Presentation is loading. Please wait.

Presentation is loading. Please wait.

Lumped and distributed modelling of suspended solids in a combined sewer catchment in Santiago de Compostela (Spain) R. Hermida, JOSE ANTA, M. Bermúdez,

Similar presentations


Presentation on theme: "Lumped and distributed modelling of suspended solids in a combined sewer catchment in Santiago de Compostela (Spain) R. Hermida, JOSE ANTA, M. Bermúdez,"— Presentation transcript:

1 Lumped and distributed modelling of suspended solids in a combined sewer catchment in Santiago de Compostela (Spain) R. Hermida, JOSE ANTA, M. Bermúdez, L. Cea, J. Suárez & J. Puertas GEAMA Research Team Universidade da Coruña

2 INTRODUCTION Flow and Pollution Modelling in Urban Systems
dust and dirt buildup washoff gully-pot processes sewer erosion - transport Tenemos que emplear los módiukos Polución es más compleja y modelos a veces sobreparametrizados: necesidad de saber como funcionanan los modelos 2

3 OBJETIVES Comparison of a lumped and distributed model for TSS in “El Ensanche” combined sewer catchment Model developed with Infoworks CS 9.x Ackers-White equation KUL model 10 rain event were used for model calibration. More details presented yesterday: “Mobilized pollution indicators in a combined sewer system during rain events” del Río et al. In order to gain some kno

4 DESCRIPTION OF THE URBAN CATCHMENT

5 MODEL DEVELOPMENT Distributed model (del Río, 2011)
316 subcathments: 183 streets, 128 roofs, 5 pervious areas 7 km of pipes (150 – 1200 mm) Lumped model (Hermida, 2012) DIAPO DE CRITERIO SIMPLIFICADO OTROS VALORES PARA Q=5 and 7

6 BUILDUP Model parameters : Ps, K1 Model parameters : C1, C2, C3
WHASOFF DIAPO DE CRITERIO SIMPLIFICADO OTROS VALORES PARA Q=5 and 7

7 SEWER TRANSPORT MODELS
Ackers & White (1996) Model parameter are fixed. Model variables: s, d50 KUL (Boutelegier and Berlamont, 2002) Too many model parameters (6 parameters). Model variables: s, d50 DIAPO DE CRITERIO SIMPLIFICADO OTROS VALORES PARA Q=5 and 7

8 SEWER TRANSPORT MODELS
KUL : Shields approach (Shizari and Berlamont, 2010) Shields number has to be re-evaluated in each time – step (not allowed in IF) Ota and Nalluri equation (2003) DIAPO DE CRITERIO SIMPLIFICADO OTROS VALORES PARA Q=5 and 7 KUL equation as function of s, d50

9 SENSITIVITY ANALYSIS: POLLUTION MODEL
InfoWorks doesn’t allow an easy implementation of formal MC inference Sensitivity analysis of the different Infworks quality subroutines with Matlab. Methodology proposed by Kleidorfer (2009): Local sensitivity analysis Global sensitivity analysis Graphical methods Hornberger – Spear – Young DIAPO DE CRITERIO SIMPLIFICADO OTROS VALORES PARA Q=5 and 7

10 SENSITIVITY ANALYSIS RESULTS
BUILDUP Buildup factor is more sensitivity than the decay factor Model is sensitivity to both parameters WHASOFF Model is almost insensitivity to C3 coefficient and can be neglected C2 is more sensitivity than C1 SEDIMENT TRANSPORT MODEL d50 is more sensitivity than the specific density s DIAPO DE CRITERIO SIMPLIFICADO OTROS VALORES PARA Q=5 and 7

11 MODEL CALIBRATION Hydraulic model calibration
11 rainy days: NS=0.85 Pollution model calibration Visual calibration: 3 events Model validation: 7 events Distributed model Ackers – White KUL (Ota & Nalluri) Lumped model DIAPO DE CRITERIO SIMPLIFICADO OTROS VALORES PARA Q=5 and 7

12 MODEL CALIBRATION DIAPO DE CRITERIO SIMPLIFICADO
OTROS VALORES PARA Q=5 and 7

13 CONCLUSIONS Successful application of sensitivity analysis to determine the most relevant parameters for pollution modelling in InfoWorks CS All the sensitivity tests shows similar results Lumped model works better in terms of NS and EMC Distributed model works better in terms of Cmax KUL – Ota & Nalluri approach avoids the determination of a large number of model parameters Ackers – White is more accurate than KUL approach for lumped model and viceversa.

14 THANKS FOR YOUR ATTENTION
THANKS FOR YOUR ATTENTION

15 SENSITIVITY ANALYSIS Hornberger – Spear – Young Method (Kleidorfer, 2009) MC framework Comparison of model outputs with a synthetic run with NS Analysis of the distance of behavioral (NS>0) and non behavioral (NS<0) empirical cumulative pdf Nash-Sutcliffe Synthetic run

16 BUILDUP HSY: Ps HSY: K1 DIAPO DE CRITERIO SIMPLIFICADO
OTROS VALORES PARA Q=5 and 7


Download ppt "Lumped and distributed modelling of suspended solids in a combined sewer catchment in Santiago de Compostela (Spain) R. Hermida, JOSE ANTA, M. Bermúdez,"

Similar presentations


Ads by Google