# sandbox/ghigo/README

# My Sandbox

This ‘README’ provides on overview of the content of my sandbox.

## Blood Flow Modeling

#### Code

#### 1D blood flow examples

- Inviscid wave propagation in an artery
- Inviscid tourniquet
- Inviscid analytic solution by O. Delestre
- Viscous wave propagation
- Thacker solution - Oscillations in an aneurysm
- Steady solution in a stenosis
- Inviscid wave propagation in a tapered artery

## Particle-Ladden Flows

#### Code

- myembed.h: modified embed.h
- extension to 3D of interpolation and force computation on embedded boundaries;
- 2D/3D torque computation on embedded boundaries;
- Neumann boundary condition on embedded boundary (reverse engineering of the Dirichlet boundary condition);
- in
*update_tracer*, u \cdot \nabla u now takes into account non-zero face-velocity*uf*boundary conditions on embedded boundaries; - robust small cell treatment (see Colella et al., 2006, Schneiders et al., 2013).

- mypoisson.h: modified poisson.h
- in
*project*, the r.h.s. \nabla \cdot u_f now takes into account non-zero face-velocity*uf*boundary conditions on embedded boundaries.

- in
- mycentered: modified centered.h
- treatment of emmerged (solid to fluid, necessary to avoid spurious variations in drag and lift forces) and submerged (fluid to solid, necessary to avoid adaptation in solid embedded boundaries) cells;
- dedicated
*events*for moving embedded boundaries and tracers on embedded boundaries.

#### Test cases for static embedded boundaries

- Stokes flow past a static sphere: test hydrodynamic force computation
- x-direction: sphereFx.c
- y-direction: sphereFy.c
- z-direction: sphereFz.c

- Rotational stokes flow around a static sphere: test hydrodynamic torque computation
- x-direction: sphereTx.c
- y-direction: sphereTy.c
- z-direction: sphereTz.c

- Moving sphere near a wall in a Stokes flow: test projection algorithm with non-zero Dirichlet boundary conditions

#### Test cases for moving embedded boundaries with imposed motion

- Cylinder moving at the same speed as the fluid: Stokes flow
- with single projection: moving_steady1x.c
- with double projection: moving_steady1y.c

- Cylinder moving at the same speed as the fluid: Re=1000
- with single projection: moving_steady2x.c
- with double projection: moving_steady2y.c

- Stokes flow past a moving sphere: test hydrodynamic force computation
- x-direction and single projection: moving_sphereFx.c
- y-direction and double projection: moving_sphereFy.c
- z-direction and double projection: moving_sphereFz.c

- Oscillating cylinder in a quiescent fluid at Re=100 and KC=5: comparison with results from Dutsch et al., 1998
- with single projection: oscillating1x.c
- with double projection: oscillating1y.c

- Oscillating cylinder in a quiescent fluid at Re=200 and KC=10: comparison with results from Dutsch et al., 1998
- with single projection: oscillating2x.c
- with double projection: oscillating2y.c

- Oscillating sphere in a quiescent fluid at Re=40 and St=3.2: comparison with results from Schneiders et al., 2013
- with double projection: oscillating4x.c

- Vertically oscillating cylinder in a stream flow at Re=185: comparison with results from Guilmineau et al.,2002
- f=0.8f_0 with single projection: oscillating3x.c
- f=1.2f_0 with double projection: oscillating3y.c

- Starting flow around a moving cylinder: comparison with starting flow around an static cylinder
- Re = 1000: moving_starting1x.c
- Re = 9500 (underresolved): moving_starting2x.c

- Starting vortex of a NACA2414 airfoil:
- Flow past a cylinder: computation of the Strouhal number St for different 200 \leq Re \leq 500
- static cylinder with double projection: strouhal.c
- moving cylinder with double projection: moving_strouhal.c

- Flow past a square cylinder: computation of the Strouhal number St for different 250 \leq Re \leq 1000 and comparison with Okajima & al., 1982
- static cylinder with double projection: square1.c
- moving cylinder with double projection: moving_square1.c

- Flow past a rectangular cylinder (B/H=2): computation of the Strouhal number St for different 250 \leq Re \leq 1000 and comparison with Okajima & al., 1982
- static cylinder with double projection: square2.c
- moving cylinder with double projection: moving_square2.c

- Pitching NACA0015 airfoil: comparison with Schneiders et al., 2013 (results for Ma=0.3)
- 2D, with double projection: pitching-naca0015.c

#### Test cases for moving embedded boundaries with fluid-solid coupling

- Cylinder settling in a square box for Ga = 1: comparison with drag correction of Faxén,1946
- with single projection: settling_cylinder1x.c
- with double projection: settling_cylinder1y.c

#### Test cases for moving embedded boundaries with passive scalar

- Translating cylinder at Re=40 and Pe=100:
- single projection and passive scalar on the bottom half ot the domain and Dirichlet boundary conditions f=0: moving_scalar1x.c
- double projection and passive scalar with Dirichlet boundary conditions f=1: moving_scalar1y.c

- Translating cylinder at Re=400: test Strouhal number St of the Bénard–von Kármán Vortex Street
- single projection and passive scalar with Pe=100 and Neumann boundary conditions \nabla f \cdot n = 1: moving_scalar2x.c
- double projection and passive scalar with Pe = 1 and Neumann boundary conditions \nabla f \cdot n = 1: moving_scalar2y.c

## Potential bugs?

## References

[schneiders2013] |
L. Schneiders, D. Hartmann, M. Meinke, and W. Schroder. An accurate moving boundary formulation in cut-cell methods. |

[colella2006] |
Phillip Colella, Daniel Graves, Benjamin Keen, and Modiano David. A cartesian grid embedded boundary method for hyperbolic conservation laws. |

[guilmineau2002] |
E. Guilmineau and P. Queutey. A numerical simulation of vortex shedding from an oscillating circular cylinder. |

[dutsch1998] |
H. Dutsch, F. Durst, S. Becker, and H. Lienhart. Low-reynolds-number flow around an oscillating circular cylinder at low keulegan-carpenter numbers. |

[okajima1982] |
A. Okajima. Strouhal numbers of rectangular cylinders. |

[faxen1946] |
O.H. Faxen. Forces exerted on a rigid cylinder in a viscous fluid between two parallel fixed planes. |