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Author: LasNikas

src/general/neighborhood_search.jl

@@ -22,6 +22,10 @@ function deactivate_out_of_bounds_particles!(system, buffer, nhs, cell_list, v,
     return system
 end
 
+# `GridNeighborhoodSearch` with a `FullGridCellList` requires a bounding box.
+# This function deactivates particles that move outside this bounding box to prevent
+# simulation crashes.
+# Note that simply deactivating particles is only possible in combination with a 'SystemBuffer'.
 function deactivate_out_of_bounds_particles!(system, ::SystemBuffer, nhs,
                                              cell_list::FullGridCellList, v, u, semi)
     @trixi_timeit timer() "deactivate out of bounds particle" begin

src/schemes/boundary/open_boundary/system.jl

@@ -311,6 +311,11 @@ end
 
 function update_positions!(system::OpenBoundarySystem, v, u, v_ode, u_ode, semi, t)
     nhs = get_neighborhood_search(system, semi)
+
+    # `GridNeighborhoodSearch` with a `FullGridCellList` requires a bounding box.
+    # This function deactivates particles that move outside this bounding box to prevent
+    # simulation crashes.
+    # Note that simply deactivating particles is only possible in combination with a 'SystemBuffer'.
     deactivate_out_of_bounds_particles!(system, buffer(system), nhs, v, u, semi)
 end
 

src/schemes/fluid/fluid.jl

@@ -117,6 +117,11 @@ end
 
 function update_positions!(system::AbstractFluidSystem, v, u, v_ode, u_ode, semi, t)
     nhs = get_neighborhood_search(system, semi)
+
+    # `GridNeighborhoodSearch` with a `FullGridCellList` requires a bounding box.
+    # This function deactivates particles that move outside this bounding box to prevent
+    # simulation crashes.
+    # Note that simply deactivating particles is only possible in combination with a 'SystemBuffer'.
     deactivate_out_of_bounds_particles!(system, buffer(system), nhs, v, u, semi)
 end