Hydrodynamics theory水動(dòng)力學(xué)參數(shù)設(shè)定

1、2水動(dòng)力學(xué)理論水動(dòng)力學(xué)理論Variables: Water level H (=Z+D) Flux in s-direction P (=HU) Flux in n-direction Q (=HV)Continuity equationMomentum equation3控制方程控制方程Dynamic 2-D Saint Venant Equations flow acceleration convective and cross-momentum pressure gradients (surface slope) bed shear stress, e.g. Manning, Manni

2、ng-Strickler, Chezy momentum dispersion, e.g. Smagorinsky coriolis force wind shear (not included, but prepared)Assumptions: shallow water hydrostatic pressure uniform density sub-critical flow no secondary circulation4地形的處理地形的處理Land value- Permanent land- Permanent water- Alternating dry/wet5空間網(wǎng)格的選

3、取空間網(wǎng)格的選取Shallow-water assumption s depth and n depth, s 3 D , depth DResolve bathymetry, typical length scale L s L/n , s L/5Resolve flow adaptation, typical length scale s /n =D*C2/2g, s xtghCr5 . 02xtE5 . 022tyDxDYX2.邊界條件 v.s. 初始條件3.水利條件 v.s. 邊界地形其他模型穩(wěn)定性要求是否滿足？1.渦粘系數(shù)：2.擴(kuò)散系數(shù)：3.邊界位置的選取（對(duì)于模型很重要?。┠Ｐ驮O(shè)置的推薦取值模型設(shè)置的推薦取值 Smagorinsky 常數(shù) 0.25-1 干濕區(qū)水深差 0.1-0.2m 擴(kuò)散系數(shù)UhDx)0 . 14 . 0(X 和水深數(shù)量級(jí)相似和水深數(shù)量級(jí)相似 X 遠(yuǎn)遠(yuǎn)大于水深遠(yuǎn)遠(yuǎn)大于水深MIKE 21模型的率定參數(shù)模型的率定參數(shù)1. 糙率 水深和流速2. 渦粘系數(shù) 流速3. （風(fēng)阻力系數(shù)） 水深和流速 4. 擴(kuò)散系數(shù) 污染物濃度變化5. 衰減系數(shù) 污染物濃度變化MIKE 21 HD典型的出錯(cuò)信息典型的出錯(cuò)信息1. One point wide open flux boundary 2. Elevation too low on