Cudworth A L, Hanson W J, Vuisting W
Am Ind Hyg Assoc J. 1978 Nov;39(11):904-13. doi: 10.1080/0002889778507882.
Sixty-five commercial pneumatic mufflers in the size range of 1/8 to 3/8-inch American Standard Taper Pipe Thread (NPT) were evaluated for noise level as a function of air supply pressure and back pressure. Also, typical directivity pattern and spectral content were determined. A rating system has been devised, as well as individual prediction formulas, to rank order the mufflers and provide a capability of calculating expected noise levels for a given supply pressure. As this study reveals, noise reductions in excess of 40 dBA may be achieved by employing an efficient pneumatic muffler.
对65个尺寸范围为1/8至3/8英寸美国标准锥管螺纹（NPT）的商用气动消声器进行了评估，以研究其噪声水平与供气压力和背压的关系。此外，还测定了典型的指向性图案和频谱内容。已设计出一种评级系统以及各个预测公式，用于对消声器进行排名，并能够计算给定供气压力下的预期噪声水平。正如本研究所示，采用高效的气动消声器可实现超过40 dBA的降噪效果。
