Experimental and simulation study of the effect of gravity on the solid-liquid two-phase flow and erosion of ball valve

• The effect of gravity which will hugely affect the erosion characteristics is considered. • DEM takes into account collisions between particles, making the result more accurate. • The erosion rate of the surface of the erosion plate behind the valve increases first and then decreases along the center line. • The surface of the erosion plate will have ripple erosion texture after the particles impact at a small angle. The ball valve is an important control component in the pipeline hydraulic transmission system. Its internal solid-liquid two-phase flow and erosion characteristics have an important effect on the safety and stability of the entire pipeline system. Therefore, the erosion characteristics and positions of the ball valve body, the spool flow channel, and the pipeline surface behind the valve should be accurately predicted to ensure the safety of the pipeline. In this study, the experimental setup of the ball valve was designed. The experimental study on the erosion caused by the solid-liquid two-phase flow on the inner surface of the ball valve was conducted. And the numerical calculation research based on the CFD-DEM simulation method was performed. Results show that the placement of the ball valve has a great effect on the two-phase flow and erosion distribution inside the valve; the surface of the erosion plate will form a corrugated texture under the impact of particles at small openings; the placement method changes from vertical to horizontal due to the change in the direction of gravity. As a result, the particle distribution easily gathers near some wall surfaces to form a protective layer, which reduces the erosion rate.