A-0---水文水动力基本原理

1、Fundamentals and Theory of Hydraulic Modelling水力模型的基本原理和理论,Juan Gutierrez (古霆欢) 边界条件 Upstream 上游 Q(t)- usual (i.e. hydrological model) H(t)- careful ! Rating curve, Q(H) - never ! Downstream 下游 Q(t)- careful ! H(t)- usual Rating curve, Q(H)- usual Internal conditions 内部条件 Drowned, Q(Hu/s, Hd/s) Crit

2、ical flow, Q(Hu/s),56,Hydraulic structures水工构筑物,57,St. Venant Equations 圣维南方程,Partial Differential Equations (PDEs)偏微分方程 Cannot be solved analytically 不能分解解 Must be solved by approximate methods 必须近似解 Continuous 连续的 but solved at discrete points in space and time但是在时间和空间的散点上解 Solved by approximate m

3、ethods;用近似法解 Finite differences : 1D solution technique in InfoWorks 有限差： InfoWorks的一维解法,58,1D vs 2D,59,2D Hydaulics,2D Flow Equations二维流量方程,60,2D Flow Solver,61,Prismatic and not prismatic links柱状连接和非柱状连接,02/10/2020,Prismatic 柱状,Non Prismatic 非柱状,Prismatic and not prismatic links柱状连接和非柱状连接,02/10/20

4、20,3D view 3D视图,Prismatic 柱状,Plan view 平面视图,Non Prismatic非柱状,River 1D-2D connection河道1D-2D连接,02/10/2020,Advantages of unstructured mesh非结构网格的特点,Page 65,Page 66,Test 4: Circular dam-break wave - initially dry bed 溃坝洪水波-干涸河床,Page 67,InfoWorks2D,Note: Distance between concentrically grey circles = 500m

5、,Page 68,A regular mesh software常规网格软件,Dry weather flows Flow survey (3 or 4 days) Pumping station / WWTW data Diurnal cycles, etc.,Storm events Flow survey (3 events) Pumping station / WWTW data Tide / river levels,Model Verification,Issues to consider Assessment of flow survey data Allocation of f

6、oul flows: locations flow rates diurnal flow profiles Infiltration / baseflows / tidal inflow Allocation of impermeable areas Soil / runoff parameters Infiltration module Modelling of ancillaries Items to compare: Flow rates Velocities Depths Volumes,Historic verification Rainfall data Flooding reco

7、rds Pumping station / WWTW data CSO spills Tide / river levels,Model Verification Review,Reporting: Model Build / Verification Report,To be based on GDSDS reporting (Phase 2),Comments on sources of data Asset survey Impermeable area survey CCTV survey Flow survey including monitor performance,Model

8、build process Use of available data Ancillaries pumping stations, CSOs, etc.,Model verification process,Verification results Graphical comparisons Tabular data Discussion key issues / model suitability,Hydraulic Assessment,Design Storm existing model Flood & surcharge frequencies,Synthetic Design St

9、orms Local rainfall parameters Range of durations Return periods,Design Storm future model Updating of model for future Flood & surcharge frequencies,Time Series existing model CSO spill frequencies & volumes,Future Model Updates Future developments & populations Proposed drainage improvements Chang

10、es to population, water usage, trade flows, etc. Climate change (see GDSDS policy),Historical Rainfall Series Choice of suitable rainfall data - synthesised if necessary (e.g. TSRSim),Time Series future model Updating of model for future CSO spill frequencies,Hydraulic Assessment Review,Hydraulic As

11、sessment Stages,Reporting: Hydraulic Assessment Report,Digital plans using MapInfo,To be based on GDSDS reporting (Phase 2 / Phase 3),Existing and future performances,Flooding & surcharging (X-X diagrams),CSO performance Spill frequencies Spill volumes PFFs at spills Formula A flows,Plan of Existing

12、 Performance,Proposed Improvement Options,Close liaison between Tobin & HRW teams,Improvements likely to include: Local repairs / rehabilitation (sewers & manholes) Upsizing of sewers New sewers Surface water separation Storage provision CSO improvements,Based on various performance deficiencies: Ex

13、cess CSO spills Flooding Structural problems Infiltration / exfiltration Service issues excess sediment, blockages,Integrated approach to improvements Deficiencies grouped (geographically) Aim to solve multiple problems,Reporting: Proposed Improvements Report,Based on GDSDS reporting style (Phase 3)

14、 Summary of existing & future needs Summary of proposed improvements Cost estimates Digital plans,Plan of ProposedImprovements,Some examples: Schematics,2020/10/2,Some examples: Schematics,2020/10/2,What to include in schematics?,2020/10/2,What are X-X diagrams?,2020/10/2,X-X diagrams,2020/10/2,2 - 50,20 -X,X -X,US node