Recent advances on numerical simulation in coastal oceanography

May 19, 2017 - −gh∂y z.... Application field : some examples. Coastal hydrodynamic .... [Greenberg, Leroux, 1996] , [Gosse, Leroux , 1996] scalar case.
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SHARK-FV Arnaud Duran

Recent advances on numerical simulation in coastal oceanography

Shallow Water Equations Generalities dG discretization Extension to dispersive equations

Arnaud Duran Institut Camille Jordan - Université Claude Bernard Lyon 1

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Work in collaboration with F. Marche (IMAG Montpellier)

SHARK-FV 2017 Conference - Ofir, May 19.

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

1 / 23

Outline SHARK-FV Arnaud Duran

1

Shallow Water Equations - Generalities

Shallow Water Equations Generalities dG discretization

2

dG discretization

3

Extension to dispersive equations

Handling breaking waves (work with G. Richard)

4

Handling breaking waves (work with G. Richard)

Numerical validations

5

Perspectives

Extension to dispersive equations

Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

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Outline SHARK-FV Arnaud Duran

1

Shallow Water Equations - Generalities Introduction Numerical stability criteria Reformulation of the SW equations

Shallow Water Equations Generalities Introduction Numerical stability criteria Reformulation of the SW equations

2

dG discretization

3

Extension to dispersive equations

Extension to dispersive equations

4

Handling breaking waves (work with G. Richard)

Handling breaking waves (work with G. Richard)

5

Perspectives

Numerical validations

dG discretization

Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

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Shallow Water Equations SHARK-FV

2D Formulation

Arnaud Duran

∂t U + ∇.G (U) = B(U, z) .







hu

h 1 2 2    U = hu  , G (U) =  2 gh + hu  hv huv

hv







0      , B(U, z) = −gh∂x z   1 2 −gh∂y z gh + hv 2 2 huv

Introduction Numerical stability criteria Reformulation of the SW equations dG discretization Extension to dispersive equations

Application field : some examples

Handling breaking waves (work with G. Richard)

Coastal hydrodynamic

Arnaud Duran (ICJ)

Shallow Water Equations Generalities

SHARK-FV

Numerical validations Perspectives

19/05/2017

4 / 23

Shallow Water Equations SHARK-FV

2D Formulation

Arnaud Duran

∂t U + ∇.G (U) = B(U, z) .







hu

h 1 2 2    U = hu  , G (U) =  2 gh + hu  hv huv

hv







0      , B(U, z) = −gh∂x z   1 2 −gh∂y z gh + hv 2 2 huv

Introduction Numerical stability criteria Reformulation of the SW equations dG discretization Extension to dispersive equations

Application field : some examples

Handling breaking waves (work with G. Richard)

Coastal hydrodynamic

Arnaud Duran (ICJ)

Shallow Water Equations Generalities

SHARK-FV

Numerical validations Perspectives

19/05/2017

4 / 23

Shallow Water Equations SHARK-FV

2D Formulation

Arnaud Duran

∂t U + ∇.G (U) = B(U, z) .







hu

h 1 2 2    U = hu  , G (U) =  2 gh + hu  hv huv

hv







0      , B(U, z) = −gh∂x z   1 2 −gh∂y z gh + hv 2 2 huv

Introduction Numerical stability criteria Reformulation of the SW equations dG discretization Extension to dispersive equations

Application field : some examples

Handling breaking waves (work with G. Richard)

Coastal hydrodynamic

Arnaud Duran (ICJ)

Shallow Water Equations Generalities

SHARK-FV

Numerical validations Perspectives

19/05/2017

4 / 23

Shallow Water Equations SHARK-FV

2D Formulation

Arnaud Duran

∂t U + ∇.G (U) = B(U, z) .







hu

h 1 2 2    U = hu  , G (U) =  2 gh + hu  hv huv

hv







0      , B(U, z) = −gh∂x z   1 2 −gh∂y z gh + hv 2 2 huv

Introduction Numerical stability criteria Reformulation of the SW equations dG discretization Extension to dispersive equations

Application field : some examples

Handling breaking waves (work with G. Richard)

Coastal hydrodynamic

Arnaud Duran (ICJ)

Shallow Water Equations Generalities

SHARK-FV

Numerical validations Perspectives

19/05/2017

4 / 23

Shallow Water Equations SHARK-FV

2D Formulation

Arnaud Duran

∂t U + ∇.G (U) = B(U, z) .







hu

h 1 2 2    U = hu  , G (U) =  2 gh + hu  hv huv

hv



Shallow Water Equations Generalities





0      , B(U, z) = −gh∂x z   1 2 −gh∂y z gh + hv 2 2 huv

Introduction Numerical stability criteria Reformulation of the SW equations dG discretization Extension to dispersive equations

Application field : some examples

Handling breaking waves (work with G. Richard) Numerical validations

Tsunamis

Arnaud Duran (ICJ)

SHARK-FV

Perspectives

19/05/2017

4 / 23

Shallow Water Equations SHARK-FV

2D Formulation

Arnaud Duran

∂t U + ∇.G (U) = B(U, z) .







hu

h 1 2 2    U = hu  , G (U) =  2 gh + hu  hv huv

hv







0      , B(U, z) = −gh∂x z   1 2 −gh∂y z gh + hv 2 2 huv

Introduction Numerical stability criteria Reformulation of the SW equations dG discretization Extension to dispersive equations

Application field : some examples

Handling breaking waves (work with G. Richard)

Rivers, dam breaks

Arnaud Duran (ICJ)

Shallow Water Equations Generalities

SHARK-FV

Numerical validations Perspectives

19/05/2017

4 / 23

Numerical issues SHARK-FV

Stability criteria

Arnaud Duran

Preservation of steady states : → (C-property) [Bermudez & Vázquez, 1994]

Shallow Water Equations Generalities Introduction Numerical stability criteria Reformulation of the SW equations

h + z = cte , u = 0 . Robustness : preservation of the water depth positivity.

dG discretization

Entropy inequalities. Notable advances : . [Greenberg, Leroux, 1996] , [Gosse, Leroux , 1996] scalar case . [Garcia-Navarro, Vázquez-Cendón , 1997] , [Castro, Gonzales, Pares, 2006] Roe schemes, [LeVeque, 1998] wave-propagation algorithm . [Perthame, Simeoni, 2001] , [Perthame, Simeoni, 2003] kinetic schemes . [Gallouët, Hérard, Seguin, 2003] , [Berthon, Marche, 2008] VFRoe schemes . [Audusse et al, 2004] Hydrostatic Reconstruction, [Ricchiuto et al, 2007] RD schemes , [Lukácová-Medvidová, Noelle, Kraft, 2007] FVEG schemes, [Xing, Zhang, Shu, 2010] , [Berthon, Chalons, 2016] ... Arnaud Duran (ICJ)

SHARK-FV

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

5 / 23

Reformulation of the SW equations SHARK-FV Arnaud Duran Shallow Water Equations Generalities Introduction Numerical stability criteria Reformulation of the SW equations

1D Configuration h

u

dG discretization Extension to dispersive equations

z

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

6 / 23

Reformulation of the SW equations SHARK-FV Arnaud Duran Shallow Water Equations Generalities Introduction Numerical stability criteria Reformulation of the SW equations

1D Lake at rest configuration

dG discretization

h z

η = cte

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

6 / 23

Reformulation of the SW equations SHARK-FV Arnaud Duran Shallow Water Equations Generalities

1D Lake at rest configuration

Introduction Numerical stability criteria Reformulation of the SW equations

h z

dG discretization

η = cte

First works : . [Zhou, Causon, Mingham, 2001] Surface Gradient Method . [Rogers, Fujihara, Borthwick, 2001] , [Russo, 2005] , [Xing, Shu, 2005]

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

6 / 23

Reformulation of the SW equations SHARK-FV Arnaud Duran Shallow Water Equations Generalities

1D Lake at rest configuration

Introduction Numerical stability criteria Reformulation of the SW equations

h z

dG discretization

η = cte

First works : . [Zhou, Causon, Mingham, 2001] Surface Gradient Method . [Rogers, Fujihara, Borthwick, 2001] , [Russo, 2005] , [Xing, Shu, 2005] . [Liang, Borthwick, 2009] , [Liang, Marche, 2009] “Pre-Balanced” formulation.

Arnaud Duran (ICJ)

SHARK-FV

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

6 / 23

Reformulation of the SW equations SHARK-FV

1D Lake at rest configuration

Arnaud Duran Shallow Water Equations Generalities

h z

Introduction Numerical stability criteria Reformulation of the SW equations

η = cte

dG discretization

Pre balanced formulation

Extension to dispersive equations

∂t V + ∇.H(V , z) = S(V , z) . 







η hu hv     V = hu  , H(V , z) =  12 g (η 2 − 2ηz) + hu 2 huv . 2 2 1 huv hv g (η − 2ηz) + hv 2   0   Topography source term : S(V , z) = −g η∂x z  . −g η∂y z Arnaud Duran (ICJ)

SHARK-FV

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

6 / 23

Outline SHARK-FV Arnaud Duran

1

Shallow Water Equations - Generalities

2

dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity

3

Extension to dispersive equations

Extension to dispersive equations

4

Handling breaking waves (work with G. Richard)

Handling breaking waves (work with G. Richard)

5

Perspectives

Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

7 / 23

dG method : general background SHARK-FV

Pd (T ) := {2 variables polynomials on

Arnaud Duran

T of degree at most d} . Shallow Water Equations Generalities

Vh := {v ∈ L2 (Ω) | ∀T ∈ Th , v|T ∈ Pd (T )}. Approximate solution : Vh (x, t) =

Nd X

dG discretization

Vl (t)θl (x) ,

l=1

Local weak formulation (1) ∂t V + ∇.H(V , z) = S(V , z)

∀x ∈ T .

dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

8 / 23

dG method : general background SHARK-FV

Pd (T ) := {2 variables polynomials on

Arnaud Duran

T of degree at most d} . Shallow Water Equations Generalities

Vh := {v ∈ L2 (Ω) | ∀T ∈ Th , v|T ∈ Pd (T )}. Approximate solution : Vh (x, t) =

Nd X

dG discretization

Vl (t)θl (x) ,

l=1

Local weak formulation (2) ∂t V φh (x) + ∇.H(V , z)φh (x) = S(V , z)φh (x)

∀x ∈ T .

dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

8 / 23

dG method : general background SHARK-FV

Pd (T ) := {2 variables polynomials on

Arnaud Duran

T of degree at most d} . Shallow Water Equations Generalities

Vh := {v ∈ L2 (Ω) | ∀T ∈ Th , v|T ∈ Pd (T )}. Approximate solution : Vh (x, t) =

Nd X

dG discretization

Vl (t)θl (x) ,

∀x ∈ T .

l=1

Local weak formulation (3) Z

Z ∇.H(V , z)φh (x)dx =

∂t V φh (x)dx + T

Z

T

S(V , z)φh (x)dx T

dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

8 / 23

dG method : general background SHARK-FV

Pd (T ) := {2 variables polynomials on

Arnaud Duran

T of degree at most d} . Shallow Water Equations Generalities

Vh := {v ∈ L2 (Ω) | ∀T ∈ Th , v|T ∈ Pd (T )}. Approximate solution : Vh (x, t) =

Nd X

dG discretization

Vl (t)θl (x) ,

dG method : generalities Numerical fluxes Preservation of the water depth positivity

∀x ∈ T .

l=1

Local weak formulation (4) Z ∂t V φh (x)dx + T

Z T

Z

R T

∇.H(V , z)φh (x)dx =

S(V , z)φh (x)dx T

@ R @ ∂t V φh (x)dx − H(V , z).∇φh (x)dx + T Z Z H(V , z).~ nφh (s)ds = S(V , z)φh (x)dx Z

∂T

Arnaud Duran (ICJ)

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

T

SHARK-FV

19/05/2017

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dG method : general background SHARK-FV

Pd (T ) := {2 variables polynomials on T of degree at most d} .

Arnaud Duran Shallow Water Equations Generalities

Vh := {v ∈ L2 (Ω) | ∀T ∈ Th , v|T ∈ Pd (T )}. Approximate solution : Vh (x, t) =

Nd X

dG discretization

Vl (t)θl (x) ,

∀x ∈ T .

l=1

Through a semi-discrete formulation (1)

Extension to dispersive equations

• V → Vh Z ∂t T

dG method : generalities Numerical fluxes Preservation of the water depth positivity

Nd X

Z  Vl (t)θl (x) φh (x)dx − H(Vh , zh ).∇φh (x)dx + T

l=1

Z

Z H(Vh , zh ).~ nφh (s)ds =

∂T

Arnaud Duran (ICJ)

S(Vh , zh )φh (x)dx

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

T

SHARK-FV

19/05/2017

8 / 23

dG method : general background SHARK-FV

Pd (T ) := {2 variables polynomials on T of degree at most d} .

Arnaud Duran Shallow Water Equations Generalities

Vh := {v ∈ L2 (Ω) | ∀T ∈ Th , v|T ∈ Pd (T )}. Approximate solution : Vh (x, t) =

Nd X

dG discretization

Vl (t)θl (x) ,

∀x ∈ T .

l=1

Through a semi-discrete formulation (2) • V → Vh • φh → θ j Z Z Nd X  Vl (t)θl (x) θj (x)dx − H(Vh , zh ).∇θj (x)dx + ∂t T

T

l=1

Z

Z H(Vh , zh ).~ nθj (s)ds =

∂T

Arnaud Duran (ICJ)

S(Vh , zh )θj (x)dx

dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

T

SHARK-FV

19/05/2017

8 / 23

dG method : general background SHARK-FV

Pd (T ) := {2 variables polynomials on

Arnaud Duran

T of degree at most d} .

Shallow Water Equations Generalities

Vh := {v ∈ L2 (Ω) | ∀T ∈ Th , v|T ∈ Pd (T )}. Approximate solution : Vh (x, t) =

Nd X

dG discretization

Vl (t)θl (x) ,

∀x ∈ T .

l=1

Through a semi-discrete formulation • V → Vh • φh → θ j Z Z Nd  X ∂t Vl (t)θl (x) θj (x)dx − H(Vh , zh ).∇θj (x)dx + T

k=1

T

l=1

3 Z X

H(Vh , zh ).~ nij(k) θj (s)ds =

Arnaud Duran (ICJ)

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations

Z

Γij(k)

dG method : generalities Numerical fluxes Preservation of the water depth positivity

Perspectives

S(Vh , zh )θj (x)dx T

SHARK-FV

19/05/2017

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Numerical fluxes SHARK-FV Arnaud Duran Shallow Water Equations Generalities

Contributions on the edges

dG discretization

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes SHARK-FV Arnaud Duran Shallow Water Equations Generalities

Contributions on the edges

dG discretization

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes SHARK-FV

Contributions on the edges

Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes SHARK-FV

Contributions on the edges

Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations

VF

Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes SHARK-FV

Contributions on the edges

Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard)

DG

Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes Contributions on the edges

SHARK-FV Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

VF Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes Contributions on the edges

SHARK-FV Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

VF Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes Contributions on the edges

SHARK-FV Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

VF

DG Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes Contributions on the edges

SHARK-FV Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

VF

DG Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Numerical fluxes Contributions on the edges

SHARK-FV Arnaud Duran

Z H(Vh , zh ).~ nij(k) θj (s)ds . Γij(k)

H(Vh , zh ).~ nij(k) ≈ Hij(k) = H(V˘k− , V˘k+ , z˘k , z˘k , n~ij(k) ) .

Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

VF DG → Preservation of the motionless steady states. Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

9 / 23

Preservation of the water depth positivity SHARK-FV Arnaud Duran Shallow Water Equations Generalities dG discretization

dG schemes and maximum principle [X. Zhang, C.-W. Shu, 2010] Maximum-principle-satisfying high order schemes - 1d and 2d structured meshes [Y. Xing, X. Zhang, C.-W. Shu, 2010] Application to 1d SW [Y. Xing, X. Zhang, 2013] Extension to triangular meshes

dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

10 / 23

Preservation of the water depth positivity dG schemes and maximum principle [X. Zhang, C.-W. Shu, 2010] Maximum-principle-satisfying high order schemes - 1d and 2d structured meshes [Y. Xing, X. Zhang, C.-W. Shu, 2010] Application to 1d SW [Y. Xing, X. Zhang, 2013] Extension to triangular meshes

The method relies on a special quadrature rule.

SHARK-FV Arnaud Duran Shallow Water Equations Generalities dG discretization dG method : generalities Numerical fluxes Preservation of the water depth positivity Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations

Figure: Nodes locations for the special quadrature - P2 and P3

Perspectives

reduces to the study of a convex combination of first order Finite Volume schemes. Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

10 / 23

Outline SHARK-FV Arnaud Duran

1

Shallow Water Equations - Generalities

Shallow Water Equations Generalities

2

dG discretization

dG discretization

3

Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives

Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives

4

Handling breaking waves (work with G. Richard)

5

Perspectives

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

11 / 23

Interest of dispersive equations SHARK-FV

Objective

Arnaud Duran

Extend the range of applicability of the computations at coast. . Describe the non-linearities before the breaking point. . Dispersive equations : O(µ2 )-accurate Shallow Water equations : O(µ)-accurate .

Shallowness parameter : µ =

h02 . λ20

Shallow Water Equations Generalities dG discretization Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Dispersive equations

Arnaud Duran (ICJ)

Shallow Water

SHARK-FV

19/05/2017

12 / 23

Interest of dispersive equations Numerical issues

SHARK-FV

. Non conservative terms, high order derivatives, wave-breaking, non linearities. . Maintain the stability of the method (positivity, well balancing), even on unstructured environments.

Arnaud Duran Shallow Water Equations Generalities dG discretization Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives

Dispersive equations

Shallow Water

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

12 / 23

Interest of dispersive equations Numerical issues

SHARK-FV

. Non conservative terms, high order derivatives, wave-breaking, non linearities. . Maintain the stability of the method (positivity, well balancing), even on unstructured environments.

Arnaud Duran Shallow Water Equations Generalities dG discretization Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives

Dispersive equations

Handling breaking waves (work with G. Richard)

Shallow Water

State of the art

Numerical validations

. 1d works : [Antunes Do Carmo et al] (FD, 1993), [Cienfuegos et al] (FV, 2006), [Dutykh et al] (FV, 2013), [Panda et al] (dG, 2014), [AD, Marche] (dG, 2015) . 2d works : [Marche, Lannes] (Hybrid FV/FD, cartésien, 2015), [Popinet] (Hybrid FV/FD, cartésien, 2015) . Unstructured meshes : Weakly non linear models (Boussinesq - type ). [Kazolea, Delis, Synolakis] (FV, 2014), [Filippini, Kazolea, Ricchiuto] (Hybrid FV/FE, 2016) Arnaud Duran (ICJ)

SHARK-FV

Perspectives

19/05/2017

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Model presentation . . . .

[P. Bonneton et al, 2011] 1d derivation and optimized model. Hybrid method. [F. Chazel, D. Lannes, F. Marche, 2011] 3 parameters model

[M. Tissier et al, 2012] Wave breaking issues [D. Lannes, F. Marche, 2015] A new class of fully nonlinear and weakly dispersive Green-Naghdi models for efficient 2D simulations

SHARK-FV Arnaud Duran Shallow Water Equations Generalities dG discretization Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives Handling breaking waves (work with G. Richard)

Revoke the time dependency

Numerical validations

 ∂t η + ∂x (hu)= 0 ,       1 + αT[hb ] ∂t hu + ∂x (hu 2 ) + α−1 gh∂x η + α1 gh∂x η α     −1   + h Q1 (u) + g Q2 (η) + g Q3 1 + αT[hb ] (gh∂x η) = 0 . Arnaud Duran (ICJ)

SHARK-FV

Perspectives

19/05/2017

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Model presentation . [D. Lannes, F. Marche, 2015] A new class of fully nonlinear and weakly dispersive Green-Naghdi models for efficient 2D simulations

SHARK-FV Arnaud Duran Shallow Water Equations Generalities dG discretization Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives

Revoke the time dependency  ∂t η + ∂x (hu)= 0 ,       1 + αT[hb ] ∂t hu + ∂x (hu 2 ) + α−1 gh∂x η + α1 gh∂x η α     −1   + h Q1 (u) + g Q2 (η) + g Q3 1 + αT[hb ] (gh∂x η) = 0 . w  h3 2  w  ∂x − h2 ∂x h∂x , hb = h0 − z , 3 h h : non linear, non conservative terms with second order derivatives.

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

. T[h]w = − . Qi=1,2,3

. 2d version : "diagonal" sytem : no coupling between u and v ! Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

13 / 23

Isolation of the hyperbolic part SHARK-FV

A convenient formulation

Arnaud Duran

∂t U + ∂x G (U) = B(U, z) + D(U, z)

Shallow Water Equations Generalities dG discretization Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

14 / 23

Isolation of the hyperbolic part SHARK-FV

A convenient formulation

Arnaud Duran

∂t U + ∂x G (U) = B(U, z) +D(U, z) {z } |

Shallow Water Equations Generalities

Shallow Water

dG discretization

. Shallow Water equations : !   hu h U= , G (U) = 1 2 hu gh + hu 2 2

Extension to dispersive equations

 ,

B(U) =

0 −gh∂x z

 .

Motivations The physical model Reformulation of the system High order derivatives Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

14 / 23

Isolation of the hyperbolic part SHARK-FV

A convenient formulation

Arnaud Duran

∂t U + ∂x G (U) = B(U, z) + | {z } Shallow Water

D(U, z) | {z }

Shallow Water Equations Generalities

Dispersive terms

dG discretization

. Shallow Water equations :  U=

h hu

 ,

G (U) =

hu 1 2 gh + hu 2 2

!

 ,

B(U) =

0 −gh∂x z

. Dispersive terms :   0 D(V , z) = , with Dhu (V , z)  −1  1  Dhu (V , z) = 1 + αT[hb ] gh∂x η + h Q1 (u) + g Q2 (η) α  −1  1 + g Q3 1 + αT[hb ] (gh∂x η) − gh∂x η . α Arnaud Duran (ICJ)

SHARK-FV

Extension to dispersive equations

 .

Motivations The physical model Reformulation of the system High order derivatives Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

14 / 23

Isolation of the hyperbolic part SHARK-FV Arnaud Duran

A convenient formulation ∂t U + ∂x G (U) = B(U, z) + | {z } Shallow Water

D(U, z) | {z }

Dispersive terms

Shallow Water Equations Generalities dG discretization Extension to dispersive equations

Hyperbolic part : ok

Motivations The physical model Reformulation of the system High order derivatives

Dispersive part : Dh (x, t) =

Nd X

Dl (t)θl (x) , x ∈ Ci .

l=1

Well balancing and robustness , Treatment of the second order derivatives .

Arnaud Duran (ICJ)

SHARK-FV

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

14 / 23

Isolation of the hyperbolic part SHARK-FV Arnaud Duran

A convenient formulation ∂t U + ∂x G (U) = B(U, z) + | {z } Shallow Water

D(U, z) | {z }

Dispersive terms

Shallow Water Equations Generalities dG discretization Extension to dispersive equations

Hyperbolic part : ok

Motivations The physical model Reformulation of the system High order derivatives

Dispersive part : Dh (x, t) =

Nd X

Dl (t)θl (x) , x ∈ Ci .

l=1

Well balancing and robustness , Treatment of the second order derivatives .

Arnaud Duran (ICJ)

SHARK-FV

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

14 / 23

Isolation of the hyperbolic part SHARK-FV Arnaud Duran

A convenient formulation ∂t U + ∂x G (U) = B(U, z) + | {z } Shallow Water

D(U, z) | {z }

Dispersive terms

Shallow Water Equations Generalities dG discretization Extension to dispersive equations

Hyperbolic part : ok

Motivations The physical model Reformulation of the system High order derivatives

Dispersive part : Dh (x, t) =

Nd X

Dl (t)θl (x) , x ∈ Ci .

l=1

Well balancing and robustness , Treatment of the second order derivatives .

Arnaud Duran (ICJ)

SHARK-FV

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

14 / 23

Isolation of the hyperbolic part SHARK-FV Arnaud Duran

A convenient formulation ∂t U + ∂x G (U) = B(U, z) + | {z } Shallow Water

D(U, z) | {z }

Dispersive terms

Shallow Water Equations Generalities dG discretization Extension to dispersive equations

Hyperbolic part : ok

Motivations The physical model Reformulation of the system High order derivatives

Dispersive part : Dh (x, t) =

Nd X

Dl (t)θl (x) , x ∈ Ci .

l=1

Well balancing and robustness , Treatment of the second order derivatives .

Arnaud Duran (ICJ)

SHARK-FV

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

14 / 23

LDG formalism SHARK-FV

Simplified case : T = ∂x 2

Arnaud Duran

Consider the second order ODE : f − ∂x2 u = 0 . (1) reduces to a coupled system of first order equations. f + ∂x v = 0 ,

v + ∂x u = 0 .

Weak formulation xir

Z

xir

Z f φh −

xil

Z

xil

xir

Z

xir

v φh − xil

xil

v φ0h + vbr φh (xir ) − vbl φh (xil ) = 0 , uφ0h + ubr φh (xir ) − ubl φh (xil ) = 0 .

(1)

Shallow Water Equations Generalities dG discretization Extension to dispersive equations Motivations The physical model Reformulation of the system High order derivatives Handling breaking waves (work with G. Richard) Numerical validations Perspectives

. Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

15 / 23

LDG formalism SHARK-FV

Simplified case : T = ∂x 2

Arnaud Duran

Consider the second order ODE : f − ∂x2 u = 0 .

(1)

dG discretization

(1) reduces to a coupled system of first order equations. f + ∂x v = 0 ,

Extension to dispersive equations

v + ∂x u = 0 .

Motivations The physical model Reformulation of the system High order derivatives

Weak formulation xir

Z

xir

Z f φh −

xil

Z

xil

xir

Z

xir

v φh − xil

xil

Shallow Water Equations Generalities

v φ0h + vbr φh (xir ) − vbl φh (xil ) = 0 ,

Handling breaking waves (work with G. Richard)

uφ0h + ubr φh (xir ) − ubl φh (xil ) = 0 .

Numerical validations Perspectives

LDG schemes : [B. Cockburn, C.-W. Shu, 1998] The Local Discontinuous Galerkin method for time-dependent convection-diffusion systems . Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

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Outline SHARK-FV Arnaud Duran

1

Shallow Water Equations - Generalities

Shallow Water Equations Generalities dG discretization

2

dG discretization

3

Extension to dispersive equations

4

Handling breaking waves (work with G. Richard)

5

Perspectives

Arnaud Duran (ICJ)

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

SHARK-FV

19/05/2017

16 / 23

Switching method : press ENTER and hope ... SHARK-FV Arnaud Duran

Protocol : At each time step

Shallow Water Equations Generalities

Detection : evaluation of Ik on each cell k. [L. Krivodonova et al, 2004] Shock detection and limiting with

dG discretization

discontinuous Galerkin methods for hyperbolic conservation laws

Extension to dispersive equations

Determination of the breaking area.

Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Switching strategy Suppress of the dispersive terms on the targeted area. Application of a limiter to the hyperbolic part (Shallow Water).

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

17 / 23

Switching method : press ENTER and hope ... SHARK-FV Arnaud Duran

Protocol : At each time step Detection : evaluation of Ik on each cell k.

Shallow Water Equations Generalities

[L. Krivodonova et al, 2004] Shock detection and limiting with discontinuous Galerkin methods for hyperbolic conservation laws

dG discretization

Determination of the breaking area.

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Switching strategy Suppress of the dispersive terms on the targeted area. Application of a limiter to the hyperbolic part (Shallow Water).

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

17 / 23

Switching method : press ENTER and hope ... SHARK-FV Arnaud Duran

Protocol : At each time step Detection : evaluation of Ik on each cell k.

Shallow Water Equations Generalities

[L. Krivodonova et al, 2004] Shock detection and limiting with discontinuous Galerkin methods for hyperbolic conservation laws

dG discretization

Determination of the breaking area.

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Switching strategy Suppress of the dispersive terms on the targeted area. Application of a limiter to the hyperbolic part (Shallow Water).

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

17 / 23

Switching method : press ENTER and hope ... SHARK-FV Arnaud Duran

Protocol : At each time step Detection : evaluation of Ik on each cell k.

Shallow Water Equations Generalities

[L. Krivodonova et al, 2004] Shock detection and limiting with discontinuous Galerkin methods for hyperbolic conservation laws

dG discretization

Determination of the breaking area.

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Switching strategy Suppress of the dispersive terms on the targeted area. Application of a limiter to the hyperbolic part (Shallow Water).

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

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Through a more rigorous approach SHARK-FV Arnaud Duran

. Account for the mechanical energy dissipation through a third variable ϕ.

Shallow Water Equations Generalities dG discretization

A new model (G. Richard, 2016)

Extension to dispersive equations

˜ = B(U, ˜ z) + D(U, ˜ z) ∂t U˜ + ∂x G˜(U)

Handling breaking waves (work with G. Richard)

with :      hu h 0 1  ˜ = ˜ = −gh∂x z  U˜ =  hu  , G˜(U)  gh2 + h3 ϕ + hu 2  , B(U) 2 hϕ 0 huϕ 

Numerical validations Perspectives

. A simple additional transport equation in the hyperbolic part !

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

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Convergence analysis and model comparison SHARK-FV

Profiles

Arnaud Duran Shallow Water Equations Generalities dG discretization Extension to dispersive equations Handling breaking waves (work with G. Richard)

Convergence rates N 1 2 3 4 5

20 2.5e-1 7.5e-2 4.5e-3 7.0e-4 6.1e-5

Arnaud Duran (ICJ)

40 4.2e-2 7.5e-3 3.0e-4 1.6e-5 7.6e-7

Ne 80 1.0e-3 6.2e-4 1.7e-5 4.6e-7 1.0e-8

Numerical validations Perspectives

160 2.8e-3 6.5e-5 9.4e-7 1.4e-8 1.6e-10 SHARK-FV

320 9.6e-4 7.7e-6 5.7e-8 4.4e-10 3.1e-12

order 1.9 3.2 4.0 5.1 6.1 19/05/2017

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Convergence analysis and model comparison SHARK-FV

Profiles

Arnaud Duran Shallow Water Equations Generalities dG discretization Extension to dispersive equations Handling breaking waves (work with G. Richard)

Convergence rates N 1 2 3 4 5

20 2.5e-1 7.5e-2 4.5e-3 7.0e-4 6.1e-5

Arnaud Duran (ICJ)

40 4.2e-2 7.5e-3 3.0e-4 1.6e-5 7.6e-7

Ne 80 1.0e-3 6.2e-4 1.7e-5 4.6e-7 1.0e-8

Numerical validations Perspectives

160 2.8e-3 6.5e-5 9.4e-7 1.4e-8 1.6e-10 SHARK-FV

320 9.6e-4 7.7e-6 5.7e-8 4.4e-10 3.1e-12

order 1.9 3.2 4.0 5.1 6.1 19/05/2017

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CPU time SHARK-FV Arnaud Duran Shallow Water Equations Generalities

Evolution of the ratio τ = ρo /ρc . ρ : mean iteration time (based on 1000 iterations).

dG discretization

Ne N 1 2 3 4 5 6

1000 3.23 4.09 5.32 6.01 6.66 7.15

Arnaud Duran (ICJ)

2000 3.21 4.27 5.11 5.77 6.38 6.99

3000 3.04 4.14 5.03 5.67 6.32 7.05

4000 2.96 4.01 4.97 5.63 6.30 6.97

SHARK-FV

5000 2.94 3.90 4.91 5.51 6.26 6.86

6000 2.90 3.84 4.87 5.55 6.16 6.54

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

19/05/2017

20 / 23

Outline SHARK-FV Arnaud Duran

1

Shallow Water Equations - Generalities

Shallow Water Equations Generalities dG discretization

2

dG discretization

3

Extension to dispersive equations

4

Handling breaking waves (work with G. Richard)

5

Perspectives

Arnaud Duran (ICJ)

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

SHARK-FV

19/05/2017

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Perspectives SHARK-FV

Boundary conditions

Arnaud Duran

→ Modelling, Numerical methods. → Theoretical investigations.

Shallow Water Equations Generalities dG discretization Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

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Perspectives SHARK-FV

Boundary conditions

Arnaud Duran

→ Modelling, Numerical methods. → Theoretical investigations.

Shallow Water Equations Generalities dG discretization

Handling breaking waves → Coupling SW/GN, smoothness criteria. → Works of S. Gavrilyuk and collaboration with G. Richard (in progress.)

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

22 / 23

Perspectives SHARK-FV

Boundary conditions

Arnaud Duran

→ Modelling, Numerical methods. → Theoretical investigations.

Shallow Water Equations Generalities dG discretization

Handling breaking waves

Extension to dispersive equations

→ Coupling SW/GN, smoothness criteria. → Works of S. Gavrilyuk and collaboration with G. Richard (in progress.)

Handling breaking waves (work with G. Richard) Numerical validations

Numerical treatment of the non-hydrostatic terms

Perspectives

→ Weak formulations. → Numerical exploration (linear solvers, matrix storage, re-numbering). → Alternative approaches (quadrature rules, Finite Volume methods, FEM).

Arnaud Duran (ICJ)

SHARK-FV

19/05/2017

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SHARK-FV Arnaud Duran Shallow Water Equations Generalities dG discretization

Thanks !

Extension to dispersive equations Handling breaking waves (work with G. Richard) Numerical validations Perspectives

Arnaud Duran (ICJ)

SHARK-FV

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