NUMERICAL COMPUTATION OF TURBULENCE DEVELOPMENT IN FLOW OVER SAND DUNES
The spatial development of sub-critical, turbulent, open-channel flow over a bottom with five dunes is studied. The steady-state flow is described by the RANS equations utilizing the k-ε turbulence model. The free-surface treatment is based on the rigid-lid approximation method,while the numerical solution is based on a finite-volume discretization. The Froude number is Fr=0.3,while both smoothand rough bottom cases are considered. Mean velocity and turbulence numerical predictions are in good agreement to available experimental data and analytical expressions. Then,results are presented for the streamwise development of eddy viscosity, Reynolds stresses and turbulence production of the flow over bed with train of five fixed dunes with dune length to water depth ratio L/d=5 and dune height to water depth ratio h/d=0.25. Numerical results are compared to available experimental data and overall agreement is satisfactory. Turbulence is generated mostly by flow separation at the dune crest and does not reach an equilibrium state over the dunes.
dunes open-channel flow turbulent flow RANS equations rigid-lid method
N.Th.Fourniotis N.E.Toleris A.A.Dimas A.C.Demetracopoulos
Department of Civil Engineering, University of Patras, 26 500 Patras, Greece
国际会议
第16届亚太地区国际水利学大会暨第3届水工水力学国际研讨会(16th IAHR-APD Congress and 3rd Symoposium of IAHR-ISHS)
南京
英文
843-848
2008-10-20（万方平台首次上网日期，不代表论文的发表时间）