Merge pull request #4 from veiguf/main

eig

EasyBeam/EasyBeam.py

@@ -185,10 +185,10 @@ def EigenvalueAnalysis(self, nEig=2, massMatrixType="consistent"):
         self.k = self.Assemble(self.StiffMatElem)
         self.m = self.Assemble(self.MassMatElem)
         try:
-            lambdaComplex, self.Phi = npla.eigh(self.k[self.DoF, :][:, self.DoF],
+            lambdaComplex, self.Phi = spla.eigh(self.k[self.DoF, :][:, self.DoF],
                                                 self.m[self.DoF, :][:, self.DoF],
                                                 eigvals=(0, nEig-1))
-            self.EigenvalSolver = "numpy.linalg.eigh"
+            self.EigenvalSolver = "scipy.linalg.eigh"
         except:
             lambdaComplex, self.Phi = spla.eig(self.k[self.DoF, :][:, self.DoF],
                                                  self.m[self.DoF, :][:, self.DoF])

examples/Cantilever.py

@@ -10,23 +10,30 @@
 rho = 7.85e-9
 I = b*h**3/12
 A = b*h
+nEl = 5
 
 # Initialisiern des Problems
 Cantilever = Beam2D()
 
 # Setze Elementenbeschreibung
+Cantilever.stiffMatType = "Timoshenko-Ehrenfest"
 Cantilever.stiffMatType = "Euler-Bernoulli"
+Cantilever.massMatType = "lumped"
+Cantilever.massMatType = "consistent"
 
 # Knoten [mm]
-Cantilever.N = [[0, 0],
-                [l, 0]]
+Cantilever.N = [[]]*(nEl+1)
+for i in range(nEl+1):
+    Cantilever.N[i] = [l*i/nEl, 0.0]
 
 # Elemente: verbindet die Knoten
-Cantilever.El = [[0, 1]]
+Cantilever.El = [[]]*(nEl)
+for i in range(nEl):
+    Cantilever.El[i] = [i, i+1]
 
 # Randbedingungen und Belastung [N] bzw. [Nmm]
 Cantilever.BC = [0, 1, 2]
-Cantilever.Load = [[4, F]]
+Cantilever.Load = [[3*nEl+1, F]]
 
 # Initialisieren des Modells
 Cantilever.Initialize()
@@ -43,18 +50,19 @@
 Cantilever.StaticAnalysis()
 Cantilever.Scale = 10
 Cantilever.ComputeStress()
-Cantilever.EigenvalueAnalysis(nEig=len(Cantilever.DoF))
+Cantilever.EigenvalueAnalysis(nEig=4)
 
 # Grafische Darstellung
 Cantilever.PlotMesh()
 Cantilever.PlotStress()
 Cantilever.PlotDisplacement()
-Cantilever.ScalePhi = 100
+Cantilever.ScalePhi = 10
 Cantilever.PlotMode()
 
 # With Timoshenko beams
 Cantilever.stiffMatType = "Timoshenko-Ehrenfest"
 Cantilever.EigenvalueAnalysis(nEig=len(Cantilever.DoF))
+Cantilever.ScalePhi = 100
 Cantilever.PlotMode()
 
 # Analytical values, continuous beam theory for eigenfrequencies
@@ -68,9 +76,12 @@
 print(wMax)
 
 print("first three bending modes [Hz]:")
-fB1 = 1.875**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
-fB2 = 4.694**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
-fB3 = 7.855**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
+# fB1 = 1.875**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
+# fB2 = 4.684**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
+# fB3 = 7.069**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
+fB1 = 1.87510107**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
+fB2 = 4.69409113**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
+fB3 = 7.85475744**2/(2*np.pi*l**2)*((E*I)/(rho*A))**0.5
 print(fB1)
 print(fB2)
 print(fB3)