Default BC functions for P4est , Tree and Structured meshes

docs/src/meshes/p4est_mesh.md

@@ -939,3 +939,11 @@ rebalance_solver!(u0, mesh, equations, dg, cache, old_global_first_quadrant)
 reinitialize_boundaries!(semi.boundary_conditions, cache) # Needs to be called after `rebalance_solver!`
 ```
 This code could then be placed in the [`resize!`](https://github.com/trixi-framework/Trixi.jl/blob/eaeb04113523500ed831e3ab459694f12f7a49ea/src/time_integration/methods_2N.jl#L251-L255) function of a corresponding multirate integrator to ensure load-balancing for simulations involving AMR.
+
+### Boundary conditions
+For `P4est meshes`, boundary conditions are defined and stored in dictionaries (as shown  for example in `examples/p4est_2d_dgsem/elixir_advection_diffusion_nonperiodic_amr.jl`). If you’d like to apply the same condition to every face of the mesh, you can use the convenient functions `boundary_condition_default_p4est_2D` and `boundary_condition_default_p4est_3D`. For example, in the two dimensional case:
+
+```julia
+boundary_condition = boundary_condition_slip_wall
+boundary_conditions = boundary_condition_default_p4est_2D(boundary_condition)
+```

docs/src/meshes/structured_mesh.md

@@ -11,3 +11,11 @@ such as the compressible Euler equations can use [`FluxRotated`](@ref) to
 wrap numerical fluxes implemented only for Cartesian meshes. This simplifies
 the re-use of existing functionality for the [`TreeMesh`](@ref) but is usually
 less efficient, cf. [PR #550](https://github.com/trixi-framework/Trixi.jl/pull/550).
+
+### Boundary conditions
+For `Structured meshes`, boundary conditions are defined and stored in named tuples (as shown for example in `examples/structured_1d_dgsem/elixir_euler_source_terms_nonperiodic.jl`). If you’d like to apply the same condition to every face of the mesh, you can use the convenient functions `boundary_condition_default_structured_1D`, `boundary_condition_default_structured_2D`  and `boundary_condition_default_structured_3D`. For example, in the one dimensional case:
+
+```julia
+boundary_condition = BoundaryConditionDirichlet(initial_condition)
+boundary_conditions = boundary_condition_default_structured_1D(boundary_condition)
+```

docs/src/meshes/tree_mesh.md

@@ -9,3 +9,13 @@ It is limited to hypercube domains (that is, lines in 1D, squares in 2D and cube
 Due to its Cartesian nature, (numerical) fluxes need to implement methods
 dispatching on the `orientation::Integer` as described in the
 [conventions](@ref conventions).
+
+
+### Boundary conditions
+For `TreeMesh`es, boundary conditions are defined and stored in named tuples (as shown  for example in `examples/tree_2d_dgsem/elixir_advection_diffusion_nonperiodic.jl`). If you’d like to apply the same condition to every face of the mesh, you can use the convenient `functions boundary_condition_default_tree_1D`, `boundary_condition_default_tree_2D` and `boundary_condition_default_tree_3D`. For example, in the two dimensional case:
+
+```julia
+initial_condition = initial_condition_eriksson_johnson
+
+boundary_conditions =  boundary_condition_default_tree_2D(BoundaryConditionDirichlet(initial_condition))
+```

src/Trixi.jl

@@ -220,6 +220,14 @@ export initial_condition_constant,
        initial_condition_weak_blast_wave
 
 export boundary_condition_do_nothing,
+       boundary_condition_default_p4est_2D,
+       boundary_condition_default_p4est_3D,
+       boundary_condition_default_structured_1D,
+       boundary_condition_default_structured_2D,
+       boundary_condition_default_structured_3D,
+       boundary_condition_default_tree_1D,
+       boundary_condition_default_tree_2D,
+       boundary_condition_default_tree_3D,
        boundary_condition_periodic,
        BoundaryConditionDirichlet,
        BoundaryConditionNeumann,

src/solvers/dgsem_unstructured/sort_boundary_conditions.jl

@@ -124,4 +124,200 @@ end
 
 # @eval due to @muladd
 @eval Adapt.@adapt_structure(UnstructuredSortedBoundaryTypes)
-end # @muladd
+
+
+"""
+    boundary_condition_default_p4est_2D(boundary_condition)
+
+Create a default boundary condition dictionary for p4est meshes in 2D
+that use the standard boundary naming convention.
+
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary
+- `:x_pos`: positive x-direction boundary
+- `:y_neg`: negative y-direction boundary
+- `:y_pos`: positive y-direction boundary
+
+# Arguments
+- `boundary_condition`: The boundary condition function to apply to all boundaries
+
+# Returns
+- `Dict{Symbol, Any}`: Dictionary mapping boundary names to the boundary condition
+"""
+function boundary_condition_default_p4est_2D(boundary_condition)
+
+     return Dict(:x_neg => boundary_condition,
+                 :y_neg => boundary_condition,
+                 :y_pos => boundary_condition,
+                 :x_pos => boundary_condition)
+end 
+
+"""
+    boundary_condition_default_3D(boundary_condition)
+
+Create a default boundary condition dictionary for p4est meshes in 3D
+that use the standard boundary naming convention.
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary
+- `:x_pos`: positive x-direction boundary
+- `:y_neg`: negative y-direction boundary
+- `:y_pos`: positive y-direction boundary
+- `:z_neg`: negative z-direction boundary
+- `:z_pos`: positive z-direction boundary
+# Arguments
+- `boundary_condition`: The boundary condition function to apply to all boundaries
+# Returns
+- `Dict{Symbol, Any}`: Dictionary mapping boundary names to the boundary condition
+"""
+
+function boundary_condition_default_p4est_3D(boundary_condition)
+
+     return Dict(:x_neg => boundary_condition,
+                  :x_pos => boundary_condition,
+                  :y_neg => boundary_condition,
+                  :y_pos => boundary_condition,
+                  :z_neg => boundary_condition,
+                  :z_pos => boundary_condition)
+end
+
+
+"""
+    boundary_condition_default_structured_1D(boundary_condition)
+
+Create a default boundary condition dictionary for structured meshes in 1D
+that use the standard boundary naming convention.
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary
+- `:x_pos`: positive x-direction boundary   
+# Arguments
+- `boundarycondition`: The boundary condition function to apply to all boundaries
+# Returns
+- Named tuple mapping boundary names to the boundary condition
+"""
+function boundary_condition_default_structured_1D(boundary_condition)
+
+    return (x_neg = boundary_condition,
+            x_pos = boundary_condition)
+end
+"""
+    boundary_condition_default_structured_2D(boundary_condition)
+
+Create a default boundary condition dictionary for structured meshes in 2D
+that use the standard boundary naming convention.
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary
+- `:x_pos`: positive x-direction boundary   
+- `:y_neg`: negative y-direction boundary
+- `:y_pos`: positive y-direction boundary
+# Arguments
+- `boundarycondition`: The boundary condition function to apply to all boundaries
+# Returns
+- Named tuple mapping boundary names to the boundary condition
+"""
+function boundary_condition_default_structured_2D(boundary_condition)
+
+    return (x_neg = boundary_condition,
+            x_pos = boundary_condition,
+            y_neg = boundary_condition,
+            y_pos = boundary_condition)
+end
+
+"""
+    boundary_condition_default_structured_3D(boundary_condition)
+
+Create a default boundary condition dictionary for structured meshes in 3D
+that use the standard boundary naming convention.
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary
+- `:x_pos`: positive x-direction boundary  
+- `:y_neg`: negative y-direction boundary
+- `:y_pos`: positive y-direction boundary
+- `:z_neg`: negative z-direction boundary
+- `:z_pos`: positive z-direction boundary 
+# Arguments
+- `boundarycondition`: The boundary condition function to apply to all boundaries
+# Returns
+- Named tuple mapping boundary names to the boundary condition
+"""
+function boundary_condition_default_structured_3D(boundary_condition)
+
+    return (x_neg = boundary_condition,
+            x_pos = boundary_condition,
+            y_neg = boundary_condition,
+            y_pos = boundary_condition,
+            z_neg = boundary_condition,
+            z_pos = boundary_condition)
+
+end 
+
+
+"""
+    boundary_condition_default_tree_1D(boundary_condition)
+
+Create a default boundary condition dictionary for tree meshes in 1D
+that use the standard boundary naming convention.
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary
+- `:x_pos`: positive x-direction boundary
+# Arguments
+- `boundary_condition`: The boundary condition function to apply to all boundaries
+# Returns
+- Named tuple mapping boundary names to the boundary condition
+
+"""
+function boundary_condition_default_tree_1D(boundary_condition)
+
+    return (x_neg = boundary_condition,
+            x_pos = boundary_condition)
+end
+
+"""
+    boundary_condition_default_tree_2D(boundary_condition)
+
+Create a default boundary condition dictionary for tree meshes in 2D
+that use the standard boundary naming convention.
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary    
+- `:x_pos`: positive x-direction boundary
+- `:y_neg`: negative y-direction boundary
+- `:y_pos`: positive y-direction boundary
+# Arguments
+- `boundary_condition`: The boundary condition function to apply to all boundaries
+# Returns
+- Named tuple mapping boundary names to the boundary condition
+"""
+function boundary_condition_default_tree_2D(boundary_condition)
+
+    return (x_neg = boundary_condition,
+            x_pos = boundary_condition,
+            y_neg = boundary_condition,
+            y_pos = boundary_condition)
+end
+
+"""
+    boundary_condition_default_tree_3D(boundary_condition)
+
+Create a default boundary condition dictionary for tree meshes in 3D
+that use the standard boundary naming convention.
+This function applies the same boundary condition to all standard boundaries:
+- `:x_neg`: negative x-direction boundary
+- `:x_pos`: positive x-direction boundary
+- `:y_neg`: negative y-direction boundary
+- `:y_pos`: positive y-direction boundary
+- `:z_neg`: negative z-direction boundary
+- `:z_pos`: positive z-direction boundary
+# Arguments
+- `boundary_condition`: The boundary condition function to apply to all boundaries
+# Returns
+- Named tuple mapping boundary names to the boundary condition
+"""
+function boundary_condition_default_tree_3D(boundary_condition)
+
+    return (x_neg = boundary_condition,
+            x_pos = boundary_condition,
+            y_neg = boundary_condition,
+            y_pos = boundary_condition,
+            z_neg = boundary_condition,
+            z_pos = boundary_condition)
+end
+end#@muladd