Correlation analysis between underwater noise and Liutex for DTMB4119 propeller

Propeller is an important equipment of ocean structures.It has characteristics of complex geometry and periodic vortex shed,which means high research value.This paper takes DTMB419 propeller as the research object.A detailed study is conducted on the wake vortices in non-cavitation state and cavitation state.Three vortex identification methods are used to compare the vortices capture effects from downstream sections and three-dimensional perspectives.The results show that,the third-generation vortex identification technologyΩ_(R)shows obvious advantages.At the same time,FW-H equation is used to predict propeller noise,and the relationship between nonlinear sound source distribution and vortices distribution is analyzed.It is found that the distribution of Lighthill tensor is consistent withΩ_(R),which proves the advantages and potential of third-generation vortex identification technology from acoustic perspective.