湍流对流动管道中声强测量的影响

实际声强测量大多是在流动环境条件下进行,因此湍流对声强测量的影响是人们十分关心的工程实用问题.文章结合声强和湍流边界层等相关领域的技术,对流动条件下的声强技术进行了研究分析,导出了由湍流边界层引起的声强的具体表达式.应用Corcos建立的湍流边界层脉动压力模型,对湍流边界层脉动压力诱导的声强进行了数值计算分析,分析了测量传感器间距、马赫数等对声强测量的影响.

Influence of Turbulent Flow on Sound Intensity Measurement in a Duct with Mean Flow

A large number of sound intensity measurements are carried out in the case of flow which exists in situ, and therefore the effect of turbulent flow on sound intensity measurement is of practical concern.In this paper, the techniques in the areas of sound intensity and turbulent boundary layer (TBL) are combined. And the sound intensity caused by the pressure fluctuation beneath a turbulent boundary layer in a duct with mean flow is analyzed and an expression for such sound intensity is derived.Based upon the Corcos model of the pressure fluctuation beneath a turbulent boundary, the sound intensity caused by the TBL pressure fluctuation in a duct with mean flow is examined numerically. Some effects of the distance between microphones, and Mach number or flow velocity, etc. on the sound intensity measurement in a duct with mean flow are investigated also.