Modelling of pluvial floods

Transcription

1 Modelling of pluvial floods Ernest Bladé FLUMEN Institute Universitat Politècnica de Catalunya Berlin, 5th October 2016

2 Pluvial floods in Spain Snow melting - Rural Runoff - Urban

3 Pluvial floods in Spain Snow melting - Rural Runoff - Urban Barcelona 2011 Sitges 2012 Tenerife 2014 Benidrom 2015

4 FLUVIAL FLOODS

5 FLUVIAL FLOODS T Aggregated (basin scale) or distributed HYDROLOGICAL MODELLING Discharge

6 FLUVIAL FLOODS T Aggregated (basin scale) or distributed HYDROLOGICAL MODELLING Discharge Open Channel Flow Eqs 1D o 2D, River + Flood Plain HYDRAULIC MODELLING Depths (Velocities)

7 FLUVIAL FLOODS T Aggregated (basin scale) or distributed HYDROLOGICAL MODELLING Discharge Open Channel Flow Eqs 1D o 2D, River + Flood Plain HYDRAULIC MODELLING Depths (Velocities) HAZARD ASSESSMENT RISK ASSESSMENT Exposure Vulnerability DAMAGE FUNCTIONS (Materials, People)

8 FLUVIAL FLOODS PLUVIAL FLOODS T Aggregated (basin scale) or distributed HYDROLOGICAL MODELLING Discharge Open Channel Flow Eqs 1D o 2D, River + Flood Plain HYDRAULIC MODELLING Depths (Velocities) HAZARD ASSESSMENT RISK ASSESSMENT Exposure Vulnerability DAMAGE FUNCTIONS (Materials, People)

9 FLUVIAL FLOODS PLUVIAL FLOODS T HYDROLOGICAL MODELLING Aggregated (basin scale) or distributed Discharge Open Channel Flow Eqs 1D o 2D, River + Flood Plain T (or scenario) INTEGRATED HYDROLOGICAL AND HYDRAULIC MODELLING Distributed Dual Flow (Surface+Draining System) Mixed Flow (Free surface+pressure) (Discharge) Depths Velocities HYDRAULIC MODELLING Depths (Velocities) HAZARD ASSESSMENT RISK ASSESSMENT Exposure Vulnerability DAMAGE FUNCTIONS (Materials, People)

10 FLUVIAL FLOODS PLUVIAL FLOODS T HYDROLOGICAL MODELLING HYDRAULIC MODELLING Aggregated (basin scale) or distributed Discharge Open Channel Flow Eqs 1D o 2D, River + Flood Plain Depths (Velocities) T (or scenario) INTEGRATED HYDROLOGICAL AND HYDRAULIC MODELLING Distributed Dual Flow (Surface+Draining System) Mixed Flow (Free surface+pressure) (Discharge) Depths Velocities HAZARD ASSESSMENT RISK ASSESSMENT Exposure Vulnerability DAMAGE FUNCTIONS (Materials, People) HAZARD ASSESSMENT RISK ASSESSMENT Exposure Vulnerability DAMAGE FUNCTIONS PEDESTRIANS VEHICLES

11 PF Hydrology: Distributed Hydraulics: 2D Basins? Main Channel? - Dual and Mixed Flow - Inlet efficiency - Hazard criteria for pedestrians - Hazard criteria for vehicles - Global risk assessment TOOL

12 Dual and Mixed Flow Dual: combined surface-sewer flow. Mixed: combined free surface pressure flow (including trapped air)

13 Free flow Surface: Shalow Water Equations 2D Subsurface: Saint Venant Equations 1D hu hv h 0 t x v 2 h t x 2 y 2 hu hu g huv gh S S 2 h t x y 2 2 hv huv hv g gh S0y Sfy Dual and Mixed Flow I L + S 0x fx A Q t x 0 -s 2 Q Q gi 1 ga S 0 S f t x A Preissmann slot method T s ga T s a max 2 Mixed flow Full equations of free flow (idem up) and full equations of presurized flow A Q t x 0 -s 2 Q Q t t A 2 a A ga So Sf The equations are solved using the finite volumes method.

14 Dual and Mixed Flow PERFIL m m 0.50 m A Depth (m) m m m 6.00 m 7.00 m CL Depth (m) Tramo 1 Tramo 2 Tramo 3 Rejas PLANTA Distance (m) I II III A' Pozo Velocity (m/s) Distance (m) I II III Top Street Distance (m) I II III Results in sewer Depth Velocity Velocity at street

15 Inlet efficiency Surface flow collection. Hydraulic characterization of inlets, experimental tests and new empirical formulas for design. Validation of 3D CFD 3D free surface and bifasic flow

16 Inlet efficiency Determination of hydraulic efficiency of inlet systems.. E= Q collected / Q street E Q A y B A A n n n t 1 l 1 d g p L A B 0.36 p W A g total %

17 Dual flow: small basin example Digital Elevation Model

18 Intensity (mm/hr) Mesh of triangular elements Dual flow: small basin example Grates inlets ,200 1,500 1,800 2,100 2,400 2,700 3,000 3,300 3,600 Time (s)

19 Dual flow: small basin example Discretization of roofs

20 Dual flow: small basin example Subsurface subsistem Sewer and nodes properties

21 Dual flow: small basin example Surface: Maximum values

22 Dual flow: small basin example

23 Dual flow: small basin example Drainage system results

24 Pedestrian stability Buildings Pedestrians Vehicles Test protocol: 12 times every Q 35 experimental sessions

25 Pedestrian stability W*H (kg m): 78 Altura H (m): 1.50 Peso W (kg): 52 Edad (años): 24 W*H (kg m): Altura H (m): 1.61 Peso W (kg): 53 Combinación: 5 Visibilidad: Buena V[m/s]: 2.31 W*H (kg m): Altura H (m): 1.71 Peso W (kg): 68 Edad (años): 11 Combinación: 6 Visibilidad: Buena V[m/s]: 3.70 Edad (años): 24 Combinación: 6 Visibilidad: Buena V[m/s]: 3.50

26 Pedestrian stability

27 Pedestrian stability

28 Buildings Pedestrians Vehicles Vehicle stability

29 Vehicle stability 12 different vehicles Scales 1:14 and others close

30 Vehicle stability 32

31 Case Study: Badalona Mesh and depths Sewer system

32 Case Study: Badalona T=10 Hazard to pedestrians Risk to pedestrians 34

33 Case Study: Badalona T=10 Hazard to vehicles Risk to vehicles EAD=734.,323 35

34 TOOLS 2D Finite Volume numerical simulation tool for River Flow and Fluvial Processes Hydrodynamics Sediment transport Turbulence Structures (bridges, Weir, gates..) Wind Dam break Hydrological processes Dual flow Water quality Hazard Analysis Habitat suitability.. Friendly interface

35 THANKS 37

36 38