Predicting near-field dam-break flow and impact force using a 3D model

Abstract

A three-dimensional (3D) numerical model based on the unsteady Reynolds equations was used to simulate near-field dam-break flows and estimate the impact force on obstacles. The model employs a projection method to solve the governing equations and the method of volume of fluid (VOF) to capture the water surface movement. The model is first applied to simulate two physical model experiments of dam-break flows. Model-predicted pressure, water depth and velocity distributions are compared with laboratory measurements. For the second case, the 3D-VOF model predictions are also compared with predictions made by a two-dimensional model. The 3D-VOF model is then used to calculate the impact force of dam-break flow on a steady obstacle. A physical model experiment is set up to assist the numerical model study. The model-predicted impact force on the obstacle and the critical condition for it to move are compared with the measurements from the experiment.

Keywords:

• Dam-break flow
• flume experiment
• impact force
• VOF method
• 3D model

Acknowledgement

This research was supported by the National Key Basic Research Project of China (973 Project, 2006CB403304), Tsinghua University Initiative Scientific Research Program (2009THZ07060) and the State Key Laboratory of Hydroscience and Engineering, Tsinghua University (2008-ZY-5, 2009-TC-2).