Effects of sediment diameter and concentration on cavitation characteristics and mechanism

Abstract

The synergistic erosion caused by cavitation and abrasion is a common and severe problem for hydraulic machinery. In order to explore the mechanism of particles size and concentration effect on cavitation, taking the rotating disk as the research object. The solid-liquid-gas three-phase flow was calculated based on the non-homogeneous multiphase flow model, modified RNG k−εturbulence model, and ZGB model. The increase of particles size firstly inhibited the bubbles (0.02 mm ≤ d ≤ 0.1 mm) and then promoted the bubbles (0.1 mm <d ≤ 0.4 mm); When 0.27 mm < d ≤ 0.4 mm, both cavitation area and cavitation damage intensity are more significant than those of cavitation alone. When d = 0.1 mm, 1% ≤ Cv ≤ 10%, the increase of particles concentration promotes bubbles. However, that only enhances the cavitation area, but has little effect on the cavitation damage intensity. When particles severely inhibit the bubbles, the vortex rotation effect is the strongest, and the mainstream promotion and re-entrant jet inhibition effect are the strongest. The purpose of this paper is to provide some theoretical basis for exploring the mechanism of synergistic erosion.