(0.95.5) Bugfix in immersed phi-node (#4010)

* correct immersed nodes

* added a test

Author: simone-silvestri

Project.toml

@@ -1,7 +1,7 @@
 name = "Oceananigans"
 uuid = "9e8cae18-63c1-5223-a75c-80ca9d6e9a09"
 authors = ["Climate Modeling Alliance and contributors"]
-version = "0.95.4"
+version = "0.95.5"
 
 [deps]
 Adapt = "79e6a3ab-5dfb-504d-930d-738a2a938a0e"

src/ImmersedBoundaries/immersed_boundary_nodes.jl

@@ -9,7 +9,7 @@ const f = Face()
 @inline znode(k, ibg::IBG, ℓz) = znode(k, ibg.underlying_grid, ℓz)
 
 @inline λnode(i, ibg::IBG, ℓx) = λnode(i, ibg.underlying_grid, ℓx)
-@inline φnode(j, ibg::IBG, ℓy) = φnode(i, ibg.underlying_grid, ℓy)
+@inline φnode(j, ibg::IBG, ℓy) = φnode(j, ibg.underlying_grid, ℓy)
 
 @inline xnode(i, j, ibg::IBG, ℓx, ℓy) = xnode(i, j, ibg.underlying_grid, ℓx, ℓy)
 

test/test_grids.jl

@@ -649,6 +649,7 @@ function test_lat_lon_xyzλφ_node_nodes(FT, arch)
     zᵣ  = (-10,    0)
 
     grid = LatitudeLongitudeGrid(CPU(), FT, size=grid_size, halo=halo, latitude=lat, longitude=lon, z=zᵣ)
+    ibg  = ImmersedBoundaryGrid(grid, GridFittedBottom((x, y) -> y < 20 && y > -20 ? -50 : -0))
 
     @info "        Testing grid utils on LatitudeLongitude grid...."
 
@@ -658,15 +659,19 @@ function test_lat_lon_xyzλφ_node_nodes(FT, arch)
     @test ynode(2, 1, 2, grid, Face(), Face(), Face()) / grid.radius ≈ -FT(π/3)
     @test znode(2, 1, 2, grid, Face(), Face(), Face()) ≈ -5
 
+    @test λnode(3, 1, 2, ibg, Face(), Face(), Face()) ≈ -120
+    @test φnode(3, 2, 2, ibg, Face(), Face(), Face()) ≈ -30
+    @test xnode(5, 1, 2, ibg, Face(), Face(), Face()) / ibg.radius ≈ -FT(π/6)
+    @test ynode(2, 1, 2, ibg, Face(), Face(), Face()) / ibg.radius ≈ -FT(π/3)
+    @test znode(2, 1, 2, ibg, Face(), Face(), Face()) ≈ -5
+
     @test minimum_xspacing(grid, Face(), Face(), Face()) / grid.radius ≈ FT(π/6) * cosd(60)
     @test minimum_xspacing(grid) / grid.radius ≈ FT(π/6) * cosd(45)
     @test minimum_yspacing(grid) / grid.radius ≈ FT(π/6)
     @test minimum_zspacing(grid) ≈ 5
 
-    grid = ImmersedBoundaryGrid(grid, GridFittedBottom((x, y) -> y < 20 && y > -20 ? -50 : -0))
-
-    @test minimum_xspacing(grid, Face(), Face(), Face()) / grid.radius ≈ FT(π/6) * cosd(30)
-    @test minimum_xspacing(grid) / grid.radius ≈ FT(π/6) * cosd(15)
+    @test minimum_xspacing(ibg, Face(), Face(), Face()) / ibg.radius ≈ FT(π/6) * cosd(30)
+    @test minimum_xspacing(ibg) / ibg.radius ≈ FT(π/6) * cosd(15)
 
     return nothing
 end