def updStiffMatMS(self, elmLst, elmCompStiffMat): self.K = mfem.ParBilinearForm(self.fespace) lambVec = mfem.Vector(self.fespace.GetMesh().attributes.Max()) lambVec.Assign(self.lmbda) lambVec[0] = lambVec[1] lambda_func = mfem.PWConstCoefficient(lambVec) muVec = mfem.Vector(self.fespace.GetMesh().attributes.Max()) muVec.Assign(self.mu) muVec[0] = muVec[1] mu_func = mfem.PWConstCoefficient(muVec) self.K.AddDomainIntegrator( mfem.ElasticityIntegrator(lambda_func, mu_func)) self.K.Assemble(0, elmLst, elmCompStiffMat, False, True) self.Kmat = mfem.HypreParMatrix() empty_tdof_list = intArray() self.K.FormLinearSystem(empty_tdof_list, self.x_gfBdr, self.bx, self.Kmat, self.vx.GetBlock(1), self.Bx, 1)
# A and M. lamb = mfem.Vector(pmesh.attributes.Max()) lamb.Assign(1.0) lamb[0] = lamb[1] * 50 lambda_func = mfem.PWConstCoefficient(lamb) mu = mfem.Vector(pmesh.attributes.Max()) mu.Assign(1.0) mu[0] = mu[1] * 50 mu_func = mfem.PWConstCoefficient(mu) ess_bdr = mfem.intArray(pmesh.bdr_attributes.Max()) ess_bdr.Assign(0) ess_bdr[0] = 1 a = mfem.ParBilinearForm(fespace) a.AddDomainIntegrator(mfem.ElasticityIntegrator(lambda_func, mu_func)) if (myid == 0): print("matrix ... ") a.Assemble() a.EliminateEssentialBCDiag(ess_bdr, 1.0) a.Finalize() m = mfem.ParBilinearForm(fespace) m.AddDomainIntegrator(mfem.VectorMassIntegrator()) m.Assemble() # shift the eigenvalue corresponding to eliminated dofs to a large value m.EliminateEssentialBCDiag(ess_bdr, 3.0e-300) m.Finalize() if (myid == 0): print("done. ")
def __init__(self, fespace, lmbda=1., mu=1., rho=1., visc=0.0, vess_tdof_list=None, vess_bdr=None, xess_tdof_list=None, xess_bdr=None, v_gfBdr=None, x_gfBdr=None, deform=None, velo=None, vx=None): mfem.PyTimeDependentOperator.__init__(self, 2 * fespace.GetTrueVSize(), 0.0) self.lmbda = lmbda self.mu = mu self.viscosity = visc self.deform = deform self.velo = velo self.x_gfBdr = x_gfBdr self.v_gfBdr = v_gfBdr self.vx = vx self.z = mfem.Vector(self.Height() / 2) self.z.Assign(0.0) self.w = mfem.Vector(self.Height() / 2) self.w.Assign(0.0) self.tmpVec = mfem.Vector(self.Height() / 2) self.tmpVec.Assign(0.0) self.fespace = fespace self.xess_bdr = xess_bdr self.vess_bdr = vess_bdr self.xess_tdof_list = xess_tdof_list self.vess_tdof_list = vess_tdof_list # setting up linear form cv = mfem.Vector(3) cv.Assign(0.0) #self.zero_coef = mfem.ConstantCoefficient(0.0) self.zero_coef = mfem.VectorConstantCoefficient(cv) self.bx = mfem.LinearForm(self.fespace) self.bx.AddDomainIntegrator( mfem.VectorBoundaryLFIntegrator(self.zero_coef)) self.bx.Assemble() self.bv = mfem.LinearForm(self.fespace) self.bv.AddDomainIntegrator( mfem.VectorBoundaryLFIntegrator(self.zero_coef)) self.bv.Assemble() self.Bx = mfem.Vector() self.Bv = mfem.Vector() # setting up bilinear forms self.M = mfem.ParBilinearForm(self.fespace) self.K = mfem.ParBilinearForm(self.fespace) self.S = mfem.ParBilinearForm(self.fespace) self.ro = mfem.ConstantCoefficient(rho) self.M.AddDomainIntegrator(mfem.VectorMassIntegrator(self.ro)) self.M.Assemble(0) self.M.EliminateEssentialBC(self.vess_bdr) self.M.Finalize(0) self.Mmat = self.M.ParallelAssemble() self.M_solver = mfem.CGSolver(self.fespace.GetComm()) self.M_solver.iterative_mode = False self.M_solver.SetRelTol(1e-8) self.M_solver.SetAbsTol(0.0) self.M_solver.SetMaxIter(30) self.M_solver.SetPrintLevel(0) self.M_prec = mfem.HypreSmoother() self.M_prec.SetType(mfem.HypreSmoother.Jacobi) self.M_solver.SetPreconditioner(self.M_prec) self.M_solver.SetOperator(self.Mmat) lambVec = mfem.Vector(self.fespace.GetMesh().attributes.Max()) print('Number of volume attributes : ' + str(self.fespace.GetMesh().attributes.Max())) lambVec.Assign(lmbda) lambVec[0] = lambVec[1] * 1.0 lambda_func = mfem.PWConstCoefficient(lambVec) muVec = mfem.Vector(self.fespace.GetMesh().attributes.Max()) muVec.Assign(mu) muVec[0] = muVec[1] * 1.0 mu_func = mfem.PWConstCoefficient(muVec) self.K.AddDomainIntegrator( mfem.ElasticityIntegrator(lambda_func, mu_func)) self.K.Assemble(0) # to set essential BC to zero value uncomment #self.K.EliminateEssentialBC(self.xess_bdr) #self.K.Finalize(0) #self.Kmat = self.K.ParallelAssemble() # to set essential BC to non-zero uncomment self.Kmat = mfem.HypreParMatrix() visc_coeff = mfem.ConstantCoefficient(visc) self.S.AddDomainIntegrator(mfem.VectorDiffusionIntegrator(visc_coeff)) self.S.Assemble(0) #self.S.EliminateEssentialBC(self.vess_bdr) #self.S.Finalize(0) #self.Smat = self.S.ParallelAssemble() self.Smat = mfem.HypreParMatrix() # VX solver for implicit time-stepping self.VX_solver = mfem.CGSolver(self.fespace.GetComm()) self.VX_solver.iterative_mode = False self.VX_solver.SetRelTol(1e-8) self.VX_solver.SetAbsTol(0.0) self.VX_solver.SetMaxIter(30) self.VX_solver.SetPrintLevel(0) self.VX_prec = mfem.HypreSmoother() self.VX_prec.SetType(mfem.HypreSmoother.Jacobi) self.VX_solver.SetPreconditioner(self.VX_prec) # setting up operators empty_tdof_list = intArray() self.S.FormLinearSystem(empty_tdof_list, self.v_gfBdr, self.bv, self.Smat, self.vx.GetBlock(0), self.Bv, 1) self.K.FormLinearSystem(empty_tdof_list, self.x_gfBdr, self.bx, self.Kmat, self.vx.GetBlock(1), self.Bx, 1)