out of the pipeline meaning in English

管路外销售法

This paper studies the mechanism generated from flow - noise in seawater pipeline , introduces controlling method of flow - noise , analyzes sound field characteristics of flow - noise in seawater pipeline system and the merits and demerits of measuring the flow - noise methods in and out of the pipeline . in our experiment , a test measuring device of seawater muffler is used in a measuring chamberlet to verify that a method of reverberation chamberlet is difficult to exactly measure the low frequency flow - noise in pipeline . at the same time the insertion lose of water muffler in the low frequency was measured by the measuring chamberlet method
本文分析了海水管路系统内流噪声的产生机理，介绍了流噪声的控制方法；分析了海水管路系统中流噪声的声场特性以及流噪声管内、管外测量方法的优缺点；通过海水消声器试验测量台架，利用测量小室验证了混响箱法难以准确测量海水管路系统中的低频流噪声；用测量小室对水消声器在低频段的插入损失进行了测量。