Study of Wall Static Pressure Distribution on Flat Surface by Impinging Submerged Jet from Non-circular Orifice

Abstract

The distribution of wall static and stagnation (CP and CP_O) pressure coefficient on a flat rectangular element by impinging air jet from the hexagonal orifice is obtained from experimentation. The past research studies helped to identify key parameters such as orifice geometry, jet exit-to-plate-distance (Z/d_j), test section inclination (θ), jet Reynold number (Re), lateral distance-to-jet diameter (X/d_j), test surface type and geometry, for better and acceptable results. The experimental outcome helps to know the effect of identified key parameters on wall static and stagnation pressure on a rectangular test plate in a confined flow path. The independent nature of wall static pressure is observed for all jet Reynold number (10000 ≤ Re ≤ 50000). Higher pressure coefficient values were observed at lower Z/d_j = 1, X/d_j = 0 and θ = 0. A significant drop in CP values are seen with the increase in Z/d_j, X/d_j and θ. The experimental CP and CP_O contribution of confined flow are compared against the unconfined flow, around 48% to 58% enhancement is observed when confinement is used. Experimental pressure drop measurements across orifice were made and pressure loss coefficient (P_C) for hexagonal orifice of confined and unconfined condition are reported.