摘要
为了探索超声强化超临界CO2流体中空化泡的共振频率特性,根据Rayleigh-Plesset方程推导出了空化泡共振频率随空化泡初始半径、流体压力和温度的变化规律.结果表明:超临界CO2流体中空化泡的共振频率随空化泡的初始半径增大而减小;随流体压力的增大先减小后增大,在流体压力约为18MPa时达到最低值;并随流体温度的升高而增大.在相同的初始半径下,超临界CO2流体中空化泡的自然共振频率高于其在水中的自然共振频率.超声波频率与空化泡的自然共振频率相近时,空化泡在一个声周期内崩溃所需的声压最低.
In order to reveal the characteristics of resonant frequency of the cavitation bubbles in supercritical fluid CO2 radiated with ultrasonic, the laws of the resonant frequency varying with the original radius of the bubbles, the fluid pressure and the fluid temperature were investigated based on the Rayleigh-Plesset equation. The results indicate that the resonant frequency of cavitation bubbles in supercritical fluid CO2 decreases with the increase in the original radius, increases with the fluid temperature, and decreases with the increase in fluid pressure till to a minimum value at 18 MPa. It is also found that, at the same initial bubble radius, the cavitation bubbles in supercritical fluid CO2 is of higher resonant frequency than that in water, and that the acoustic pressure for the cavitation bubble collapse in a ultrasonic period reaches the lowest value when the ultrasonic frequency is close to the natural resonant frequency of cavitation bubbles.
出处
《华南理工大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2008年第7期32-35,41,共5页
Journal of South China University of Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(10674048)
广东省自然科学基金资助项目(06025714)
广东省科技计划项目(2007B031402003)
关键词
超临界CO2流体
超声
空化
共振频率
压力
温度
supercritical fluid CO2
ultrasonic
cavitation
resonant frequency
pressure
temperature