CFD Prediction of Loss Coefficient in Straight Pipes

Abstract

Loss of head in pipes is an important factor to be considered in design of engineering systems to reduce energy costs. This loss is either due to viscous effect called friction loss or due to change in geometry like bends, elbows, expansion and contraction. The pressure loss is a function of the type of flow of the fluid, i.e., laminar, turbulent; material of the pipe; and the fluid flowing through the pipe. In present study, straight pipes of various materials, namely PVC, steel and cast iron, are analyzed using ANSYS. Equations of mass, momentum and k-e turbulence model are solved using the finite volume method. To validate the numerical tool friction, loss coefficient is determined and compared with existing experimental results. Furthermore, the effect of variation of Reynolds number on the friction loss coefficient is studied. The contours of turbulence eddy dissipation at various Reynolds number are also presented to investigate the effect of Reynolds number on turbulent kinetic energy.