/// <summary> /// Spatial Operators and Matrices /// </summary> /// with /// <param name="bcMap">Boundary Conditions</param> public SpatialOperator CreateAdvectionSpatialOperator(IncompressibleBoundaryCondMap bcMap) { Func <int[], int[], int[], int> QuadOrderFunction = QuadOrderFunc.SumOfMaxDegrees(); string[] parameterList; parameterList = ArrayTools.Cat(VariableNames.Velocity0Vector(D), VariableNames.Velocity0MeanVector(D)); if (!divUzero) { parameterList = ArrayTools.Cat(parameterList, "div(U)"); } SpatialOperator SO = new SpatialOperator(new string[] { "LevelSet" }, parameterList, new string[] { "Phi-Evo" }, QuadOrderFunc.NonLinear(2)); //div(u.phi) //SO.EquationComponents["Phi-Evo"].Add(new LevelSetUpwindFlux(GridDat, bcMap)); SO.EquationComponents["Phi-Evo"].Add(new LevelSetLLFFlux(GridDat, bcMap)); //bcMap.PhysMode = PhysicsMode.Multiphase; //SO.EquationComponents["Phi-Evo"].Add(new LinearizedScalarConvection(D, bcMap,null)); //SO.EquationComponents["Phi-Evo"].Add(new LevelSetAdvectionCentralFlux(D)); //-phi*div(u) if (!divUzero) { SO.EquationComponents["Phi-Evo"].Add(new FextSource()); } //penalization //Lsevo.EquationComponents["Phi-Evo"].Add(new JumpPenalization.GradientJumpForm2()); SO.Commit(); return(SO); }
SpatialOperator CreateAdvectionSpatialOperator(IncompressibleBoundaryCondMap bcMap) { Func <int[], int[], int[], int> QuadOrderFunction = QuadOrderFunc.SumOfMaxDegrees(); string[] parameterList; parameterList = ArrayTools.Cat( VariableNames.Velocity0Vector(D), VariableNames.Velocity0MeanVector(D), "div(U)"); SpatialOperator SO = new SpatialOperator(new string[] { "LevelSet" }, parameterList, new string[] { "Phi-Evo" }, QuadOrderFunc.NonLinear(2)); //div(u*phi) SO.EquationComponents["Phi-Evo"].Add(new LevelSetLLFFlux(GridDat, bcMap)); //-phi*div(u) SO.EquationComponents["Phi-Evo"].Add(new FextSource()); SO.Commit(); return(SO); }
/// <summary> /// Obtaining the time integrated spatial discretization of the reinitialization equation in a narrow band around the zero level set, based on a Godunov's numerical Hamiltonian calculation /// </summary> /// <param name="LS"> The level set function </param> /// <param name="Restriction"> The narrow band around the zero level set </param> /// <param name="NumberOfTimesteps"> /// maximum number of pseudo-timesteps /// </param> /// <param name="thickness"> /// The smoothing width of the signum function. /// This is the main stabilization parameter for re-initialization. /// It should be set to approximately 3 cells. /// </param> /// <param name="TimestepSize"> /// size of the pseudo-timestep /// </param> public void ReInitialize(LevelSet LS, SubGrid Restriction, double thickness, double TimestepSize, int NumberOfTimesteps) { using (var tr = new FuncTrace()) { // log parameters: tr.Info("thickness: " + thickness.ToString(NumberFormatInfo.InvariantInfo)); tr.Info("TimestepSize: " + TimestepSize.ToString(NumberFormatInfo.InvariantInfo)); tr.Info("NumberOfTimesteps: " + NumberOfTimesteps); ExplicitEuler TimeIntegrator; SpatialOperator SO; Func <int[], int[], int[], int> QuadratureOrder = QuadOrderFunc.NonLinear(3); if (m_ctx.SpatialDimension == 2) { SO = new SpatialOperator(1, 5, 1, QuadratureOrder, new string[] { "LS", "LSCGV", "LSDG[0]", "LSUG[0]", "LSDG[1]", "LSUG[1]", "Result" }); SO.EquationComponents["Result"].Add(new GodunovHamiltonian(m_ctx, thickness)); SO.Commit(); TimeIntegrator = new RungeKutta(m_Scheme, SO, new CoordinateMapping(LS), new CoordinateMapping(LSCGV, LSDG[0], LSUG[0], LSDG[1], LSUG[1]), sgrd: Restriction); } else { SO = new SpatialOperator(1, 7, 1, QuadratureOrder, new string[] { "LS", "LSCGV", "LSDG[0]", "LSUG[0]", "LSDG[1]", "LSUG[1]", "LSDG[2]", "LSUG[2]", "Result" }); SO.EquationComponents["Result"].Add(new GodunovHamiltonian(m_ctx, thickness)); SO.Commit(); TimeIntegrator = new RungeKutta(m_Scheme, SO, new CoordinateMapping(LS), new CoordinateMapping(LSCGV, LSDG[0], LSUG[0], LSDG[1], LSUG[1], LSDG[2], LSUG[2]), sgrd: Restriction); } // Calculating the gradients in each sub-stage of a Runge-Kutta integration procedure ExplicitEuler.ChangeRateCallback EvalGradients = delegate(double t1, double t2) { LSUG.Clear(); CalculateLevelSetGradient(LS, LSUG, "Upwind", Restriction); LSDG.Clear(); CalculateLevelSetGradient(LS, LSDG, "Downwind", Restriction); LSCG.Clear(); CalculateLevelSetGradient(LS, LSCG, "Central", Restriction); LSCGV.Clear(); var VolMask = (Restriction != null) ? Restriction.VolumeMask : null; LSCGV.ProjectAbs(1.0, VolMask, LSCG.ToArray()); }; TimeIntegrator.OnBeforeComputeChangeRate += EvalGradients; { EvalGradients(0, 0); var GodunovResi = new SinglePhaseField(LS.Basis, "Residual"); SO.Evaluate(1.0, 0.0, LS.Mapping, TimeIntegrator.ParameterMapping.Fields, GodunovResi.Mapping, Restriction); //Tecplot.Tecplot.PlotFields(ArrayTools.Cat<DGField>( LSUG, LSDG, LS, GodunovResi), "Residual", 0, 3); } // pseudo-timestepping // =================== double factor = 1.0; double time = 0; LevelSet prevLevSet = new LevelSet(LS.Basis, "prevLevSet"); CellMask RestrictionMask = (Restriction == null) ? null : Restriction.VolumeMask; for (int i = 0; (i < NumberOfTimesteps); i++) { tr.Info("Level set reinitialization pseudo-timestepping, timestep " + i); // backup old Levelset // ------------------- prevLevSet.Clear(); prevLevSet.Acc(1.0, LS, RestrictionMask); // time integration // ---------------- double dt = TimestepSize * factor; tr.Info("dt = " + dt.ToString(NumberFormatInfo.InvariantInfo) + " (factor = " + factor.ToString(NumberFormatInfo.InvariantInfo) + ")"); TimeIntegrator.Perform(dt); time += dt; // change norm // ------ prevLevSet.Acc(-1.0, LS, RestrictionMask); double ChangeNorm = prevLevSet.L2Norm(RestrictionMask); Console.WriteLine("Reinit: PseudoTime: {0} - Changenorm: {1}", i, ChangeNorm); //Tecplot.Tecplot.PlotFields(new SinglePhaseField[] { LS }, m_ctx, "Reinit-" + i, "Reinit-" + i, i, 3); } //*/ } }
/// <summary> /// /// </summary> /// <param name="jCell"></param> /// <param name="AcceptedMask"></param> /// <param name="Phi"></param> /// <param name="gradPhi"></param> /// <param name="__DiffusionCoeff">Output: if artificial diffusion is turned</param> /// <param name="MaxAllowedPhi">Input: upper threshold for the values of <paramref name="Phi"/> in cell <see cref="jCell"/>.</param> /// <param name="MinAllowedPhi">Input: lower threshold for the values of <paramref name="Phi"/> in cell <see cref="jCell"/>.</param> /// <returns></returns> public bool LocalSolve_Iterative(int jCell, BitArray AcceptedMask, SinglePhaseField Phi, VectorField <SinglePhaseField> gradPhi, SinglePhaseField __DiffusionCoeff, double MaxAllowedPhi, double MinAllowedPhi) { //this.LocalSolve_Geometric(jCell, AcceptedMask, Phi, +1, out MinAllowedPhi, out MaxAllowedPhi);) { int N = this.LevelSetBasis.GetLength(jCell); int i0G = this.LevelSetMapping.GlobalUniqueCoordinateIndex(0, jCell, 0); int i0L = this.LevelSetMapping.LocalUniqueCoordinateIndex(0, jCell, 0); SinglePhaseField __AcceptedMask = new SinglePhaseField(new Basis(this.GridDat, 0), "accepted"); for (int j = 0; j < AcceptedMask.Length; j++) { __AcceptedMask.SetMeanValue(j, AcceptedMask[j] ? 1.0 : 0.0); } // subgrid on which we are working, consisting only of one cell SubGrid jCellGrid = new SubGrid(new CellMask(this.GridDat, Chunk.GetSingleElementChunk(jCell))); // create spatial operator IEvaluatorNonLin evo; { SpatialOperator op = new SpatialOperator(1, 2, 1, QuadOrderFunc.NonLinear(2), "Phi", "dPhi_dx0", "dPhi_dx1", "cod1"); op.EquationComponents["cod1"].Add(new ReinitOperator()); op.EdgeQuadraturSchemeProvider = g => (new EdgeQuadratureScheme(domain: EdgeMask.GetEmptyMask(g))); op.VolumeQuadraturSchemeProvider = g => (new CellQuadratureScheme(domain: jCellGrid.VolumeMask)); op.Commit(); evo = op.GetEvaluatorEx(Phi.Mapping.Fields, gradPhi.Mapping.Fields, Phi.Mapping); evo.ActivateSubgridBoundary(jCellGrid.VolumeMask, subGridBoundaryTreatment: SubGridBoundaryModes.InnerEdge); } // create artificial diffusion operator MultidimensionalArray DiffMtx; double[] DiffRhs; SpatialOperator dop; { double penaltyBase = this.LevelSetBasis.Degree + 2; penaltyBase = penaltyBase.Pow2(); dop = (new ArtificialViscosity(AcceptedMask, penaltyBase, GridDat.Cells.h_min, jCell, -1.0)).Operator(1); MsrMatrix _DiffMtx = new MsrMatrix(this.LevelSetMapping, this.LevelSetMapping); double[] _DiffRhs = new double[this.LevelSetMapping.LocalLength]; dop.ComputeMatrixEx(this.LevelSetMapping, new DGField[] { Phi, null, null }, this.LevelSetMapping, _DiffMtx, _DiffRhs, OnlyAffine: false, edgeQuadScheme: (new EdgeQuadratureScheme(domain: jCellGrid.AllEdgesMask)), volQuadScheme: (new CellQuadratureScheme(domain: jCellGrid.VolumeMask))); // extract matrix for 'jCell' DiffMtx = MultidimensionalArray.Create(N, N); DiffRhs = new double[N]; for (int n = 0; n < N; n++) { #if DEBUG int Lr; int[] row_cols = null; double[] row_vals = null; Lr = _DiffMtx.GetRow(i0G + n, ref row_cols, ref row_vals); for (int lr = 0; lr < Lr; lr++) { int ColIndex = row_cols[lr]; double Value = row_vals[lr]; Debug.Assert((ColIndex >= i0G && ColIndex < i0G + N) || (Value == 0.0), "Matrix is expected to be block-diagonal."); } #endif for (int m = 0; m < N; m++) { DiffMtx[n, m] = _DiffMtx[i0G + n, i0G + m]; } DiffRhs[n] = _DiffRhs[i0L + n]; } #if DEBUG var Test = DiffMtx.Transpose(); Test.Acc(-1.0, DiffMtx); Debug.Assert(Test.InfNorm() <= 1.0e-8); #endif } // find 'good' initial value by geometric solve AND // thresholds for the maximum an minimal value of Phi double Range = MaxAllowedPhi - MinAllowedPhi; MinAllowedPhi -= 0.1 * Range; MaxAllowedPhi += 0.1 * Range; // timestep for pseudo-timestepping double dt = 0.5 * this.GridDat.Cells.h_min[jCell] / (((double)(this.LevelSetBasis.Degree)).Pow2()); DGField[] PlotFields = new DGField[] { Phi, gradPhi[0], gradPhi[1], __DiffusionCoeff, __AcceptedMask }; //Tecplot.Tecplot.PlotFields(Params, "itt_0", "EllipicReinit", 0, 3); double[] PrevVal = new double[N]; double[] NextVal = new double[N]; Phi.Coordinates.GetRow(jCell, PrevVal); // pseudo-timestepping //if(jCell == 80) // Tecplot.Tecplot.PlotFields(PlotFields, "itt_0", "EllipicReinit", 0, 3); //Console.Write(" Local solve cell " + jCell + " ... "); bool converged = false; double DiffusionCoeff = 0; int IterGrowCount = 0; // number of iterations in which the residual grew double LastResi = double.NaN; for (int iIter = 0; iIter < 1000; iIter++) { //Console.Write(" Local solve iteration " + iIter + " ... "); PerformRKstep(dt, jCell, AcceptedMask, Phi, gradPhi, evo); __DiffusionCoeff.SetMeanValue(jCell, DiffusionCoeff); if (jCell == 80) { DiffusionCoeff = 0.1; } if (DiffusionCoeff > 0) { //Console.WriteLine(" Diffusion on."); double[] _DiffRhs = new double[this.LevelSetMapping.LocalLength]; dop.ComputeMatrixEx(this.LevelSetMapping, new DGField[] { Phi, gradPhi[0], gradPhi[1] }, this.LevelSetMapping, default(MsrMatrix), _DiffRhs, OnlyAffine: true, edgeQuadScheme: (new EdgeQuadratureScheme(domain: jCellGrid.AllEdgesMask)), volQuadScheme: (new CellQuadratureScheme(domain: CellMask.GetEmptyMask(this.GridDat)))); // extract matrix for 'jCell' for (int n = 0; n < N; n++) { DiffRhs[n] = _DiffRhs[i0L + n]; } PerformArtificialDiffusion(dt * DiffusionCoeff, jCell, Phi, DiffMtx, DiffRhs); } Phi.Coordinates.GetRow(jCell, NextVal); double resi = Math.Sqrt(GenericBlas.L2DistPow2(NextVal, PrevVal) / GenericBlas.L2NormPow2(PrevVal)); double[] A = NextVal; NextVal = PrevVal; PrevVal = A; if (iIter > 0 && resi > LastResi) { IterGrowCount++; } else { IterGrowCount = 0; } LastResi = resi; if (resi < 1.0e-10) { converged = true; break; } double maxPhi, minPhi; Phi.GetExtremalValuesInCell(out minPhi, out maxPhi, jCell); bool MinAlarm = minPhi < MinAllowedPhi; bool Maxalarm = maxPhi > MaxAllowedPhi; bool GrowAlarm = IterGrowCount > 4; bool IterAlarm = iIter >= 50; if (MinAlarm || Maxalarm || GrowAlarm) { // Diffusion coefficient should be increased if (DiffusionCoeff == 0) { DiffusionCoeff = 1.0e-2; } else { if (DiffusionCoeff < 1.0e3) { DiffusionCoeff *= 2; } } //Console.WriteLine(" increasing Diffusion: {0}, Alarms : {1}{2}{3}{4}", DiffusionCoeff, MinAlarm ? 1 : 0, Maxalarm ? 1 : 0, GrowAlarm ? 1 : 0, IterAlarm ? 1 : 0); } //if(jCell == 80 && iIter < 100) // Tecplot.Tecplot.PlotFields(PlotFields, "itt_" + (iIter + 1), "EllipicReinit", iIter + 1, 3); } return(converged); }
/// <summary> /// creates the spatial operator that consists only of component <paramref name="c"/> /// </summary> public static XSpatialOperatorMk2 XOperator(this IEquationComponent c, int DegreeOfNonlinearity = 1) { return(XOperator(c, QuadOrderFunc.NonLinear(DegreeOfNonlinearity))); }
/// <summary> /// creates the spatial operator that consists only of component <paramref name="c"/> /// </summary> public static XSpatialOperatorMk2 XOperator(this IEquationComponent c, IEnumerable <string> species, int DegreeOfNonlinearity = 1) { return(XOperator(c, species, QuadOrderFunc.NonLinear(DegreeOfNonlinearity))); }
/// <summary> /// Declaration of the spatial operator /// </summary> protected override SpatialOperator GetOperatorInstance(int D) { // instantiate boundary condition mapping // ====================================== boundaryCondMap = new IncompressibleBoundaryCondMap(this.GridData, this.Control.BoundaryValues, PhysicsMode.Incompressible); // instantiate operator // ==================== string[] CodName = (new[] { "ResidualMomentumX", "ResidualMomentumY", "ResidualMomentumZ" }).GetSubVector(0, D).Cat("ResidualConti"); var op = new SpatialOperator( __DomainVar: VariableNames.VelocityVector(D).Cat(VariableNames.Pressure), __ParameterVar: VariableNames.GravityVector(D), __CoDomainVar: CodName, QuadOrderFunc: QuadOrderFunc.NonLinear(2)); op.LinearizationHint = LinearizationHint.GetJacobiOperator; // Temporal Operator // ================= var TempOp = new ConstantTemporalOperator(op, 0.0); // init with entire diagonal set to 0.0 op.TemporalOperator = TempOp; for (int d = 0; d < D; d++) { TempOp.SetDiagonal(CodName[d], Control.Density); // set momentum equation entries to density } // Pressure Reference // ================== // if there is no Dirichlet boundary condition, // the mean value of the pressure is free: op.FreeMeanValue[VariableNames.Pressure] = !boundaryCondMap.DirichletPressureBoundary; // Momentum Equation // ================= // convective part: { for (int d = 0; d < D; d++) { var comps = op.EquationComponents[CodName[d]]; var ConvBulk = new LocalLaxFriedrichsConvection(D, boundaryCondMap, d, Control.Density); comps.Add(ConvBulk); // bulk component } } // pressure part: { for (int d = 0; d < D; d++) { var comps = op.EquationComponents[CodName[d]]; var pres = new PressureGradientLin_d(d, boundaryCondMap); comps.Add(pres); // bulk component } } // viscous part: { for (int d = 0; d < D; d++) { var comps = op.EquationComponents[CodName[d]]; double penalty_bulk = this.Control.PenaltySafety; var Visc = new swipViscosity_Term1(penalty_bulk, d, D, boundaryCondMap, ViscosityOption.ConstantViscosity, constantViscosityValue: Control.Viscosity); comps.Add(Visc); // bulk component GradUTerm } } // Continuity equation // =================== { for (int d = 0; d < D; d++) { var src = new Divergence_DerivativeSource(d, D); var flx = new Divergence_DerivativeSource_Flux(d, boundaryCondMap); op.EquationComponents[CodName[D]].Add(src); op.EquationComponents[CodName[D]].Add(flx); } //IBM_Op.EquationComponents["div"].Add(new PressureStabilization(1, 1.0 / this.Control.PhysicalParameters.mu_A)); } // Gravity parameter // ================= op.ParameterFactories.Add(delegate(IReadOnlyDictionary <string, DGField> DomainVarFields) { return(D.ForLoop(d => (VariableNames.Gravity_d(d), this.Gravity[d] as DGField))); }); // commit & return // =============== op.Commit(); return(op); }