894 J Lake Sci km m m 2933 km m 21 d 1 Fig 1 The water system of Lake Poyang and main monitoring

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1 J Lake Sci http //www jlakes org jlakes@niglas accn 2011 by Journal of Lake Sciences * HLLC Two-dimensional numerical simulation of hydrodynamic and pollutant transport for Lake Poyang LAI Xijun JIANG Jiahu HUANG Qun & XU Ligang State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing P R China Abstract The present study aims to develop a mathematical model for analyzing and predicting the hydrodynamic and water quality in one large lake Lake Poyang with great and rapid stage fluctuation the complex topography and geometry the complicated connectivity of narrow channels and depressions inside the lake the frequently switch between exposed grass beach and water Based on the two-dimensional shallow water equations and pollutant transport equations the coupled two-dimensional hydrodynamic and pollutant transport model is developed The unstructured finite volume method is applied to discretize the equations The normal water mass momentum and pollutant fluxes are computed by the HLLC solver The water front moving boundary is identified automatically by the judgment of the latest water stage It makes the model be capable of simulating the complex flow regime and the dynamic of pollutant transport in the lake with drying and wetting processes The hydrodynamic model is calibrated by the water regime of the year 1998 Based on the calibrated hydraulic parameters the hydrodynamic and water quality COD Mn and ammonia from January to October in 2008 are simulated by the proposed model The time series data of measured water stage COD Mn and ammonia and remotely water extent of CBERS data are both used to validate the results of computation in time and space The results indicate that the model has the capability to model the flows dynamic and the pollutant transport in this kind of lake Keywords Hydrodynamics water quality mathematical model unstructured grids Lake Poyang 1 Princeton ocean 2 - model 3 * KZCX1 - YW xjlai@ niglas ac cn

894 J Lake Sci 2011 23 6 20 4-8 1 16 2 10 4 km 2 8 91-14 04 m 21 69 m 2933 km 2 5 1 m 21 d 1 Fig

2 894 J Lake Sci km m m 2933 km m 21 d 1 Fig 1 The water system of Lake Poyang and main monitoring stations for water quality WASP

3 U = U t h hu F hv x = hφ + F U = S 1 hu hu 2 huv huφ + gh2 2 F y = hv huv hv 2 hvφ + gh2 2 0 gh S 0x - S fx + 2 ε ρ hu + c ρ a w ω 2 sin α + fvh ρ 2 S = gh S 0y - S fy + 2 ε ρ hv + c ρ a w ω 2 cos α - fuh ρ 2 x ( D φxh φ x ) + y ( D φyh φ y ) - K φhφ + Sφ h u v x y φ COD Mn F x x F y y S S 0x = - z b x x S 0y = - z b y y S fx = ρn 2 h u 槡 u 2 + v 2 x S fy = ρn 2 h v 槡 u 2 + v 2 y c w ρ a ω α y D φx D φy x y K φ φ S φ V A t V UdV = - A F U nda + V SdV 2 n A F φ n U n +1 = U n - Δt T θ -1 F ΔV Σm j U A j + Δt S 3 j = 1 ΔV m A j j S j F n j = F j U n x' - y'

896 J Lake Sci 2011 23 6 x' U t + F U = 0 4 x U x 0 = U L x < 0 { U R x > 0 5 x' n 2 U q U L U R U t = 0 t = 0 + x' = 0 F LR = F U L U R x - y HLLC 9 F LR 2 Fig 2 Cell of finite volume method F HLLC

4 896 J Lake Sci x' U t + F U = 0 4 x U x 0 = U L x < 0 { U R x > 0 5 x' n 2 U q U L U R U t = 0 t = 0 + x' = 0 F LR = F U L U R x - y HLLC 9 F LR 2 Fig 2 Cell of finite volume method F HLLC LR = { F L 0 S L F L + S L U * L - U L S L 0 S * F R + S R U * R - U R S * 0 S R F R S R 0 6 S S L S * S R Roe 16 L - U L U * L = h L 1 S S L - S * v L * φ L T U * R U L U R 11 Neumann L R 8 3 3a - 3d h L > ε a h R < Z bl + ε b h R > Z bl + ε h L < ε c h R < Z bl + ε d h R > Z bl + ε 3e - 3h 2 2 1

897 3 Fig 3 Possible water depth across cell interface 4 9877

5 897 3 Fig 3 Possible water depth across cell interface m 2000 m Fig 4 Computational grids Neumann

6 898 J Lake Sci n n = n 0 h α n 0 1 m h α 1998 n 0 = α = - 1 /6 5 Nash Fig 5 The calibration of hydrodynamic model of Lake Poyang ε m COD Mn COD Mn d

7 899 6 Fig 6 The stage comparison between computation circle and measurements line in main stations of Lake Poyang CBERS CCD 113 km 20 m m 7 CBERS COD Mn 8 COD Mn COD Mn COD Mn COD Mn mg /L 6

900 J Lake Sci 2011 23 6 7 Fig 7 Comparison of the computed left and remotely

8 900 J Lake Sci Fig 7 Comparison of the computed left and remotely observed water extent right at different time instants COD Mn 9 4 HLLC

9 901 8 COD Mn Fig 8 Comparison of computed and measured COD Mn and ammonia concentrations in the main stations of Lake Poyang

902 J Lake Sci 2011 23 6 9 COD Mn Fig 9 Spatial distribution of COD Mn in Lake Poyang at different time instants 5 1 Jorgensen SE L ffler H Rast W Lake and reservoir management Elsevier Science Ltd

10 902 J Lake Sci COD Mn Fig 9 Spatial distribution of COD Mn in Lake Poyang at different time instants 5 1 Jorgensen SE L ffler H Rast W Lake and reservoir management Elsevier Science Ltd Huang A Rao YR Lu Y Evaluation of a 3-D hydrodynamic model and atmospheric forecast forcing using observations in Lake Ontario Journal of Geophysical Research Beletsky D Schwab D McCormick M Modeling the summer circulation and thermal structure in Lake Michigan Journal of Geophysical Research Ⅱ Hu W J rgensen SE Zhang F A vertical-compressed three-dimensional ecological model in Lake Taihu China Ecological Modelling Toro EF Shock-capturing methods for free-surface shallow flows John Wiley and Sons Zhao DH Shen HW Tabios III GQ et al Finite volume two-dimensional unsteady flow model for river basins Journal of Hydraulic Engineering Einfeldt B On godunov-type methods for gas dynamics SIAM Journal on Numerical Analysis

Microsoft Word - 刘慧板.doc

Microsoft Word - 刘慧板.doc 中国环境科学 2012,32(5):933~941 China Environmental Science 系统动力学在空港区域规划环境影响评价中的应用刘慧 1,2, 郭怀成 1*, 盛虎 1, 都小尚 1,3, 李娜 1 1, 杨永辉 (1. 北京大学环境科学与工程学院, 北京 100871; 2.