功率超声珩磨磨削区单空化泡动力学及其辐射声场

Dynamics and Radiated Acoustic Field of Single Cavitation Bubbles in the Grinding Area of Power Ultrasonic Honing

功率超声珩磨加工过程中会在磨削区产生大量的空化泡,空化泡在磨削区的振动以及空化泡溃灭时释放出的冲击压力是诱发功率超声珩磨切削颤振的重要因素之一.以磨削区单个空化泡为研究对象,运用Rayleigh方程的推导方法,结合空化泡动力学及超声珩磨的基本理论,建立了磨削区单个空化泡的动力学模型和辐射声压模型,并对其进行了数值模拟.结果表明:磨削区空化泡在极短的时间内历经了生长、溃灭的过程;对于磨削区较小的空化泡,其初始半径越大,距离空化泡的距离越近,单个空化泡辐射的声压值就越大.

Power ultrasonic honing in the machining process particularly generated abundant cavitation bubbles. The shock pressure released by the collapsing cavitation bubbles and cavitation bubble vibration in the grinding area was very important factor for inducing the cutting chatter generated by power ultrasonic honing. Taking a eavitaion bubble in the grinding area into account, the method of Rayleigh equation and the grinding mechanism of power ultrasonic honing were combined. The dynamic model of a single cavitation bubble and radiation acoustic model in the grinding zone were established and numerically simulated. The results show that a cavitation bubble in the grinding zone constantly grows and collapses within a very short time, and that for a smaller cavitation bubble, the bigger the initial radius of cavitation bubble is and the closer the distance to cavitation bubble is, the greater radiation pressure of a cavitation bubble has.