Moholkar V S, Kumar P S, Pandit A B
University Department of Chemical Technology, University of Bombay, Matunga, India.
Ultrason Sonochem. 1999 Mar;6(1-2):53-65. doi: 10.1016/s1350-4177(98)00030-3.
A comparative study of hydrodynamic and acoustic cavitation has been made on the basis of numerical solutions of the Rayleigh-Plesset equation. The bubble/cavity behaviour has been studied under both acoustic and hydrodynamic cavitation conditions. The effect of varying pressure fields on the collapse of the cavity (sinusoidal for acoustic and linear for hydrodynamic) and also on the latter's dynamic behaviour has been studied. The variations of parameters such as initial cavity size, intensity of the acoustic field and irradiation frequency in the case of acoustic cavitation, and initial cavity size, final recovery pressure and time for pressure recovery in the case of hydrodynamic cavitation, have been found to have significant effects on cavity/bubble dynamics. The simulations reveal that the bubble/cavity collapsing behaviour in the case of hydrodynamic cavitation is accompanied by a large number of pressure pulses of relatively smaller magnitude, compared with just one or two pulses under acoustic cavitation. It has been shown that hydrodynamic cavitation offers greater control over operating parameters and the resultant cavitation intensity. Finally, a brief summary of the experimental results on the oxidation of aqueous KI solution with a hydrodynamic cavitation set-up is given which supports the conclusion of this numerical study. The methodology presented allows one to manipulate and optimise of specific process, either physical or chemical.
基于瑞利 - 普列赛特方程的数值解，对水力空化和声学空化进行了对比研究。在声学空化和水力空化条件下，均对气泡/空穴行为进行了研究。研究了变化的压力场对空穴坍塌（声学空化为正弦波形式，水力空化为线性形式）以及对后者动态行为的影响。已发现，诸如声学空化情况下的初始空穴尺寸、声场强度和辐照频率，以及水力空化情况下的初始空穴尺寸、最终恢复压力和压力恢复时间等参数的变化，对空穴/气泡动力学有显著影响。模拟结果表明，与声学空化下仅出现一两个脉冲相比，水力空化情况下气泡/空穴的坍塌行为伴随着大量幅度相对较小的压力脉冲。结果表明，水力空化对操作参数和由此产生的空化强度具有更强的控制能力。最后，给出了用水力空化装置氧化碘化钾水溶液的实验结果简要总结，该结果支持了本数值研究的结论。所提出的方法使人们能够对特定的物理或化学过程进行操控和优化。
