Bjerknes力对微气泡运动特性的影响

摘要

Using the bubble control equation, the motive behaviors of micro-bubble in acoustic standing wave field are numerically simulated with regarding water as a working medium. The effects of Bjerknes forces on bubble trajectory are investigated. Our results show that the coefficient of Bjerknes forces varies several orders of magnitude with different acoustic pressure values or different locations. During micro-bubble moving to the acoustic pressure antinode area, primary Bjerknes force increases at first and then decreases, but secondary Bjerknes force increases continuously. The interaction of them forms a ring around acoustic axis, and the greater acoustic pressure value will induce the greater ring.%以水为工作介质,利用气泡的控制方程,模拟微气泡在驻波声场中运动特性,分析了Bjerknes力对气泡运动轨迹的影响.结果表明:不同声压下,同一位置或相同声压不同位置的气泡所受到的Bjerknes力的系数相差几个数量级,气泡在向声压波腹区域移动过程中,所受的主Bjerknes力先增大后减小,而次Bjerknes力一直增大,它们的作用使气泡在声轴周围形成一个圆环,声压越大,圆环越大.