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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
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Mathematical model
Finite Volume Upwind Scheme• explicit and first-order
• upwind treatment of the source terms
• special treatment of wetting/drying boundaries.
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kNE
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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