气核密度分布的声学测量技术研究

Investigation of the nuclei population distribution measurement using acoustic inverse method

文章从气泡流中的气泡密度分布与复声速之间的关系式出发,推导得到气泡的密度分布与声速系数以及声衰减系数的方程组。文中建立的声学测核技术采用带约束条件的最小化方法求解该方程组,得到气泡的密度分布。此外,设计和建立了一套完整的设备用于气核的声学测量,并基于LabVIEW图形化开发平台开发了一套气核声学测量软件。最后,应用图象显微方法测量了气核密度分布并与声学测核方法得到的结果进行比较,表明两种方法得到的气泡分布曲线吻合较好。

The nuclei population distribution has remarkable influence on the cavitation.Therefore the nu-clei population density measurement is fundamental for the nuclei investigation.Applying the minimizing algorithm with some constraints,the equations of sound propagation through a bubbly liquid were solved and the nuclei population density was obtained in this paper.Furthermore,an acoustic test system for mea-suring nuclei population density was established.And the acquisition and analysis software was developed using graphic language LabVIEW.Also,many tests were implemented in the laboratory to measure the nu-clei population density and the satisfied results were obtained.In addition,the microphotography method was tested to measure the nuclei population distribution.The comparison between the results obtained by acoustic method and by microphotography method was made and showed the good agreement.