Numerical analysis of fluid dynamics in a novel 30 MPa back pressure valve with dual throttling channels and a spherical valve core

Abstract

The rapid development of carbon neutrality and renewable energy technologies has imposed higher demands on high-pressure fluid control systems, while simultaneously creating diversified application scenarios for high-performance back pressure valves. Typical applications include pressure-resistant pipeline systems for green hydrogen storage and transportation, as well as for handling supercritical carbon dioxide under extreme pressures. This study proposes a novel back pressure valve featuring a ruby-made spherical core with dual-throttle channels, which addresses the limitations of conventional back pressure valves employing conical, cylindrical, or spring-diaphragm valve cores/pressure-regulating mechanisms. The innovative design effectively addresses the incompatibility, long-term leakage risks, and mechanical interference often encountered by traditional backpressure valves in high-pressure environments. The relationship between inlet pressure, maximum flow velocity, and maximum turbulent kinetic energy with valve opening were revealed based on experimentally validated numerical model. The results indicate that with a valve opening of 0.39 mm, the back pressure can reach up to 30 MPa, demonstrating excellent applicability across an inlet pressure range of 2–30 MPa. Additionally, when the valve opening is less than 6 mm, pressure suppression occurs within the valve chamber. Fluid-structure interaction analysis reveals that the maximum stress, the valve seat edge under peak pressure concentrated, reaches 192.54 MPa, leading to a deformation of 4.85 $\times {10}^{-3}$ mm. Finally, a comparison of valve cores made from ruby, 316-grade stainless steel, zirconium oxide, and silicon nitride ceramics shows that all materials meet the back pressure regulation requirements, with ruby offering the best economic efficiency.