Effect of the valve throat on the characteristics of the sleeve regulating valve

摘要

In order to satisfy the requirements of regulating performance in pipeline systems, the effects of the cross section shape of valve throats are investigated.The Computational Fluid Dynamic (CFD) which based on the finite-volume method was employed to analyze the internal flow characteristics and relative coefficients.Three types of valve throats including the ellipse-shaped valve throats, the V-shaped valve throats and the fan-shaped ones are discussed.The results show that the flow coefficient depends much on the geometry of the flow passage.The valve with V-shaped throats has a similar equal percentage flow characteristic.The valve with fan-shaped throats has a similar linear flow characteristic.The relative characteristics change with the flow cross section shapes.The intemal flow of the valve is more complex in small opening.Due to the special internal structure of the sleeve regulating valve, the flow direction suddenly changes when fluid flows through the valve chamber.Energy loss vicinity of the spool is relative large.In the case of certain flow, the jet will be generated inside the valve throats when valves are in small opening.