Three-dimensional unsteady RANS model for hydraulic jumps

Abstract

ABSTRACT Hydraulic jump is a classical problem cause due to transition of flow from supercritical state to subcritical state. In this study, application of three-dimensional unsteady Reynolds-averaged Navier stokes model for hydraulic jump is proposed. The basic equations of k – ε model and Reynolds equation are solved for three-dimensional flow field of hydraulic jump. Both the standard and non-linear form of k – ε model is considered in the simulation. The computed results are compared with the previous experimental and theoretical results. The comparisons of water surface profile showed that, more local energy dissipation is observed for the non-linear k – ε model. However, the vertical distributions of stream-wise velocities within the jump, for both the models reproduced the close agreement with the theoretical and experimental data. The pronounced effect of the non-linearity is observed in stream-wise turbulence intensity distribution, where non-linear k – ε model produced reasonable agreement with the previous theoretical data as compared to the standard k – ε model. Apart from the turbulence intensity, the non-linear k – ε model also reproduced the distribution of turbulent energy dissipation rate, within hydraulic jump effectively. Finally, it is concluded that the present study could reproduce the turbulent characteristics of hydraulic jump considerably in view of the non-linear k – ε model.