Turbulent Flow over a Flat Plate Using a Three-equation Model

Khalid Alammar

doi:10.19026/rjaset.7.417

Abstract

Aim of this study is to evaluate a three-equation turbulence model based on the Reynolds averaged Navier-Stokes equations. Boussinesq hypothesis is invoked for determining the Reynolds stresses. An average turbulent flat plate flow was simulated. Uncertainty was approximated through validation. Results for the mean axial velocity and friction coefficient were within experimental error.

Highlights

The problem of turbulence dates back to the days of Claude-Louis Navier and George Gabriel Stokes, as well as others in the early nineteenth century
Large Eddy Simulation (LES) is another tool that somewhat bridges between Direct Numerical Simulation (DNS) and Reynolds-Averaged Navier-Stokes (RANS) methods
While DNS and LES are fairly accurate for modeling turbulent flows, they remain limited to relatively low-range Reynolds numbers

Summary

INTRODUCTION

The problem of turbulence dates back to the days of Claude-Louis Navier and George Gabriel Stokes, as well as others in the early nineteenth century. Reynolds stresses and turbulent intensities were presented and discussed, along with visualization of flow structure. Large Eddy Simulation (LES) is another tool that somewhat bridges between DNS and Reynolds-Averaged Navier-Stokes (RANS) methods. While DNS and LES are fairly accurate for modeling turbulent flows, they remain limited to relatively low-range Reynolds numbers. Turbulence modeling includes eddy viscosity models which utilize the Boussinesq hypothesis for relating the Reynolds stresses to the average flow field, Hinze (1975). While such models vary in complexity, they share several shortcomings, including isotropy of the eddy viscosity and the lack of generality in wall treatment Such shortcomings lead to poor results in separated flows and other non-equilibrium turbulent boundary layers, Yamamoto et al (2008). C2 is another constant length parameter attributed to wall roughness

NUMERICAL PROCEDURE

RESULTS AND DISCUSSION

CONCLUSION