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Ujesha Saigal
Join Date: Sep 2023
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I am trying to solve supersonic laminar flow over a flat plate with a mesh resolution of 2.5e-3 (1280000 nodes). Inlet Temperature is 300K, density is 1.225 kg/m^3 and velocity is 868 m/s. Reynold's number is 20000. I have tried changing CFL numbers to 5,10 and 1 but the value of Cp in the line plot is more than 700, which should be less than 1 in my case although the skin friction coefficient is nearly the same as compared to the Blasius analytical solution. I have read that in supersonic flow whatever outlet pressure we input is unnecessary because in the case of supersonic flow outlet pressure is extrapolated itself. I have attached my cfg file and mesh for review. Kindly let me know what is wrong with my file.
% SU2 configuration file % % Case description: Laminar flow over a flat plate with zero pressure gradient % % Author: Thomas D. Economon % % Institution: Stanford University % % Date: 2013.09.30 % % File Version 5.0.0 "Raven" % % % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % ------------- DIRECT, ADJOINT, AND LINEARIZED PROBLEM DEFINITION ------------% % % Physical governing equations (EULER, NAVIER_STOKES, % WAVE_EQUATION, HEAT_EQUATION, FEM_ELASTICITY, % POISSON_EQUATION) SOLVER= NAVIER_STOKES % % Specify turbulence model (NONE, SA, SA_NEG, SST) KIND_TURB_MODEL= NONE % % Mathematical problem (DIRECT, CONTINUOUS_ADJOINT) MATH_PROBLEM= DIRECT % % Restart solution (NO, YES) RESTART_SOL= NO % -------------------- COMPRESSIBLE FREE-STREAM DEFINITION --------------------% % % Mach number (non-dimensional, based on the free-stream values) MACH_NUMBER= 2.5 % % Angle of attack (degrees, only for compressible flows) AOA= 0.0 % % Side-slip angle (degrees, only for compressible flows) SIDESLIP_ANGLE= 0.0 % % Free-stream temperature (288.15 K by default) FREESTREAM_TEMPERATURE= 300 % % Reynolds number (non-dimensional, based on the free-stream values) REYNOLDS_NUMBER= 20000 % % Reynolds length (1 m by default) REYNOLDS_LENGTH= 1.2 % ---------------------- REFERENCE VALUE DEFINITION ---------------------------% % % Reference origin for moment computation REF_ORIGIN_MOMENT_X = 0.25 REF_ORIGIN_MOMENT_Y = 0.00 REF_ORIGIN_MOMENT_Z = 0.00 % % Reference length for pitching, rolling, and yawing non-dimensional moment REF_LENGTH= 1.0 % % Reference area for force coefficients (0 implies automatic calculation) REF_AREA= 0.3048 % -------------------- BOUNDARY CONDITION DEFINITION --------------------------% % % Navier-Stokes (no-slip), constant heat flux wall marker(s) (NONE = no marker) % Format: ( marker name, constant heat flux (J/m^2), ... ) MARKER_HEATFLUX= ( wall, 0.0 ) % % Navier-Stokes (no-slip), isothermal wall marker(s) (NONE = no marker) % Format: ( marker name, constant wall temperature (K), ... ) MARKER_ISOTHERMAL= ( NONE ) % % Symmetry boundary marker(s) (NONE = no marker) MARKER_SYM= ( symmetry ) % % Inlet boundary marker(s) (NONE = no marker) % Format: ( inlet marker, total temperature, total pressure, flow_direction_x, % flow_direction_y, flow_direction_z, ... ) where flow_direction is % a unit vector. MARKER_SUPERSONIC_INLET = (inlet, 300, 105472.5, 868.0, 0.0, 0.0) % % Outlet boundary marker(s) (NONE = no marker) % Format: ( outlet marker, back pressure (static), ... ) MARKER_OUTLET= (outlet, 90000) % % Marker(s) of the surface to be plotted or designed MARKER_PLOTTING= ( wall ) % % Marker(s) of the surface where the functional (Cd, Cl, etc.) will be evaluated MARKER_MONITORING= ( wall ) % ------------- COMMON PARAMETERS DEFINING THE NUMERICAL METHOD ---------------% % % Numerical method for spatial gradients (GREEN_GAUSS, WEIGHTED_LEAST_SQUARES) NUM_METHOD_GRAD= WEIGHTED_LEAST_SQUARES % % Courant-Friedrichs-Lewy condition of the finest grid CFL_NUMBER= 5 % % Adaptive CFL number (NO, YES) CFL_ADAPT= NO % % Parameters of the adaptive CFL number (factor down, factor up, CFL min value, % CFL max value ) CFL_ADAPT_PARAM= ( 0.1, 2.0, 100.0, 1e10 ) % % Number of total iterations ITER= 100000 % ------------------------ LINEAR SOLVER DEFINITION ---------------------------% % % Linear solver for implicit formulations (BCGSTAB, FGMRES) LINEAR_SOLVER= FGMRES % % Preconditioner of the Krylov linear solver (JACOBI, LINELET, LU_SGS) LINEAR_SOLVER_PREC= ILU % % Minimum error of the linear solver for implicit formulations LINEAR_SOLVER_ERROR= 1E-6 % % Max number of iterations of the linear solver for the implicit formulation LINEAR_SOLVER_ITER= 10 % -------------------------- MULTIGRID PARAMETERS -----------------------------% % % Multi-Grid Levels (0 = no multi-grid) MGLEVEL= 0 % % Multi-grid cycle (V_CYCLE, W_CYCLE, FULLMG_CYCLE) MGCYCLE= W_CYCLE % % Multi-grid pre-smoothing level MG_PRE_SMOOTH= ( 1, 2, 3, 3 ) % % Multi-grid post-smoothing level MG_POST_SMOOTH= ( 0, 0, 0, 0 ) % % Jacobi implicit smoothing of the correction MG_CORRECTION_SMOOTH= ( 0, 0, 0, 0 ) % % Damping factor for the residual restriction MG_DAMP_RESTRICTION= 0.9 % % Damping factor for the correction prolongation MG_DAMP_PROLONGATION= 0.9 % -------------------- FLOW NUMERICAL METHOD DEFINITION -----------------------% % % Convective numerical method (JST, LAX-FRIEDRICH, CUSP, ROE, AUSM, HLLC, % TURKEL_PREC, MSW) CONV_NUM_METHOD_FLOW= ROE % % Monotonic Upwind Scheme for Conservation Laws (TVD) in the flow equations. % Required for 2nd order upwind schemes (NO, YES) MUSCL_FLOW= NO % % Slope limiter (NONE, VENKATAKRISHNAN, VENKATAKRISHNAN_WANG, % BARTH_JESPERSEN, VAN_ALBADA_EDGE) SLOPE_LIMITER_FLOW= NONE % % Coefficient for the limiter (smooth regions) VENKAT_LIMITER_COEFF= 0.05 % % 2nd and 4th order artificial dissipation coefficients JST_SENSOR_COEFF= ( 0.5, 0.02 ) % % Time discretization (RUNGE-KUTTA_EXPLICIT, EULER_IMPLICIT, EULER_EXPLICIT) TIME_DISCRE_FLOW= EULER_IMPLICIT % --------------------------- CONVERGENCE PARAMETERS --------------------------% % % Convergence criteria (CAUCHY, RESIDUAL) CONV_FIELD= RMS_DENSITY % % Min value of the residual (log10 of the residual) CONV_RESIDUAL_MINVAL= -12 % % Start convergence criteria at iteration number CONV_STARTITER= 10 % % Number of elements to apply the criteria CONV_CAUCHY_ELEMS= 100 % % Epsilon to control the series convergence CONV_CAUCHY_EPS= 1E-6 % ------------------------- INPUT/OUTPUT INFORMATION --------------------------% % % Mesh input file MESH_FILENAME= lpus2.su2 % % Mesh input file format (SU2, CGNS, NETCDF_ASCII) MESH_FORMAT= SU2 % % Mesh output file MESH_OUT_FILENAME= mesh_out.su2 % % Restart flow input file SOLUTION_FILENAME= solution_flow.dat % % Restart adjoint input file SOLUTION_ADJ_FILENAME= solution_adj.dat % % Output file format (PARAVIEW, TECPLOT, STL) TABULAR_FORMAT= CSV % % Output file convergence history (w/o extension) CONV_FILENAME= history % % Output file restart flow RESTART_FILENAME= restart_flow.dat % % Output file restart adjoint RESTART_ADJ_FILENAME= restart_adj.dat % % Output file flow (w/o extension) variables VOLUME_FILENAME= flow % % Output file adjoint (w/o extension) variables VOLUME_ADJ_FILENAME= adjoint % % Output objective function gradient (using continuous adjoint) GRAD_OBJFUNC_FILENAME= of_grad.dat % % Output file surface flow coefficient (w/o extension) SURFACE_FILENAME= surface_flow % % Output file surface adjoint coefficient (w/o extension) SURFACE_ADJ_FILENAME= surface_adjoint % % % Screen output SCREEN_OUTPUT=(INNER_ITER, WALL_TIME, RMS_DENSITY, RMS_ENERGY, LIFT, DRAG) Last edited by ujesha; October 6, 2023 at 11:03. Reason: My presentation was not elaborate. |
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bigfoot
Join Date: Dec 2011
Location: Netherlands
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