Fu Guihua, Luo Jing, Xu Weilin, Tang Jiguo, Wang Hang
State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China.
State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China.
Ultrason Sonochem. 2025 Sep;120:107495. doi: 10.1016/j.ultsonch.2025.107495. Epub 2025 Aug 5.
How to efficiently utilize cavitation to promote chemical reactions or degrade microorganisms is a concern in the fields of biological and chemical engineering. Changes in liquid temperature can affect bubble dynamics, thereby influencing chemical reaction rates or microbial degradation efficiency. This study used the method of corona discharge induced bubbles, combined with high-speed camera system and temperature control system, to investigate the effect of salted water temperature on the bubble collapse behavior in the free field and below the liquid surface. In the free field, it was found that salted water temperature affected the maximum radius, minimum first contraction radius, expansion time and collapse time of bubble. And the above parameters showed an increasing trend with the increase of salted water temperature. Further measurements using high-frequency pressure testing system revealed that as salted water temperature increased, the pressure peak of shock wave and relative energy gradually decreased. The above experimental results were mainly due to the effect of salted water temperature on evaporation and condensation rate, which led to different microjet and shock wave behaviors under varying boundary conditions. The study found that as salted water temperature increased (10 ℃ - 40 ℃), the microjet velocity and the maximum pressure peak of the shock wave below the free liquid surface gradually decreased. A novel phenomenon was observed where bubble expansion in high-temperature salted water induced secondary cavitation, forming a "satellite bubble" pattern. These findings provided a new idea to controlling cavitation intensity through temperature in the actual cavitation scene.
如何有效利用空化作用来促进化学反应或降解微生物是生物和化学工程领域关注的问题。液体温度的变化会影响气泡动力学，从而影响化学反应速率或微生物降解效率。本研究采用电晕放电诱导气泡的方法，结合高速摄像系统和温度控制系统，研究盐水温度对自由场和液面以下气泡坍塌行为的影响。在自由场中，发现盐水温度影响气泡的最大半径、首次收缩最小半径、膨胀时间和坍塌时间。上述参数随盐水温度的升高呈上升趋势。使用高频压力测试系统进一步测量发现，随着盐水温度升高，冲击波压力峰值和相对能量逐渐降低。上述实验结果主要是由于盐水温度对蒸发和冷凝速率的影响，导致在不同边界条件下产生不同的微射流和冲击波行为。研究发现，随着盐水温度升高（10℃-40℃），自由液面以下微射流速度和冲击波最大压力峰值逐渐降低。观察到一种新现象，即高温盐水中气泡膨胀会诱导二次空化，形成“卫星气泡”模式。这些发现为在实际空化场景中通过温度控制空化强度提供了新思路。
