New test for Tet10 mass matrix

2026-08-06 04:21:33 +00:00 · 2017-08-20 19:57:29 +03:00
parent 25d5907e9c
commit bce05b9b37
1 changed files with 47 additions and 0 deletions
@@ -0,0 +1,47 @@
+# This file is a part of JuliaFEM.
+# License is MIT: see https://github.com/JuliaFEM/JuliaFEM.jl/blob/master/LICENSE.md
+
+using JuliaFEM
+using JuliaFEM: assemble_mass_matrix!
+using JuliaFEM.Testing
+
+@testset "test tet10 mass matrix" begin
+    X = Dict(
+             1 => [2.0, 3.0, 4.0],
+             2 => [6.0, 3.0, 2.0],
+             3 => [2.0, 5.0, 1.0],
+             4 => [4.0, 3.0, 6.0])
+    X[5] = 1/2*(X[1] + X[2])
+    X[6] = 1/2*(X[2] + X[3])
+    X[7] = 1/2*(X[3] + X[1])
+    X[8] = 1/2*(X[1] + X[4])
+    X[9] = 1/2*(X[2] + X[4])
+    X[10] = 1/2*(X[3] + X[4])
+
+    element = Element(Tet10, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
+    update!(element, "youngs modulus", 480.0)
+    update!(element, "poissons ratio", 1/3)
+    update!(element, "geometry", X)
+    update!(element, "density", 105.0)
+
+    body = Problem(Heat, "TET", 1)
+    add_elements!(body, [element])
+    assemble!(body, 0.0)
+    assemble_mass_matrix!(body, 0.0)
+    #println(body.assembly.K)
+    M = full(body.assembly.M)
+
+    M_expected = [
+        6   1   1   1  -4  -6  -4  -4  -6  -6 
+        1   6   1   1  -4  -4  -6  -6  -4  -6
+        1   1   6   1  -6  -4  -4  -6  -6  -4
+        1   1   1   6  -6  -6  -6  -4  -4  -4
+       -4  -4  -6  -6  32  16  16  16  16   8
+       -6  -4  -4  -6  16  32  16   8  16  16
+       -4  -6  -4  -6  16  16  32  16   8  16
+       -4  -6  -6  -4  16   8  16  32  16  16
+       -6  -4  -6  -4  16  16   8  16  32  16
+       -6  -6  -4  -4   8  16  16  16  16  32]
+
+    @test isapprox(M, M_expected)
+end