the tous case study sumacarcel flooding

The Tous Case study:mesh refinement & optimization data

J. MurilloUniversity of Zaragoza

4th (Final) IMPACT Project Workshop:Zaragoza, Spain 3-5th November 2004

The Tous case studySumacarcel flooding

Sumacarcel

Deph averaged Navier-Stokes equations

USUG

UFU

,, yxyxt

Tyx qqh ,,UT

yxxx h

qqgh

h

qq

,

2,

22

F

T

yyxy

gh

h

q

h

qqq

2,,

22

G

Tfyyfxx SSghSSgh )(),(,0 00 S

Mathematical model

Finite Volume Upwind Scheme• explicit and first-order

• upwind treatment of the source terms

• special treatment of wetting/drying boundaries.

tA

s

i

kNE

k m

nk

mmmmni

ni

d)~)~((

1

3

1

1 eαUU

Numerical model

Adapted mesh refinement

Time step and geometry

klA

ti

Adapted mesh refinement

Number of involved cells• If the number of cells increases the discrete

representation of the real problem improves.• The accuracy of the results is enhanced• Computing time grows

Computacional experiencie • Larger cells for smooth topography• Smaller cells for highly irregular topography• Optimization: Local refinement

Adapted mesh refinement

Structured meshes: refinementRefinement area

Adapted mesh refinement

Triangular mesh of variable density

Level 1 Level 2 Level 3 Level 4

Adapted mesh refinement

Adapted mesh refinement

Triangular mesh refinement: conectors

Triangular mesh refinement criteria

Z: bottom elevation

)( Z

Adapted mesh refinement

Triangular mesh refinement.

Adapted mesh refinement

Detail of the reservoir. Constant density mesh, edge 5 cm.

Adapted mesh refinement

Detail of the reservoir. Constant density mesh, edge 20 cm.

Adapted mesh refinement

Detail of the reservoir. Maximum edge lenght 20 cm. Minimum 10 cm.

Adapted mesh refinement

Constant density mesh, edge 5 cm.

Maximum edge lenght 20 cm. Minimum 10 cm.

Adapted mesh refinement

Constant density mesh, edge 5 cm.

Maximum edge lenght 40 cm. Minimum 20 cm.

Adapted mesh refinement

Detail of the reservoir. Maximum edge lenght 40 cm

Adapted mesh refinement

General view

The Tous case study

Detail of Sumacarcel. Edge 1.25 m.Number of cells: 213689

Detail of Sumacarcel. Maximum edge lenght 20 m. Minimum 5 m.Number of cells: 39231

Detail of Sumacarcel. Maximum edge lenght 20 m. Minimum 5 m.Number of cells: 39231

Computed data. Initial hydrograph.

The main conclusion is that the development of local refinement techniques is fundamental to perform flooding simulation over gross areas, where highly irregular geometries are found.If not the computing time is unacceptable. 

Thank you for your attention