Mechanisms of Pressure Loss in Chamfered Orifice Plates: Coupled Effects of Plate Thickness and Reynolds Number

Abstract To study the effect of chamfered structure on the flow characteristics of a throttled orifice plate, orifice plates with different thicknesses and chamfered structures were analyzed using the computational fluid dynamics (CFD) method. The results show that the thickness of the orifice plate significantly affects the flow characteristics, and the influence of the Reynolds number ( Re ) on the pressure loss coefficient shows an opposite trend on thin and thick orifice plates (the loss of the thin plate increases with the increase of Re , while that of the thick plate decreases). The chamfered structure effectively improves the flow pattern in the orifice plate and reduces the pressure loss. Lower pressure-loss coefficients are usually obtained with a chamfer angle of 30°–45°. In addition, the thickness of the openings affects the optimal chamfer angle: as thickness increases from 0 to 2.5 mm, the optimal angle shifts from 15° to 45°.