Numerical analysis of flow characteristics of a fluid flowing through an orifice in a marine piping system

Abstract

Over the last few decades expensive research work has been performed by many researchers on the monitoring of rate of fluid flow through various pipes. Moreover, in the marine industry, it's important to conduct a detailed analysis of the uncertainties associated with flow measurement. It has been also seen that the coefficients, which are used for orifices are based on empirical data. Therefore, accurately predicting the impact of complex geometry and flow separation from the orifice in the flow have become crucial challenges for many researchers. From the review of the literature, it has been noted that a systematic detailed investigation of the flow through the orifice has not been done so far. Thus, in the present study a systematic details numerical investigation has been conducted for incompressible turbulent flow of water through a square edge orifice plate with considering various Reynolds numbers ranging from 153 to 273 and Bita ratios from 0.3432 to 0.6289. The standard design of ISO 5167-2 has been used in the present investigation. In this work, the simulations have been performed by using the ANSYS Fluent. The standard k-ε model has been selected for the turbulence flow analysis. The streamline contour, velocity contour, pressure contour, centreline axial velocity, wall pressure, radial profile of turbulent kinetic energy, and turbulent dissipation rate are presented in the results and discussion section in a systematic manner. From the analysis, it has been noted that the pressure drops from the orifice plate up to the vena contracta increase with increasing the Reynolds numbers and the beta ratio. It has also been observed that the pressure affects the jet-like flow in the core region, the recirculation zone, the reattachment, and the shear regions on the downstream side of the orifice. The location of vena contracta is also be estimated from present CFD simulations. Thus, this analysis improves the accuracy of coefficients. Consequently, error may be minimized in view of monitoring the rate of fluid flow in marine systems.