separated test from von mises and added MaterialModels namespace

2026-10-01 22:09:20 +00:00 · 2015-12-10 15:48:39 +02:00
parent 417dc0618d
commit e54c44cdcf
3 changed files with 164 additions and 100 deletions
@@ -0,0 +1,123 @@
+module VonMisesTests
+
+using PyPlot
+
+macro R_str(s)
+    s
+end
+
+
+using JuliaFEM.MaterialModels: hookeStiffnessTensor, calculate_stress!, State
+
+function test_von_mises_basic()
+
+    steps = 1000
+    strain_max = 0.003
+    num_cycles = 3
+    E = 200.0e3
+    nu =  0.3
+    ν = 0.3
+    C = hookeStiffnessTensor(E, ν)
+
+    ϵ_tot = zeros(Float64, (steps, 6))
+    ϵ_tot2 = zeros(Float64, (steps, 6))
+    ϵ_tot3 = zeros(Float64, (steps, 6))
+
+    # Adding only strain in x-axis and counting for the poisson effect
+    ϵ_tot[:, 1] = strain_max * sin(2 * pi * linspace(0, num_cycles, steps))
+    ϵ_tot[:, 2] = strain_max * sin(2 * pi * linspace(0, num_cycles, steps)).*-ν
+    ϵ_tot[:, 3] = strain_max * sin(2 * pi * linspace(0, num_cycles, steps)).*-ν
+    ϵ_tot[:, 4] = strain_max / 10 * sin(2 * pi * linspace(0, num_cycles, steps))
+
+    ϵ_last = zeros(Float64, (6))
+    ϵᵖ = zeros(Float64, (6))
+    σ = zeros(Float64, (6, 1))
+    σy =  200.0
+    ss = Float64[]
+    ee = Float64[]
+
+    eig_stress = zeros(Float64, (3, 3))
+    eig_vals = zeros(Float64, (steps, 3))
+
+    function fill_tensor(a, b)
+        a[1, 1] = b[1]
+        a[2, 2] = b[2]
+        a[3, 3] = b[3]
+
+        a[1, 2] = b[6]
+        a[1, 3] = b[5]
+        a[2, 3] = b[4]
+
+        a[2, 1] = b[6]
+        a[3, 1] = b[5]
+        a[3, 2] = b[4]
+    end
+
+    mat = State(C, σy, zeros(Float64, 6), zeros(Float64, 6))
+
+    info("Starting calculation")
+    tic()
+    for i=1:steps
+        ϵ_new = reshape(ϵ_tot[i, :, :], (6, 1))
+        dϵ = ϵ_new - mat.ϵ
+        calculate_stress!(dϵ, mat, Val{:vonMises})
+        mat.ϵ += vec(dϵ)
+        push!(ss, mat.σ[1])
+        push!(ee, mat.ϵ[1])
+
+        fill_tensor(eig_stress, mat.σ)
+        eig_vals[i, :] = sort(eigvals(eig_stress))
+    end
+    toc()
+    # ================ Plotting =================== #
+    n(θ, ϕ) = [sin(θ)*cos(ϕ)
+               sin(θ)*sin(ϕ)
+               cos(θ)]
+    m(θ, ϕ, χ) = [-sin(ϕ)*cos(χ)-cos(θ)*cos(ϕ)*sin(χ)
+                   cos(ϕ)*cos(χ)-cos(θ)*sin(ϕ)*sin(χ)
+                   sin(θ)*sin(χ)]
+
+    w = [sqrt(2/3) * 200 * m(54.735 * pi / 180, 45 * pi/180, x) for x=0:0.15:(2*pi+0.1)]
+    base_vec =  [1 1 1] / sqrt(3)
+
+    for i=-5:5
+        tt = [w[x] + vec(base_vec) + 50 * i for x=1:length(w)]
+        x = map(x->tt[x][1], collect(1:length(w)))
+        y = map(x->tt[x][2], collect(1:length(w)))
+        z = map(x->tt[x][3], collect(1:length(w)))
+        plot3D(x, y, z, color="blue")
+    end
+
+    tt = [w[x] + vec(base_vec) + 50 * -5 for x=1:length(w)]
+    x_start = map(x->tt[x][1], collect(1:length(w)))[1:5:end]
+    y_start = map(x->tt[x][2], collect(1:length(w)))[1:5:end]
+    z_start = map(x->tt[x][3], collect(1:length(w)))[1:5:end]
+
+
+    tt = [w[x] + vec(base_vec) + 50 * 5 for x=1:length(w)]
+    x_end = map(x->tt[x][1], collect(1:length(w)))[1:5:end]
+    y_end = map(x->tt[x][2], collect(1:length(w)))[1:5:end]
+    z_end = map(x->tt[x][3], collect(1:length(w)))[1:5:end]
+
+    for i=1:length(x_start)
+        x = [x_start[i], x_end[i]]
+        y = [y_start[i], y_end[i]]
+        z = [z_start[i], z_end[i]]
+        plot3D(x, y, z, color="blue")
+    end
+
+
+    info("Calculation finished")
+    #PyPlot.plot(ee, ss)
+    plot3D(eig_vals[:, 1], eig_vals[:, 2], eig_vals[:, 3], color="red")
+    PyPlot.title("Stress path and von Mises yield surface")
+    PyPlot.xlabel("Eig Stress 1")
+    PyPlot.ylabel("Eig Stress 2")
+    PyPlot.zlabel("Eig Stress 3")
+    PyPlot.grid()
+    PyPlot.show()
+end
+
+test_von_mises_basic()
+
+end