Study on the Collapse Process of Cavitation Bubbles Near the Concave Wall by Lattice Boltzmann Method Pseudo-Potential Model

In this paper, the lattice Boltzmann pseudo-potential model coupled the Carnahan–Starling (C-S) equation of state and Li’s force scheme are used to study the collapse process of cavitation bubbles near the concave wall. It mainly includes the collapse process of the single and double cavitation bubbles in the near-wall region. Studies have shown that the collapse velocity of a single cavitation bubble becomes slower as the additional pressure reduces, and the velocity of the micro-jet also decreases accordingly. Moreover, the second collapse of the cavitation bubble cannot be found if the additional pressure reduces further. When the cavitation bubble is located in different angles with vertical direction, its collapse direction is always perpendicular to the wall. If the double cavitation bubbles are arranged vertically, the collapse process of the upper bubble will be quicker, as the relative distance increases. When the relative distance between the bubbles is large enough, no second collapse can be found for the upper bubble. On the other hand, when two cavitation bubbles are in the horizontal arrangement, the suppression effect between cavitation bubbles decreases as the relative distance between the bubbles increases and the collapse position of cavitation bubbles moves from the lower part to the upper part.