超声空化场中的球旋转

根据P.Langevin对声辐射力的推算和C.Eckart的声流理论,实现了超声喷泉中一个球体的旋转和两个球体按相反方向的旋转,同时观察到这些球体的旋转随超声功率的增大而加速。这种由频率1.7MHz和电功率45W的超声所产生的超声喷泉,可以看作是一种向上喷射的超声空化场,它拥有一种单方向的辐射力和对称的回旋声流,正是这种空化场所具有的这类典型的声学非线性特性才为球体的旋转提供了稳定的旋转力矩。

The sphere gyration in an ultrasonic cavitation field

Based on radiating force prediction by P.Langevin and sound streaming theory by C.Eckart stable gyration of one ball and two balls rotating in opposite directions was realized in an ultrasonic fountain.It is found that the gyration of the balls accelerates as the ultrasonic power increases.The ultrasonic fountain generated using ultrasound with a frequency of 1.7 MHz and an electric power of 45W can be considered as a jetting-up ultrasonic cavitation field.It has a single-direction radiating force and the symmetrical-loop stream which are the typical acoustic non-linear features possessed by this kind of field and which provides the steady torque to make the balls rotate.