Simulation of turbulence flow in OpenFOAM using the large eddy simulation model

Abstract

Turbulent flow in fluid dynamics is used to describe fluid motion characterized by unpredictable fluctuations in pressure and flow velocity. Turbulence is generated when an area of fluid flow has an excessive amount of kinetic energy, which exceeds the damping impact of the viscosity of a fluid. The primary goal of turbulence modeling is to establish a mathematical model to predict time-averaged velocity, turbulence kinetic energy, and pressure rather than compute the fully turbulent flow pattern as a function of time, as is done in large eddy simulation (LES) and Reynolds-averaged Navier–Stokes simulations. Computationally solving the Navier–Stokes equation of motion to simulate turbulent flows necessitates resolving a wide range of length scales and times, all of which impact the flow field. The current study is concerned with the investigation of turbulence kinetic energy through the use of an LES model. The kinetic energy caused by turbulence is analyzed at the outlet and inlet. Along with the pressure, the fluctuations, as well as the mean velocity at the outlet and inlet, are examined. The C++-based programming is done to compute the turbulent flow in OpenFOAM. The computations made in OpenFOAM and Python show great agreement. For a better understanding of readers, graphs and animation are given.

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“…In contrast, the laminar regime describes the situation where fluid flows in perfectly parallel layers with no separation between them. Muhmmad et al [ 49 ] computed the turbulence flow in FOAM.…”