Effects of solid particle concentration on solid particle-water cavitating jet evolution in Venturi tube

The solid particle-water cavitating jet (SPWCJ) in the Venturi tube is one kind of complex multiphase flow. In this study, the effects of different solid particle concentrations on the SPWCJ development were investigated. Solid particle diameter varied from 0.1 to 0.3 mm, and concentrations were 0.5%, 1.0%, and 1.5%. Effect laws were built via systematical discussions on the distribution of cavitation bubbles from experimental measurement, variation of dimensionless number from theoretical analysis, and variation of vapor content from numerical simulation. At the T0ms and T0+15ms moments, the length of cavitation bubbles became longer, the value of dimensionless number was greater than 1, and the vapor content increased with concentration. SPWCJ development was promoted. For the T0+55ms and T0+91ms moments, from 0.5% to 1.0%, the length of unshedding cavitation bubbles increased; the number of shedding bubbles was more, and corresponding distribution scope became larger; the value of dimensionless number was greater than 1; vapor content grew. SPWCJ development degree became more intense. From 1.0% to 1.5%, they had contrary variations. SPWCJ development degree became weaker. Mechanisms were revealed as well. Positive total slip velocity increased and negative one decreased, turbulent kinetic energy became more intense, vorticity increased, and virtual mass force increased to reduce pressure to stimulate SPWCJ development. They had contrary variations to let pressure increase to make evolution degree become weaker. Laws of pressure variation with concentration under different moments were built to accurately demonstrate reasonableness of mechanism explanations.