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NickNick9 merged 1 commit into from
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turek 2d example #158

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34 changes: 34 additions & 0 deletions iga/use_cases/turek_2d_sbm/FluidMaterials.json
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{
"properties": [
{
"model_part_name": "IgaModelPart",
"properties_id": 1,
"Material": {
"constitutive_law": {
"name": "Newtonian2DLaw"
},
"Variables": {
"DENSITY": 1000.0,
"DYNAMIC_VISCOSITY": 1.0,
"PENALTY_FACTOR": 0.0
},
"Tables": null
}
},
{
"model_part_name": "IgaModelPart.SBM_Support_inner",
"properties_id": 2,
"Material": {
"constitutive_law": {
"name": "Newtonian2DLaw"
},
"Variables": {
"DENSITY": 1000.0,
"DYNAMIC_VISCOSITY": 1.0,
"PENALTY_FACTOR": 0.0
},
"Tables": null
}
}
]
}
203 changes: 203 additions & 0 deletions iga/use_cases/turek_2d_sbm/ProjectParameters_2D_fluid.json
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{
"analysis_stage": "KratosMultiphysics.FluidDynamicsApplication.fluid_dynamics_analysis",
"problem_data": {
"problem_name": "turek_sbm_single_patch",
"echo_level": 1,
"parallel_type": "OpenMP",
"start_time": 0.0,
"end_time": 10.0
},
"solver_settings": {
"solver_type": "monolithic_iga",
"time_scheme": "bdf2_higher_order_vms",
"analysis_type": "non_linear",
"model_part_name": "IgaModelPart",
"domain_size": 2,
"model_import_settings": {
"input_type": "use_input_model_part"
},
"material_import_settings": {
"materials_filename": "FluidMaterials.json"
},
// "linear_solver_settings": {
// "solver_type": "skyline_lu_factorization"
// },
"linear_solver_settings": { "solver_type": "bicgstab", "tolerance": 1.0e-14, "max_iteration": 1000, "scaling": true, "preconditioner_type": "ilu0"},
"echo_level": 1,
"enforce_element_and_conditions_replacement": false,
"compute_reactions": false,
"maximum_iterations": 50,
"relative_velocity_tolerance": 1e-11,
"absolute_velocity_tolerance": 1e-11,
"relative_pressure_tolerance": 1e-9,
"absolute_pressure_tolerance": 1e-9,
"time_stepping": {
"time_step": 0.005,
"automatic_time_step": false
},
"skip_entities_replace_and_check": true
},
"modelers": [
{
"modeler_name": "ImportNurbsSbmModeler",
"Parameters": {
"input_filename": "turek_nurbs.json",
"model_part_name": "initial_skin_model_part_in",
"link_layer_to_condition_name": [
{
"layer_name": "Layer0",
"condition_name": "SbmFluidConditionDirichlet"
}
]
}
},
{
"modeler_name": "NurbsGeometryModelerSbm",
"Parameters": {
"model_part_name": "IgaModelPart",
"lower_point_xyz": [0.0, 0.0, 0.0],
"upper_point_xyz": [2.5, 0.41, 0.0],
"lower_point_uvw": [0.0, 0.0, 0.0],
"upper_point_uvw": [2.5, 0.41, 0.0],
"polynomial_order": [1, 1],
// Roughly square background cells for a 2.5 x 0.41 box.
// "number_of_knot_spans": [25, 4], // m0
// "number_of_knot_spans": [50, 8], // m1
// "number_of_knot_spans": [100, 16], // m2
// "number_of_knot_spans": [200, 33], // m3
"number_of_knot_spans": [400, 66], // m4
// "number_of_knot_spans": [800, 131], // m5
// "number_of_knot_spans": [1600, 262], // m6
"number_initial_points_if_importing_nurbs": 1000,
"lambda_outer": 0.5,
"lambda_inner": 0.0,
"number_of_inner_loops": 1,
"skin_model_part_inner_initial_name": "initial_skin_model_part_in",
"skin_model_part_name": "skin_model_part"
}
},
{
"modeler_name": "IgaModelerSbm",
"Parameters": {
"echo_level": 0,
"skin_model_part_name": "skin_model_part",
"analysis_model_part_name": "IgaModelPart",
"integrate_on_true_boundary": true,
"element_condition_list": [
{
"geometry_type": "GeometrySurface",
"iga_model_part": "FluidDomain",
"type": "element",
"name": "NavierStokesElement",
// "name": "StokesElement",
"shape_function_derivatives_order": 3
},
{
"geometry_type": "SurfaceEdge",
"iga_model_part": "SBM_Support_outer",
"type": "condition",
"name": "SupportFluidCondition",
"shape_function_derivatives_order": 2,
"brep_ids": [2, 4]
},
{
"geometry_type": "SurfaceEdge",
"iga_model_part": "Inlet_Velocity",
"type": "condition",
"name": "SupportFluidCondition",
"shape_function_derivatives_order": 2,
"brep_ids": [5]
},
{
"geometry_type": "SurfaceEdge",
"iga_model_part": "Outlet_Pressure",
"type": "condition",
"name": "SupportPressureCondition",
"shape_function_derivatives_order": 2,
"brep_ids": [3]
},
{
"boundary_role": "internal",
"geometry_type": "SurfaceEdge",
"iga_model_part": "SBM_Support_inner",
"type": "condition",
"name": "SbmCondition",
"shape_function_derivatives_order": 7,
"sbm_parameters": {
"is_inner": true
}
}
]
}
}
],
"processes": {
"additional_processes": [
{
"python_module": "assign_iga_external_conditions_process",
"kratos_module": "KratosMultiphysics.IgaApplication",
"process_name": "AssignIgaExternalConditionsProcess",
"Parameters": {
"model_part_name": "IgaModelPart",
"echo_level": 0,
"element_condition_list": [
{
"iga_model_part": "IgaModelPart.FluidDomain",
"variables": [
{
"variable_name": "BODY_FORCE",
"value": ["0.0", "0.0"]
}
]
},
{
"iga_model_part": "IgaModelPart.SBM_Support_outer",
"variables": [
{
"variable_name": "VELOCITY",
"value": ["0.0", "0.0"]
}
]
},
{
"iga_model_part": "IgaModelPart.Inlet_Velocity",
"variables": [
{
"variable_name": "VELOCITY",
"value": [
"0.5*(1 - cos(3.141592653589793 * (t + 2.0 - sqrt((t - 2.0)*(t - 2.0))) / 4.0)) * (0.2 * 1.5 * 4 * y * (0.41 - y) / (0.41 * 0.41))",
"0.0"
]
}
]
},
{
"iga_model_part": "IgaModelPart.Outlet_Pressure",
"variables": [
{
"variable_name": "PRESSURE",
"value": "0.0"
}
]
}
]
}
}
],
"dirichlet_process_list": [
{
"kratos_module": "KratosMultiphysics",
"python_module": "assign_vector_variable_to_nodes_process",
"Parameters": {
"model_part_name": "skin_model_part.inner",
"variable_name": "VELOCITY",
"value": ["0.0", "0.0", "0.0"]
}
}
],
"constraints_process_list": []
},
"output_processes": {
"output_process_list": []
}
}
53 changes: 53 additions & 0 deletions iga/use_cases/turek_2d_sbm/README.md
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# 2D Turek SBM Example

Single-patch SBM/IGA version of the classical 2D Turek cylinder benchmark.

This example uses:
- the unordered Turek NURBS skin for the immersed cylinder
- a single Cartesian background patch generated with `NurbsGeometryModelerSbm`
- Turek-style boundary conditions: ramped parabolic inlet, no-slip walls and cylinder, zero outlet pressure

## Files

- `ProjectParameters_2D_fluid.json`: fluid setup and boundary conditions
- `FluidMaterials.json`: 2D Newtonian material
- `turek_nurbs_unordered.json`: immersed cylinder skin
- `run_and_post_nurbs.py`: run the case and create the plots and GIFs
- `plot_geometry.py`: plot the background mesh, skin boundary, and surrogate boundary

## Python Dependencies

The post-processing scripts require:
- `numpy`
- `matplotlib`
- `imageio`

If one of them is missing, the script stops immediately with a clear error message.

If a `latex` executable is available, matplotlib uses it for text rendering. Otherwise the scripts fall back to Computer Modern mathtext.

## Run

```bash
cd /home/nantonelli/Examples/iga/use_cases/turek_2d_sbm
python3 run_and_post_nurbs.py
```

To plot only the geometry:

```bash
cd /home/nantonelli/Examples/iga/use_cases/turek_2d_sbm
python3 plot_geometry.py
```

## Outputs

- `final_step_fields.png`
- `velocity.gif`
- `pressure.gif`
- `geometry_plot.png`

Internal frame caches are written into:
- `_frame_cache`
- `frames_velocity`
- `frames_pressure`
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