that the noise,which measured under same wind conditions and same locations,was reduced about 30% at 55m/s wind speed and was kept as low as 78dB at 76m/s maximum wind speed.