Turbulence Characteristics of Classical Hydraulic Jump Using DES

Abstract

This paper performs a three-dimensional, unsteady, detached-eddy simulation (DES) of a classical hydraulic jump with an inlet Froude number of 8.5. The volume of fluid (VOF) method with a high-resolution interface capturing (HRIC) scheme is used for free-surface tracking. The computational results are validated using available experimental results and by ensuring that details of the flow physics based on existing knowledge are properly captured. The three-dimensional nature of the flow in the developed zone of the hydraulic jump is well demonstrated, and a better understanding of the interaction between the wall-jet flow and the roller region above it is revealed. The paper also resolves the internal turbulent structure of the classical hydraulic jump, which is not completely realized in the experimental results. Quadrant decomposition of the Reynolds shear stresses reveals that inward and outward interactions dominate the flow field. This is further ascertained by the analysis of the third-order moments of the velocity field. It is also revealed that the expanding shear layer interacts with the free surface resulting in intense undulations and breaking up of the free surface.