FLOW CHARACTERSTIC OF SEGMENTAL OROFICE PLATES

Abstract

This thesis presents the results of the experimental investigation concerning the flow through segmental orifice plates in pipe. The experiments were conducted in a 105 nun diameter pipe, in a recirculatory flow system using segmental orifice plates of orifice area to pipe area a/A, 01 0.20, 0.32, 0.49, 0.66 and 0.84. The data collected in the present investigation alongwith the data collected from literature have been analysed to study the variation of discharge coefficient Cd of segmental orifice plates with relevant flow and geometric parameters. It has been found that Cd depends on Reynolds number Re and a/A. For higher Re values Cd depends only on a/A and is given•by Cd = 0.63 + 0 55(a/A)3'4°. The effect of sediment concentration on Cd was also studied. For this, coal (sp. gr. 2.046) with median size 0.355 mm and geometric standard deviation 1.052 was used with volumetric concentrations varying from 0.5 to 5.5 percent. ifowever, due to limited runs with sediment laden flows no conclusive results could be drawn.