【摘要】 为探究超声空化作用对颗粒破碎的影响效果,基于空化泡的动力学基本方程,利用空化过程Matlab数值方法分析了超声频率和液相黏度两个关键因素对超声空化作用强度的影响。在数值分析的基础上,通过超声空化破碎试验探究了超声频率和浆液浓度的影响效果。试验结果表明:经过一定时间的超声作用,颗粒群中位粒径D₅₀及10%体积累计粒径D₁₀大幅减小,超声空化颗粒破碎作用明显。超声频率和物料浆液浓度越低,空化作用越强,颗粒破碎效果越好;同时,介质的存在可以有效增强超声作用下空化微射流的壁面效应,增强颗粒的破碎效果,但过多的介质会影响超声波的传导,减弱空化作用。更多还原

【Abstract】 In order to investigate the effect of ultrasonic cavitation on particle breakage, a numerical analysis method was used to analyze the effect of ultrasonic frequency and liquid viscosity on ultrasonic cavitation intensity based on the kinetic basic equation of cavitation bubble. Based on the numerical analysis, the effect of ultrasonic frequency and liquid viscosity on cavitation was studied by ultrasonic cavitation crushing test. The experimental results show that D₅₀ and D₁₀ of the crushed particles are decreased significantly after a certain period of ultrasound cavitation. The lower the ultrasonic frequency and the slurry concentration are, the stronger the cavitation effect is, and the better the effect of the particle crushing is. Meanwhile, the existence of media can effectively enhance the wall effect of the cavitation micro-jet under the ultrasound, which improves the particle crushing efficiency. However, too many media will affect the conduction of ultrasound, reduce the role of cavitation.更多还原