1 // SPDX-FileCopyrightText: Copyright (c) 2017-2024, HONEE contributors. 2 // SPDX-License-Identifier: Apache-2.0 OR BSD-2-Clause 3 4 /// @file 5 /// Utility functions for setting up Blasius Boundary Layer 6 7 #include "../qfunctions/blasius.h" 8 9 #include <ceed.h> 10 #include <petscdm.h> 11 #include <petscdt.h> 12 13 #include <differential_filter.h> 14 #include <navierstokes.h> 15 #include "stg_shur14.h" 16 17 PetscErrorCode CompressibleBlasiusResidual(SNES snes, Vec X, Vec R, void *ctx) { 18 const BlasiusContext blasius = (BlasiusContext)ctx; 19 const PetscScalar *Tf, *Th; // Chebyshev coefficients 20 PetscScalar *r, f[4], h[4]; 21 PetscInt N = blasius->n_cheb; 22 State S_infty = blasius->S_infty; 23 CeedScalar U_infty = Norm3(S_infty.Y.velocity); 24 NewtonianIGProperties gas = blasius->newt_ctx.gas; 25 26 PetscFunctionBeginUser; 27 PetscScalar Ma = Mach(gas, S_infty.Y.temperature, U_infty), Pr = Prandtl(gas), gamma = HeatCapacityRatio(gas); 28 29 PetscCall(VecGetArrayRead(X, &Tf)); 30 Th = Tf + N; 31 PetscCall(VecGetArray(R, &r)); 32 33 // Left boundary conditions f = f' = 0 34 ChebyshevEval(N, Tf, -1., blasius->eta_max, f); 35 r[0] = f[0]; 36 r[1] = f[1]; 37 38 // f - right end boundary condition 39 ChebyshevEval(N, Tf, 1., blasius->eta_max, f); 40 r[2] = f[1] - 1.; 41 42 for (int i = 0; i < N - 3; i++) { 43 ChebyshevEval(N, Tf, blasius->X[i], blasius->eta_max, f); 44 ChebyshevEval(N - 1, Th, blasius->X[i], blasius->eta_max, h); 45 // mu and rho generally depend on h. 46 // We naively assume constant mu. 47 // For an ideal gas at constant pressure, density is inversely proportional to enthalpy. 48 // The *_tilde values are *relative* to their freestream values, and we proved first derivatives here. 49 const PetscScalar mu_tilde[2] = {1, 0}; 50 const PetscScalar rho_tilde[2] = {1 / h[0], -h[1] / PetscSqr(h[0])}; 51 const PetscScalar mu_rho_tilde[2] = { 52 mu_tilde[0] * rho_tilde[0], 53 mu_tilde[1] * rho_tilde[0] + mu_tilde[0] * rho_tilde[1], 54 }; 55 r[3 + i] = 2 * (mu_rho_tilde[0] * f[3] + mu_rho_tilde[1] * f[2]) + f[2] * f[0]; 56 r[N + 2 + i] = (mu_rho_tilde[0] * h[2] + mu_rho_tilde[1] * h[1]) + Pr * f[0] * h[1] + Pr * (gamma - 1) * mu_rho_tilde[0] * PetscSqr(Ma * f[2]); 57 } 58 59 // h - left end boundary condition 60 ChebyshevEval(N - 1, Th, -1., blasius->eta_max, h); 61 r[N] = h[0] - blasius->T_wall / S_infty.Y.temperature; 62 63 // h - right end boundary condition 64 ChebyshevEval(N - 1, Th, 1., blasius->eta_max, h); 65 r[N + 1] = h[0] - 1.; 66 67 // Restore vectors 68 PetscCall(VecRestoreArrayRead(X, &Tf)); 69 PetscCall(VecRestoreArray(R, &r)); 70 PetscFunctionReturn(PETSC_SUCCESS); 71 } 72 73 PetscErrorCode ComputeChebyshevCoefficients(BlasiusContext blasius) { 74 SNES snes; 75 Vec sol, res; 76 PetscReal *w; 77 PetscInt N = blasius->n_cheb; 78 SNESConvergedReason reason; 79 const PetscScalar *cheb_coefs; 80 81 PetscFunctionBeginUser; 82 // Allocate memory 83 PetscCall(PetscMalloc2(N - 3, &blasius->X, N - 3, &w)); 84 PetscCall(PetscDTGaussQuadrature(N - 3, -1., 1., blasius->X, w)); 85 86 // Snes solve 87 PetscCall(SNESCreate(PETSC_COMM_SELF, &snes)); 88 PetscCall(VecCreate(PETSC_COMM_SELF, &sol)); 89 PetscCall(VecSetSizes(sol, PETSC_DECIDE, 2 * N - 1)); 90 PetscCall(VecSetFromOptions(sol)); 91 // Constant relative enthalpy 1 as initial guess 92 PetscCall(VecSetValue(sol, N, 1., INSERT_VALUES)); 93 PetscCall(VecDuplicate(sol, &res)); 94 PetscCall(SNESSetFunction(snes, res, CompressibleBlasiusResidual, blasius)); 95 PetscCall(SNESSetOptionsPrefix(snes, "chebyshev_")); 96 PetscCall(SNESSetFromOptions(snes)); 97 PetscCall(SNESSolve(snes, NULL, sol)); 98 PetscCall(SNESGetConvergedReason(snes, &reason)); 99 PetscCheck(reason >= 0, PETSC_COMM_WORLD, PETSC_ERR_CONV_FAILED, "The Chebyshev solve failed."); 100 101 // Assign Chebyshev coefficients 102 PetscCall(VecGetArrayRead(sol, &cheb_coefs)); 103 for (int i = 0; i < N; i++) blasius->Tf_cheb[i] = cheb_coefs[i]; 104 for (int i = 0; i < N - 1; i++) blasius->Th_cheb[i] = cheb_coefs[i + N]; 105 106 // Destroy objects 107 PetscCall(PetscFree2(blasius->X, w)); 108 PetscCall(VecDestroy(&sol)); 109 PetscCall(VecDestroy(&res)); 110 PetscCall(SNESDestroy(&snes)); 111 PetscFunctionReturn(PETSC_SUCCESS); 112 } 113 114 static PetscErrorCode BlasiusInflowBCSetup_CreateIFunctionQF(BCDefinition bc_def, CeedQFunction *qf) { 115 HoneeBCStruct honee_bc; 116 117 PetscFunctionBeginUser; 118 PetscCall(BCDefinitionGetContext(bc_def, &honee_bc)); 119 PetscCall(HoneeBCCreateIFunctionQF(bc_def, Blasius_Inflow, Blasius_Inflow_loc, honee_bc->qfctx, qf)); 120 PetscFunctionReturn(PETSC_SUCCESS); 121 } 122 123 static PetscErrorCode BlasiusInflowBCSetup_CreateIJacobianQF(BCDefinition bc_def, CeedQFunction *qf) { 124 HoneeBCStruct honee_bc; 125 126 PetscFunctionBeginUser; 127 PetscCall(BCDefinitionGetContext(bc_def, &honee_bc)); 128 PetscCall(HoneeBCCreateIJacobianQF(bc_def, Blasius_Inflow_Jacobian, Blasius_Inflow_Jacobian_loc, honee_bc->qfctx, qf)); 129 PetscFunctionReturn(PETSC_SUCCESS); 130 } 131 132 PetscErrorCode NS_BLASIUS(ProblemData problem, DM dm, void *ctx) { 133 Honee honee = *(Honee *)ctx; 134 MPI_Comm comm = honee->comm; 135 Ceed ceed = honee->ceed; 136 PetscBool use_stg = PETSC_FALSE; 137 BlasiusContext blasius_ctx; 138 NewtonianIdealGasContext newtonian_ig_ctx; 139 CeedQFunctionContext blasius_qfctx; 140 141 PetscFunctionBeginUser; 142 PetscCall(NS_NEWTONIAN_IG(problem, dm, ctx)); 143 144 // ------------------------------------------------------ 145 // SET UP Blasius 146 // ------------------------------------------------------ 147 problem->ics = (HoneeQFSpec){.qf_func_ptr = ICsBlasius, .qf_loc = ICsBlasius_loc, .qfctx = problem->ics.qfctx}; 148 149 CeedScalar U_inf = 40; // m/s 150 CeedScalar T_inf = 288.; // K 151 CeedScalar T_wall = 288.; // K 152 CeedScalar delta0 = 4.2e-3; // m 153 CeedScalar P_inf = 1.01e5; // Pa 154 PetscInt N = 20; // Number of Chebyshev terms 155 PetscBool weakT = PETSC_FALSE; // weak density or temperature 156 PetscBool P0_set; 157 158 PetscOptionsBegin(comm, NULL, "Options for BLASIUS problem", NULL); 159 PetscCall(PetscOptionsBool("-weakT", "Change from rho weak to T weak at inflow", NULL, weakT, &weakT, NULL)); 160 PetscCall(PetscOptionsScalar("-velocity_infinity", "Velocity at boundary layer edge", NULL, U_inf, &U_inf, NULL)); 161 PetscCall(PetscOptionsScalar("-temperature_infinity", "Temperature at boundary layer edge", NULL, T_inf, &T_inf, NULL)); 162 PetscCall(PetscOptionsHasName(NULL, NULL, "-P0", &P0_set)); // For maintaining behavior of -P0 flag (which is deprecated) 163 PetscCall(PetscOptionsDeprecated("-P0", "-pressure_infinity", "libCEED 0.12.0", 164 "Use -pressure_infinity to set pressure at boundary layer edge and -idl_pressure to set the IDL reference " 165 "pressure")); 166 PetscCall(PetscOptionsScalar("-pressure_infinity", "Pressure at boundary layer edge", NULL, P_inf, &P_inf, NULL)); 167 PetscCall(PetscOptionsScalar("-temperature_wall", "Temperature at wall", NULL, T_wall, &T_wall, NULL)); 168 PetscCall(PetscOptionsScalar("-delta0", "Boundary layer height at inflow", NULL, delta0, &delta0, NULL)); 169 PetscCall(PetscOptionsInt("-n_chebyshev", "Number of Chebyshev terms", NULL, N, &N, NULL)); 170 PetscCheck(3 <= N && N <= BLASIUS_MAX_N_CHEBYSHEV, comm, PETSC_ERR_ARG_OUTOFRANGE, "-n_chebyshev %" PetscInt_FMT " must be in range [3, %d]", N, 171 BLASIUS_MAX_N_CHEBYSHEV); 172 PetscCall(PetscOptionsBool("-stg_use", "Use STG inflow boundary condition", NULL, use_stg, &use_stg, NULL)); 173 PetscOptionsEnd(); 174 175 Units units = honee->units; 176 177 T_inf *= units->Kelvin; 178 T_wall *= units->Kelvin; 179 P_inf *= units->Pascal; 180 U_inf *= units->meter / units->second; 181 delta0 *= units->meter; 182 183 // Some properties depend on parameters from NewtonianIdealGas 184 PetscCallCeed(ceed, CeedQFunctionContextGetData(problem->apply_vol_rhs.qfctx, CEED_MEM_HOST, &newtonian_ig_ctx)); 185 186 StatePrimitive Y_inf = { 187 .pressure = P_inf, .velocity = {U_inf, 0, 0}, 188 .temperature = T_inf 189 }; 190 State S_infty = StateFromPrimitive(newtonian_ig_ctx->gas, Y_inf); 191 192 PetscCall(PetscNew(&blasius_ctx)); 193 blasius_ctx->weakT = weakT; 194 blasius_ctx->T_wall = T_wall; 195 blasius_ctx->delta0 = delta0; 196 blasius_ctx->S_infty = S_infty; 197 blasius_ctx->n_cheb = N; 198 blasius_ctx->implicit = honee->phys->implicit; 199 if (P0_set) newtonian_ig_ctx->idl_pressure = P_inf; // For maintaining behavior of -P0 flag (which is deprecated) 200 blasius_ctx->newt_ctx = *newtonian_ig_ctx; 201 202 { 203 PetscReal domain_min[3], domain_max[3]; 204 PetscCall(DMGetBoundingBox(dm, domain_min, domain_max)); 205 blasius_ctx->x_inflow = domain_min[0]; 206 blasius_ctx->eta_max = 5 * domain_max[1] / blasius_ctx->delta0; 207 } 208 PetscBool diff_filter_mms = PETSC_FALSE; 209 PetscCall(PetscOptionsGetBool(NULL, NULL, "-diff_filter_mms", &diff_filter_mms, NULL)); 210 if (!use_stg && !diff_filter_mms) PetscCall(ComputeChebyshevCoefficients(blasius_ctx)); 211 212 PetscCallCeed(ceed, CeedQFunctionContextRestoreData(problem->apply_vol_rhs.qfctx, &newtonian_ig_ctx)); 213 214 PetscCallCeed(ceed, CeedQFunctionContextCreate(honee->ceed, &blasius_qfctx)); 215 PetscCallCeed(ceed, CeedQFunctionContextSetData(blasius_qfctx, CEED_MEM_HOST, CEED_USE_POINTER, sizeof(*blasius_ctx), blasius_ctx)); 216 PetscCallCeed(ceed, CeedQFunctionContextSetDataDestroy(blasius_qfctx, CEED_MEM_HOST, FreeContextPetsc)); 217 218 PetscCallCeed(ceed, CeedQFunctionContextDestroy(&problem->ics.qfctx)); 219 problem->ics.qfctx = blasius_qfctx; 220 if (use_stg) { 221 PetscCall(SetupStg(comm, dm, problem, honee, weakT, S_infty.Y.temperature, S_infty.Y.pressure)); 222 } else if (diff_filter_mms) { 223 PetscCall(DifferentialFilterMmsICSetup(honee)); 224 } else { 225 PetscCheck((honee->phys->state_var == STATEVAR_CONSERVATIVE) || (honee->app_ctx->test_type == TESTTYPE_DIFF_FILTER), honee->comm, 226 PETSC_ERR_ARG_INCOMP, "Can only use conservative variables with Blasius and weak inflow"); 227 for (PetscCount b = 0; b < problem->num_bc_defs; b++) { 228 BCDefinition bc_def = problem->bc_defs[b]; 229 const char *name; 230 231 PetscCall(BCDefinitionGetInfo(bc_def, &name, NULL, NULL)); 232 if (!strcmp(name, "inflow")) { 233 HoneeBCStruct honee_bc; 234 235 PetscCall(PetscNew(&honee_bc)); 236 PetscCallCeed(ceed, CeedQFunctionContextReferenceCopy(blasius_qfctx, &honee_bc->qfctx)); 237 honee_bc->honee = honee; 238 honee_bc->num_comps_jac_data = 0; 239 PetscCall(BCDefinitionSetContext(bc_def, (PetscCtxDestroyFn *)HoneeBCDestroy, honee_bc)); 240 241 PetscCall(BCDefinitionSetIFunction(bc_def, BlasiusInflowBCSetup_CreateIFunctionQF, HoneeBCAddIFunctionOp)); 242 PetscCall(BCDefinitionSetIJacobian(bc_def, BlasiusInflowBCSetup_CreateIJacobianQF, HoneeBCAddIJacobianOp)); 243 } 244 } 245 } 246 PetscFunctionReturn(PETSC_SUCCESS); 247 } 248