Abstract

Perforated plates are widely used in order to reduce flow non-uniformities, to retard onset of turbulence and to attenuate cavitation. There are some studies carried out for investigation of effects of geometrical parameters of perforated plates and flow parameters on pressure loss coefficient. However the related studies were performed at high Reynolds numbers in the order of 10⁵. This work aims to research pressure loss through a variety of perforated plates having different geometrical aspects in a mean flow Reynolds number range of 2500≤Re_m≤9500 and a porosity range of 0.064≤β≤0.331 for different numbers of holes ranging in 5≤n_h≤26. The dependency of the pressure loss upon the Reynolds number, the porosity of the perforated plates, the number and the distribution of the holes is investigated under no cavitating conditions. An expression, Eu=0,67β^-2,24 , describing the relationship between the pressure loss coefficient and the porosity of perforated plate is proposed with a mean deviation of ±12% for easy estimation of pressure loss coefficient at moderate Reynolds numbers of turbulent flow regime as a practical solution.