Add Stokes flow example (#54)

* Add stokes flow example

* Add test config

examples/CMakeLists.txt

@@ -3,4 +3,5 @@
 # SPDX-License-Identifier: MIT
 
 add_subdirectory(poisson)
-add_subdirectory(linelast)
+add_subdirectory(linelast)
+add_subdirectory(stokes)

examples/stokes/CMakeLists.txt

@@ -0,0 +1,15 @@
+# Copyright 2024 Lawrence Livermore National Security, LLC. See the top-level LICENSE file for details.
+#
+# SPDX-License-Identifier: MIT
+
+file(COPY stokes.sampling.yml DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes)
+file(COPY array.8.yml DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes)
+
+file(COPY generate_configs.py DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes)
+file(COPY setup_stokes.sh DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes)
+
+file(COPY meshes/square.o3.mesh DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes/meshes)
+file(COPY meshes/square-circle.msh.mfem DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes/meshes)
+file(COPY meshes/square-triangle.msh.mfem DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes/meshes)
+file(COPY meshes/square-star.msh.mfem DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes/meshes)
+file(COPY meshes/square-square.msh.mfem DESTINATION ${CMAKE_BINARY_DIR}/examples/stokes/meshes)

examples/stokes/array.8.yml

@@ -0,0 +1,116 @@
+main:
+#mode: run_example/sample_generation/build_rom/single_run
+ mode: single_run
+ use_rom: true
+ solver: stokes
+
+mesh:
+ type: component-wise
+ component-wise:
+# you can try other config files you generated by specifying it here.
+ global_config: "configs/test.box-channel.8x8.h5"
+ components:
+ - name: "empty"
+ file: "meshes/square.o3.mesh"
+ - name: "square-circle"
+ file: "meshes/square-circle.msh.mfem"
+ - name: "square-square"
+ file: "meshes/square-square.msh.mfem"
+ - name: "square-triangle"
+ file: "meshes/square-triangle.msh.mfem"
+ - name: "square-star"
+ file: "meshes/square-star.msh.mfem"
+
+domain-decomposition:
+ type: interior_penalty
+
+discretization:
+ order: 2
+ full-discrete-galerkin: false
+
+solver:
+ direct_solve: true
+ use_amg: true
+ max_iter: 1000000
+ print_level: 0
+ absolute_tolerance: 1.0e-10
+ relative_tolerance: 1.0e-10
+
+visualization:
+ enabled: true
+ visualize_error: true
+ unified_paraview: false
+ file_path:
+ prefix: paraview/8x8/stokes_array_output
+
+parameterized_problem:
+ name: flow_past_array
+ #name: stokes_channel
+
+single_run:
+ choose_from_random_sample: false
+ flow_past_array:
+ nu: 1.1
+ u0_x: 1.5
+ u0_y: -0.8
+ du_x: 0.
+ du_y: 0.
+ stokes_channel:
+ nu: 1.1
+ U: 1.5
+ L: 4.
+ x0: 2.
+
+sample_generation:
+ type: "random"
+ random_sample_generator:
+ number_of_samples: 100
+ maximum_number_of_snapshots: 100
+ parameters:
+ - key: mesh/component-wise/global_config
+ type: filename
+ minimum: 0
+ maximum: 99
+ format: "boxchannel_sample/8x8_samples/box-channel.8x8.%06d.h5"
+ - key: single_run/flow_past_array/u0_x
+ type: double
+ minimum: -1.5
+ maximum: 1.5
+ - key: single_run/flow_past_array/u0_y
+ type: double
+ minimum: -1.5
+ maximum: 1.5
+
+basis:
+ prefix: "basis/stokes_basis"
+ number_of_basis: 36
+ tags:
+ - name: "empty"
+ - name: "square-circle"
+ - name: "square-square"
+ - name: "square-triangle"
+ - name: "square-star"
+ svd:
+ save_spectrum: true
+ update_right_sv: false
+ visualization:
+ enabled: false
+ prefix: stokes_comp
+
+model_reduction:
+ rom_handler_type: mfem
+ linear_solver_type: direct
+ linear_system_type: spd
+# This is the input for saving ROM matrix/rhs system.
+ save_linear_system:
+ enabled: true
+ prefix: rom-system/stokes.8x8
+ preconditioner: gs
+ # individual/universal
+ subdomain_training: universal
+ save_operator:
+ level: component
+ prefix: "stokes_comp"
+ compare_solution:
+ enabled: true
+

examples/stokes/generate_configs.py

@@ -0,0 +1,24 @@
+import sys
+# Add path to root utils/python/ directory to find config scripts
+sys.path.insert(0, "../../../utils/python/")
+
+from config import Empty, ObjectInSpace
+from box_channel_config import BoxChannelConfig
+
+if __name__ == "__main__":
+ comp_list = {'empty': Empty(),
+ 'circle': ObjectInSpace('square-circle'),
+ 'square': ObjectInSpace('square-square'),
+ 'triangle': ObjectInSpace('square-triangle'),
+ 'star': ObjectInSpace('square-star'),}
+
+ example = BoxChannelConfig(2,2)
+ for name, comp in comp_list.items():
+ example.addComponent(comp)
+
+ example.GenerateAllConfigs(0)
+
+ test = BoxChannelConfig(8,8)
+ for name, comp in comp_list.items():
+ test.addComponent(comp)
+ test.CreateRandomConfig('test.box-channel.8x8.h5')