Numerical investigations in the behaviour of one-dimensional bubbly flow in hydrodynamic cavitation

Abstract

Hydrodynamic cavitation has been attempted as an alternative to acoustic cavitation over past few years and this form of cavitation has been proved to hold higher potential for industrial scale processes. In this work, we have tried to investigate the dynamics of the bubbly flow in hydrodynamic cavitation with the help of numerical simulations. A continuum bubbly mixture model is used to study the one-dimensional cavitating flow through a venturi. The nonlinear dynamics of the bubbles has been modeled by Rayleigh-Plesset equation. The results of the simulations show that the bubble/bubble and bubble/flow interaction through the hydrodynamics of the flow has important effect on the behavior of the bubbly flow. Effect of parameters such as downstream recovery pressure, venturi to pipe area ratio, initial bubble void fraction in liquid and initial bubble size in the flow on the dynamics of the flow has been studied. Based on the results of the simulations, recommendations have been made for an effective design and scale-up of a hydrodynamic cavitation reactor.