Abstract:

The fans of heat pump units in the bars have big-air quantity. Strong noise with high dB value and wide frequency band is generated while the units are running. Except that, there are lots of sensitive points around the bars, so it’s difficult to achieve a good effect of noise reduction in a limited space. At present, most of projects make use of dissipative or single resistance - dissipative muffler to control the air-outlet noise in our country, but the results are not ideal. Combining with the engineering example, spectrum analysis and expansion muffler theory, putting three expansion chambers with different length and different expansion ratio in series (instead of single expansion chamber), and also using the dissipative muffler, a new type of dissipative - resistance muffler was designed in a limited space, which makes the air-outlet noise of heat pump units be reduced by about 18dB (A). This muffler is not only simple, economical, reliable and advanced, but also save space, so it has high practical value.

摘要：

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。

关键词: 声学, 风冷热泵机组, 设计, 消声器, 扩张室