Experimental study on effects of geometric and hydrodynamic parameters on performance of multi-holed orifice flowmeters

Abstract Multi-holed Orifices (MOs) are widely used in swirling, cavitating and developing flows to reduce pressure losses. This study focuses on analysis of MOs for developing turbulent flows. A large number of experiments were performed, exploring the number of holes (n), Equivalent Diameter Ratio (EDR), compactness ratio (C), plate thickness ratio (s/d) and upstream developing length (L/D) in the Reynolds number (ReD) range of 24,500–55,500. An empirical correlation of pressure loss coefficient and flow rate is formulated. It is observed that pressure loss coefficient decays with the fourth power of EDR. A comparative study of the experimental data with the literature is presented to ensure consistency and reliability.