The role of the surface bubble on the cavitation bubble collapse

Abstract: In this work, wall pressure fluctuations and shear stresses of a rigid wall induced by the collapse of a cavitation bubble with and without a surface bubble are investigated numerically by a Volume of Fluid solver. Three different initial stand-off distances, h is the distance between the bubble centre and the wall, and Ro is the initial bubble radius) are examined for the cavitation bubble. The shear stresses are merely altered by the surface bubble while the amplification for wall pressure fluctuations caused by the collapse of the surface bubble is identified. Keywords: Bubble dynamics, Waterhammer, Shock wave, Re-entrant jet