Servant G, Caltagirone J P, Gérard A, Laborde J L, Hita A
Laboratoire de Modélisation Avancée des Systèmes Thermiques et Ecoulements Réels (ENSCPB), Talence, France.
Ultrason Sonochem. 2000 Oct;7(4):217-27. doi: 10.1016/s1350-4177(00)00059-6.
The use of high frequency ultrasound in chemical systems is of major interest to optimize chemical procedures. Characterization of an open air 477 kHz ultrasound reactor shows that, because of the collapse of transient cavitation bubbles and pulsation of stable cavitation bubbles, chemical reactions are enhanced. Numerical modelling is undertaken to determine the spatio-temporal evolution of cavitation bubbles. The calculus of the emergence of cavitation bubbles due to the acoustic driving (by taking into account interactions between the sound field and bubbles' distribution) gives a cartography of bubbles' emergence within the reactor. Computation of their motion induced by the pressure gradients occurring in the reactor show that they migrate to the pressure nodes. Computed bubbles levitation sites gives a cartography of the chemical activity of ultrasound. Modelling of stable cavitation bubbles' motion induced by the motion of the liquid gives some insight on degassing phenomena.
高频超声在化学体系中的应用对于优化化学过程具有重大意义。对一个露天477 kHz超声反应器的表征表明，由于瞬态空化泡的崩溃和稳定空化泡的脉动，化学反应得以增强。进行了数值模拟以确定空化泡的时空演化。通过考虑声场与气泡分布之间的相互作用，计算由于声驱动而产生空化泡的情况，得到了反应器内气泡产生的分布图。计算反应器中由压力梯度引起的气泡运动表明，它们会迁移到压力节点处。计算得到的气泡悬浮位置给出了超声化学活性的分布图。对由液体运动引起的稳定空化泡运动进行建模，为脱气现象提供了一些见解。
