Abstract:Based on a two dimensional lattice Boltzmann method coupled with large eddy simulation(LES),a LBM-LES model combined with sediment mathematic model is proposed for 2D siltladen flows in a pumping station forebay. Shallow water equations is numerically simulated by the mesoscopic LBM-BGK(Bhatnagar Gross Krook) model and the turbulence can be taken into account and modeled efficiently by a SubGridScale stress(SGS) model. A macroscopic 2D horizontal sediment mathematic model consists of suspension transport equations, riverbed deformation equations, formula of sedimentcarrying capacity, and so on. The segregating scheme is adopted to solve the governing equations for turbulent flows and sediment governing equations,i.e., the solutions to the turbulence governing equations,suspension transport equations, and sediment erosion & deposition along the forebay bed are solved sequentially. Finally, the simulated velocity distribution is in agreement with the experimental data, and the depth distributions, the vortex position and size as well as the sediment erosiondeposition are successfully predicted in the forebay. All the calculation results agree well the hydrodynamic rules in nature. The numerical results show that this model can well reproduce the sediment laden flow patterns,sediment erosion and deposition in the forebay, and the mathematical model and numerical algorithms are accurate, reliable and feasible to predict the sediment laden flows in forebays.
唐学林, 王武昌, 王福军, 黎耀军. 泵站前池水沙流的数值模拟[J]. 排灌机械工程学报, 2011, 29(5): 411-417.
Tang Xuelin, Wang Wuchang, Wang Fujun, Li Yaojun. Numerical simulation of slitladen flows in pumping station forebay. Journal of Drainage and Irrigation Machinery Engin, 2011, 29(5): 411-417.
[1] 高传昌,王玉川,石礼文,等.泵站前池非连续挑流消能防沙技术措施[J].排灌机械工程学报,2011,29(2): 133-138.Gao Chuanchang,Wang Yuchuan,Shi Liwen,et al. Technical measure for discontinuous trajectory bucket energy dissipation and sediment prevention at forebay of pumping station[J].Journal of Drainage and Irrigation Machinery Engineering,2011,29(2): 133-138.(in Chinese)[2] 陈树容,邱 静.改善大型泵站前池水流流态的试验研究 [J].人民珠江,2006(4):15-17.Chen Shurong,Qiu Jing. Experimental study on improving flow patterns in the forebay of large pump station[J].Pearl River,2006(4):15-17.(in Chinese)[3] Constantinescu G S,Patel V C. Role of turbulence model in prediction of pumpbay vortices[J].Journal of Hydraulic Engineering,2000,126(5):387-391.[4] Yu Huidan,Girimajia S S,Luo Lishi. DNS and LES of decaying isotropic turbulence with and without frame rotation using lattice Boltzmann method[J].Journal of Computational Physics,2005,209(2):599-616.[5] Tang Xuelin,Wang Fujun,Wu Yulin. An improved large eddy simulation of twophase flows in a pump impeller[J].Acta Mechanica Sinica,2007,23(6):635-643.[6] Wang Guangqian,Wu Baosheng,Xia Junqiang. Modeling of the diversion channel closure for the third stage of the three gorges project[J].International Journal ofSediment Research,2004,19(1):75-82.[7] Zhou J G.A lattice Boltzmann model for the shallow water equations with turbulence modelling[J].International Journal of Modern Physics C, 2002, 13(8): 1135-1150[8] 韩其为.水库淤积[M].北京: 科学出版社,2003.[9] Zou Qisu,He Xiaoyi. On pressure and velocity boundary conditions for the lattice Boltzmann BGK model[J].Physics of Fluids,1997,9(6):1591-1598.