Abstract:
To investigate the influence of mass and heat transfer properties of bubbles on the acoustic cavitation effect of double bubbles near a rigid wall, a novel model combining the modified Keller-Miksis equation with the Noble-Abel-Stiffened-Gas state equation is used to study the cavitation effect of double bubbles with mass and heat transfer properties near a rigid wall under ultrasonic. The results are compared with the caviation effect of double bubbles without mass and heat trasfer propeties. The results indicate that, regardless of the coupling effect between the double bubbles, the maximum expansion radii of both large and small bubbles with mass and heat transfer increase, their collapse times prolong, and the compression ratios of both large and small bubbles decrease as wall distance varies. By inspecting the variation of the collapse velocity of the double bubbles with wall distance, it is found that regardless of the coupling effect between the double bubbles, the collapse velocity of the small bubble with mass and heat transfer is greater than that of the small bubble without mass and heat transfer, while the collapse velocity of the large bubble with mass and heat transfer is smaller than that of the large bubble without mass and heat transfer. By examining the variation of the jet velocity of the double bubbles with normalized distance, it is revealed that the disparity in the jet velocities of the two types of bubbles (with and without mass and heat transfer) is minor, suggesting that the mass and heat transfer properties of the bubbles have a negligible influence on the jet velocity. By observing the variation of the internal temperature of the double bubbles with wall distance, it is discovered that, regardless of the coupling effect between the double bubbles, the internal temperatures of both large and small bubbles with mass and heat transfer are lower than those of the large and small bubbles without mass and heat transfer.