Three-Dimensional Numerical Model for Flow and Bed Deformation around River Hydraulic Structures |
| |
Authors: | Nobuhisa Nagata Takashi Hosoda Tatsuaki Nakato Yoshio Muramoto |
| |
Affiliation: | 1Deceased December 2000; formerly, Research Associate, Dept. of Civil Engineering, Kyoto Univ., Yoshida, Sakyo-Ku, Kyoto 606-8501, Japan. 2Professor, Dept. of Civil Engineering, Kyoto Univ., Yoshida, Sakyo-Ku, Kyoto 606-8501, Japan. E-mail: hosoda@river4.kuciv.kyoto-u.ac.jp 3Research Engineer, IIHR–Hydroscience & Engineering; formerly, Iowa Institute of Hydraulic Research; and Adjunct Professor, Dept. of Civil and Environmental Engineering, Univ. of Iowa, Iowa City, IA 52242. E-mail: tatsuaki-nakato@uiowa.edu 4Professor Emeritus, Kyoto Univ.; Research Institute of Osaka, Foundation of River and Watershed Environment Management, 1-6-4 Ohtemae, Chuo-Ku, Osaka 540-0008, Japan. E-mail: muramoto-y@osaka.kasen.or.jp
|
| |
Abstract: | This paper describes a numerical model developed to simulate flow and bed deformation around river hydraulic structures. The model solved the fully three-dimensional, Reynolds-averaged Navier–Stokes equation expressed in a moving boundary-fitted coordinate system to calculate the flow field with water and bed surfaces varying in time. A nonlinear k-ε turbulence model was employed in order to predict flow near the structure where three-dimensional flow is dominant. The temporal change in bed topography was calculated by coupling a stochastic model for sediment pickup and deposition using a momentum equation of sediment particles in order to account for the effect of nonequilibrium sediment transport. In validating the numerical model, a spur dike and a bridge pier, which are considered to be typical river-engineering structures, were selected. By comparing the numerical results with observed laboratory experimental data, the model was found to reproduce flow and scour geometry around these structures with sufficient accuracy. |
| |
Keywords: | Numerical analysis Scour Dikes Bridges Piers Three-dimensional models Hydraulic structures Rivers |
|
|