Sound speed in bubble film of ship wakes  

作　　者：ZHANG JianSheng LIN ShuYu LIU Peng MIAO RunCai YANG WanMin 

机构地区：[1]Physics Department,Shaanxi Normal University,Xi’an 710062,China [2]Math-physical Department,Xi’an Technological University,Xi’an 710032,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2008年第1期64-71,共8页中国科学：物理学、力学、天文学（英文版）

基　　金：Supported by the National Natural Science Foundation of China(Grant No.10274046);Pre-study Fund of Military Equipment(Grant No.51448030101ZK1801)

摘　　要：As is distinct from general gas-liquid two-phase flow,a large number of bubbles with different diameters belong to ship wakes.Feasibility of Laplace equation,used to calculate wake sound speed(WSS),is confirmed based on differential postula- tion.Defect for calculating the adiabatic sound speed of gases in references is showed,and a concept of WSS is proposed clearly.A minimum WSS of 24.5 m/s is got when bubble ratio reads 0.5 according to the calculation when bubble dimen- sion is less than that of resonance.Also a weak dependence of WSS on pressures is predicted.WSS from calculation corresponds with the experimental data of ref- erences well in high frequency domain,when the actual scale of bubbles is greater than the resonant scale.As is distinct from general gas-liquid two-phase flow, a large number of bubbles with different diameters belong to ship wakes. Feasibility of Laplace equation, used to calculate wake sound speed (WSS), is confirmed based on differential postulation. Defect for calculating the adiabatic sound speed of gases in references is showed, and a concept of WSS is proposed clearly. A minimum WSS of 24.5 m/s is got when bubble ratio reads 0.5 according to the calculation when bubble dimension is less than that of resonance. Also a weak dependence of WSS on pressures is predicted. WSS from calculation corresponds with the experimental data of references well in high frequency domain, when the actual scale of bubbles is greater than the resonant scale.

关 键 词：SHIP WAKE BUBBLE film LAPLACE equation RESONANT frequency SOUND speed 

分 类 号：O359[理学—流体力学]