Numerical Study of Erosion Wear Characteristics in a High-pressure Black Water Angle Valve by Using CFD-VOF-DPM Method

High-pressure black water angle valves are essential equipment of black water flash treatment systems in the coal gasification process, and they usually suffer from a high risk of erosion wear failure. In this study, computational fluid dynamics (CFD), combined with the discrete particle method (DPM) and the volume of fluid (VOF) method, was used to study the flow characteristics and erosion wear phenomenon in high-pressure black water angle valves under different valve cavity radii and opening angles. In particular, a new parameter, the drift index, was introduced to analyze the bias flow phenomenon in the throttling zone. With the increase in valve cavity radius, the drift index first decreases and then increases, and the influence of the valve cavity radius gradually weakens with the increase in the valve opening. It was found that, with the increase in valve cavity radius, the average erosion wear rate of the valve body decreases first and then increases. When the valve cavity radius was 132 mm, the average erosion wear rate of the valve body was the smallest. Therefore, the optimization of the valve cavity radius selection value can reduce the erosion wear damage of the high-pressure black water angle valve and increase its operational dependability.