Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266100, China.
College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
Ultrason Sonochem. 2022 May;86:106018. doi: 10.1016/j.ultsonch.2022.106018. Epub 2022 Apr 29.
Hydrodynamic cavitation has been widely employed in modern chemical technology. A high-speed camera experiment is conducted to reveal the characteristics of hydrodynamic cavitation generated in one self-excited fluidic oscillator. The images obtained from the high-speed camera system are employed to describe several development stages of the hydrodynamic cavitation. The gray intensity of the images which is the volume of bubbles formed is extracted to distinguish the cavitation bubbles from the water. It is found that three regions in the fluidic oscillator could be divided according to the distance from the entrance. The inception of cavitation occurs in the region nearest the entrance. For a relatively low inlet flow rate, the whole process of cavitation could complete within the region that is the second nearest the entrance as a low pressure area appears periodically in this region. For a high inlet flow rate, the vortexes in the region farthest from the entrance are able to generate sufficient low pressures to induce the generation of cavitation. In addition, the intensity of cavitation could be reflected by the cavitation number in a self-excited fluidic oscillator.
空化水力学在现代化学技术中得到了广泛应用。通过高速摄像实验揭示了自激射流振荡器中产生的空化水力学特性。高速摄像系统获得的图像用于描述空化水力学的几个发展阶段。通过提取图像的灰度强度（即形成气泡的体积）来区分空化气泡和水。结果表明，可以根据距入口的距离将射流振荡器中的三个区域进行划分。空化的起始发生在最靠近入口的区域。对于相对较低的入口流速，由于在该区域内周期性地出现低压区，因此空化的整个过程可以在最靠近入口的区域内完成。对于较高的入口流速，远离入口的区域中的涡流能够产生足够的低压，从而导致空化的产生。此外，自激射流振荡器中的空化数可以反映空化的强度。
