风冷热泵机组出风口噪声的治理

酒吧热泵机组风机通风量大，运行时产生高分贝、宽频的噪声。而且酒吧附近敏感点多，要在有限空间达到良好降噪效果具有相当难度。目前，国内多采用阻性或单节阻性-抗性消声器来治理出风口噪声，但治理效果不理想。结合工程实例，通过频谱分析及扩张消声理论，采用不同长度不同扩张比的三节扩张室串联(取代单节扩张室)，结合阻性消声器，在有限空间内设计一种新型阻抗复合消声器，使热泵出风口噪声降低18 dB（A）左右。此消声器设计简单，经济合理，技术先进可靠，占用空间小，有较高的实用价值。

Noise Control at the Vents of Heat Pump Units of Bars

The fans of heat pump units in the bars have large ventilation flux. Operation of the pump units will generatestrong noise with high dB value and wide frequency band. In addition, there are lots of sensitive points around the bars, so itis difficult to achieve a good effect of noise reduction in such a limited space. At present, the dissipative or single resistancedissipativemufflers are usually used to control the air-vent noise in our country, but the results are not ideal. In this paper,based on spectrum analysis and expansion muffler theory, using the three- expansion chambers with different length anddifferent expansion ratio in series （instead of single expansion chamber）, and combining with the dissipative muffler, a newtype of dissipative-resistance muffler is designed in a limited space, which makes the air-outlet noise of the heat pump unitsto be reduced by nearly 18 dB （A）. This muffler is not only simple, economic, reliable and advanced, but also space saving.Thus, it has important significance in engineering application.