Research on the collapse characteristics of single cavitation bubble near solid particle by the VOF method

In this paper, the collapse behavior of a single cavitation bubble at different distances near a solid particle of typical scales is numerically simulated and researched with the volume of fluid (VOF) method. Based on the key parameters analysis of the pressure field, velocity vector, collapse time the tendency of cavitation bubble collapse characteristics at different distances during the change of particle size is studied with the variable of the distance and relative size between the particle and the cavitation bubble. The dimensionless distance parameter 'γ' is specifically presented in the simulation process, the cavitation bubble collapse impact is largely directed to the particle when 3>γ > 2, while the wall hardly affects the interaction between the cavitation bubble and the solid particle as γ > 3. The results illustrate that as the solid particle and wall exist, the distance and particle size affect both the peak collapse pressure and the collapse jet velocity of the cavitation bubble, and the influence of solid wall on the cavitation bubble at the same distance is much greater than that of solid particles. When the particle size increases, the particle gradually affects the cavitation bubble in a way similar to the wall. While as the distance decreases or the particle size increases, the influence of particle and wall on the evolution process of the cavitation bubble expands, meanwhile, the collapse pressure and collapse jet velocity of the cavitation bubble are promoted with the optimized distance and particle size, which brings marvelous cavitation effect. The numerical methods and conclusions of this paper provide a valuable reference for cavitation applications of sand-containing fluids.