Numerical simulation of sharp-crested weir flows

Abstract

The sharp-crested weir in a rectangular open channel can be used as a simple and accurate device for flow measurement and control in open channels. However, in the past, the solution to this problem was found mainly on the basis of experimental data or through the development of simplified theoretical expressions. In the present study, k-ε turbulence model is applied to obtain the flow parameters such as pressure head distributions, velocity distributions, and water surface profiles. The predictions of the proposed numerical model are validated using existing experimental data. The k-ε turbulence model developed is used to predict the characteristics of a sharp-crested weir in a rectangular open channel. The volume of fluid (VOF) scheme is used to find the shape of the free surface. A properly validated model permits one to obtain the flow characteristics of the sharp-crested weir for a wide range of weir and hydraulic parameters without recourse to expensive and more time consuming experimental methods. Further, the model permits one to incorporate small changes in the geometric parameters involving small changes in inlet and outlet conditions and study their impact on the weir flow characteristics.

Computational fluid dynamics of vortex flow controls at low flow rates

“…The results of the simulations were validated using experimental data of surface profiles, distributions of velocities and pressure heads. Qu et al (2009) concluded that the velocity and pressure head distributions in the nappe region were in very good agreement with the experimental results. The surface profiles of the simulation also agreed with the experimental profiles.…”

“…Similarly, Qu et al (2009) reported the two-dimensional (2D) numerical simulation of sharp-crested weir flows in a rectangular open channel. The standard two-equation Wilcox k-ø turbulence model was adopted for the numerical simulation of turbulence and, again, the VOF method was utilised to capture the free surface between air and water.…”

“…Previous research (e.g. Ferrari, 2010;Qu et al, 2009;Sarker and Rhodes, 2004) has demonstrated the accuracy of the k-å turbulence model to predict the turbulence of sharpcrested weirs in open channels. Applying an ensemble average to the Navier-Stokes equations for incompressible flow produces the RANS equations…”

SPH simulation of free surface flow over a sharp-crested weir

“…Very recently, a new research work has appeared [16], the only one (to the knowledge of the author) that has published numerical results on sharp-crested weir flow. In [16] the two-dimensional incompressible Navier-Stokes equations have been solved using the volume of fluid (VOF) method of Hirt and Nichols [11].…”

Analysis of Simulation Outputs for the Mutual Effect of Flow in Weir and Gate System

“…Modelling of flow over sharp weir and validation has been carried on by numerous investigations. A good agreement had found between simulation of weir flow and carried a comparison of flow properties such as pressure head, distribution of velocity, and water surface profiles with that of experimental data by employing k-ε turbulence model [1]. Following the method of Zhao and Tai for finite volume numerical hybrid level discretizations, Lv et al [2] were able to study the flow over sharp and broad weirs for validation of that numerical schemes.…”