Erosion Wear and Flow Characteristics of Tri-eccentric Butterfly Valves under Liquid‒solid Two-phase Flow

Abstract

Excellent sealing performance drives the tri-eccentric butterfly valve’s extensive adoption across wastewater treatment sector. Erosion wear is an important cause of leakage and damage in tri-eccentric butterfly valves. Valve surface erosion is affected by the vorticity, particle shape, velocity, and other factors. This paper uses the Computational Fluid Dynamics–Discrete Element Method (CFD-DPM) to build an erosion model based on the Erosion-Corrosion Research Center (E/CRC) methodology, investigating the valve opening’s influence on erosion rates under sand particle flow conditions. The two-way coupling phase interaction, wall roughness, particle diameter distribution, and particle geometry are considered in the proposed erosion model. The numerical model is validated through wear and flow experiments. Moreover, the vorticity and velocity correlation coefficients are investigated, with those in the valve stem region exceeding 0.9. The influence of vortex core regions on particle trajectories is investigated, revealing that the velocity angle approaches ±90° in vortex core regions. The numerical results indicate that the sealing surface is particularly vulnerable to wear from particle erosion, exhibiting a peak value of 8.53×10-7 kg·m-2·s-1. Additionally, wall erosion rate is influenced by vorticity, which alters the angular velocity of solid particles and affects vortex formation.

Keywords

• tri-eccentric butterfly valve
• erosion wear
• computational fluid dynamics–discrete element method vorticity
• sealing surface