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Anomaly in Mach Flow Behavior with SST Turbulence Model |
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March 26, 2024, 03:22 |
Anomaly in Mach Flow Behavior with SST Turbulence Model
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Kuan-Lin Chen
Join Date: Sep 2016
Location: Taiwan
Posts: 10
Rep Power: 10 |
Hello everyone,
I'm currently working on validating the case of Axisymmetric Shock Wave Boundary Layer Interaction near M=7 (https://turbmodels.larc.nasa.gov/axiswblim7_val.html). However, I'm encountering an anomaly with the Mach flow when using the SST turbulence model. As indicated in my input .cfg file, the freestream Mach is set to 7.11, but the results show a lower value. mach_problem_SST.jpg However, when I switch to the SA turbulence model, the Mach returns to 7.11. Do you have any suggestions or insights? Or perhaps I've overlooked something? Your input would be greatly appreciated. Thank you. Code:
% ------------- DIRECT, ADJOINT, AND LINEARIZED PROBLEM DEFINITION ------------% % % Physical governing equations (EULER, NAVIER_STOKES, % WAVE_EQUATION, HEAT_EQUATION, FEM_ELASTICITY, % POISSON_EQUATION) SOLVER= RANS % % Specify turbulence model (NONE, SA, SA_NEG, SST) KIND_TURB_MODEL= SST % % Specify versions/corrections of the SST model (V2003m, V1994m, VORTICITY, KATO_LAUNDER, UQ, SUSTAINING) SST_OPTIONS= V2003m % Mathematical problem (DIRECT, CONTINUOUS_ADJOINT) MATH_PROBLEM= DIRECT % % % Axisymmetric simulation, only compressible flows (NO, YES) AXISYMMETRIC= NO % Restart solution (NO, YES) RESTART_SOL= NO % -------------------- COMPRESSIBLE FREE-STREAM DEFINITION --------------------% % % Mach number (non-dimensional, based on the free-stream values) MACH_NUMBER=7.11 % % Angle of attack (degrees, only for compressible flows) AOA= 0.0 % % Side-slip angle (degrees, only for compressible flows) SIDESLIP_ANGLE= 0.0 % % Init option to choose between Reynolds (default) or thermodynamics quantities % for initializing the solution (REYNOLDS, TD_CONDITIONS) INIT_OPTION= REYNOLDS % % Free-stream option to choose between density and temperature (default) for % initializing the solution (TEMPERATURE_FS, DENSITY_FS) FREESTREAM_OPTION= TEMPERATURE_FS % % Free-stream temperature (288.15 K by default) FREESTREAM_TEMPERATURE= 80 % % Reynolds number (non-dimensional, based on the free-stream values) REYNOLDS_NUMBER= 57060 % % Reynolds length (1 m, 1 inch by default) REYNOLDS_LENGTH= 0.01 % ---- IDEAL GAS, POLYTROPIC, VAN DER WAALS AND PENG ROBINSON CONSTANTS -------% % % Different gas model (STANDARD_AIR, IDEAL_GAS, VW_GAS, PR_GAS) FLUID_MODEL= STANDARD_AIR % % Ratio of specific heats (1.4 default and the value is hardcoded % for the model STANDARD_AIR) GAMMA_VALUE= 1.4 % % Specific gas constant (287.058 J/kg*K default and this value is hardcoded % for the model STANDARD_AIR) GAS_CONSTANT= 287.058 % --------------------------- VISCOSITY MODEL ---------------------------------% % % Viscosity model (SUTHERLAND, CONSTANT_VISCOSITY). VISCOSITY_MODEL= SUTHERLAND % % Sutherland Viscosity Ref (1.716E-5 default value for AIR SI) MU_REF= 1.716E-5 % % Sutherland Temperature Ref (273.15 K default value for AIR SI) MU_T_REF= 273.15 % % Sutherland constant (110.4 default value for AIR SI) SUTHERLAND_CONSTANT= 110.4 % --------------------------- THERMAL CONDUCTIVITY MODEL ----------------------% % % Conductivity model (CONSTANT_CONDUCTIVITY, CONSTANT_PRANDTL). CONDUCTIVITY_MODEL= CONSTANT_PRANDTL % % Laminar Prandtl number (0.72 (air), only for CONSTANT_PRANDTL) PRANDTL_LAM= 0.72 % % Turbulent Prandtl number (0.9 (air), only for CONSTANT_PRANDTL) PRANDTL_TURB= 0.90 % ---------------------- REFERENCE VALUE DEFINITION ---------------------------% % % Reference origin for moment computation REF_ORIGIN_MOMENT_X = 0.0 REF_ORIGIN_MOMENT_Y = 0.00 REF_ORIGIN_MOMENT_Z = 0.00 % % Reference length for pitching, rolling, and yawing non-dimensional moment %REF_LENGTH= 0.1015 % % Reference area for force coefficients (0 implies automatic calculation) %REF_AREA= 0.03236555 % % Compressible flow non-dimensionalization (DIMENSIONAL, FREESTREAM_PRESS_EQ_ONE, % FREESTREAM_VEL_EQ_MACH, FREESTREAM_VEL_EQ_ONE) REF_DIMENSIONALIZATION= DIMENSIONAL % -------------------- BOUNDARY CONDITION DEFINITION --------------------------% % % Navier-Stokes wall boundary marker(s) (NONE = no marker) %MARKER_HEATFLUX= ( Wall,0.0 ) % % Format: ( marker name, constant wall temperature (K), ... ) MARKER_ISOTHERMAL= ( Wall, 311 ) % Far-field boundary marker(s) (NONE = no marker) MARKER_FAR= ( FarField ) % % Symmetry boundary marker(s) (NONE = no marker) %MARKER_SYM= ( Symmetry ) % % 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= GREEN_GAUSS % % Courant-Friedrichs-Lewy condition of the finest grid CFL_NUMBER= 0.1 % % Adaptive CFL number (NO, YES) CFL_ADAPT= YES % % Parameters of the adaptive CFL number (factor down, factor up, CFL min value, % CFL max value ) CFL_ADAPT_PARAM= ( 0.1, 1.5, 0.05, 10, 0.001 ) % % Runge-Kutta alpha coefficients RK_ALPHA_COEFF= ( 0.66667, 0.66667, 1.000000 ) % % Number of total iterations ITER= 999999 %ITER= 10 % ------------------------ LINEAR SOLVER DEFINITION ---------------------------% % % Linear solver for the implicit (or discrete adjoint) formulation (BCGSTAB, FGMRES) LINEAR_SOLVER= FGMRES % % Preconditioner of the Krylov linear solver (NONE, JACOBI, LINELET,ILU) LINEAR_SOLVER_PREC= ILU % % Min error of the linear solver for the implicit formulation LINEAR_SOLVER_ERROR= 1E-6 % % Max number of iterations of the linear solver for the implicit formulation LINEAR_SOLVER_ITER= 20 % -------------------------- MULTIGRID PARAMETERS -----------------------------% % % Multi-Grid Levels (0 = no multi-grid) MGLEVEL= 0 % % Multi-grid cycle (V_CYCLE, W_CYCLE, FULLMG_CYCLE) MGCYCLE= V_CYCLE % % Multi-grid pre-smoothing level MG_PRE_SMOOTH= ( 1, 1, 1, 1 ) % % 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= 0.7 % % Damping factor for the correction prolongation MG_DAMP_PROLONGATION= 0.7 % -------------------- FLOW NUMERICAL METHOD DEFINITION -----------------------% % % Convective numerical method (JST, LAX-FRIEDRICH, CUSP, ROE, AUSM, HLLC, % TURKEL_PREC, MSW) CONV_NUM_METHOD_FLOW= ROE % ENTROPY_FIX_COEFF= 0.05 % % Spatial numerical order integration (1ST_ORDER, 2ND_ORDER, 2ND_ORDER_LIMITER) MUSCL_FLOW= YES % % Slope limiter (NONE, VENKATAKRISHNAN, VENKATAKRISHNAN_WANG, % BARTH_JESPERSEN, VAN_ALBADA_EDGE) SLOPE_LIMITER_FLOW= VENKATAKRISHNAN % % Coefficient for the Venkat's limiter (upwind scheme). A larger values decrease % the extent of limiting, values approaching zero cause % lower-order approximation to the solution (0.05 by default) VENKAT_LIMITER_COEFF= 0.05 % % % Time discretization (RUNGE-KUTTA_EXPLICIT, EULER_IMPLICIT, EULER_EXPLICIT) TIME_DISCRE_FLOW= EULER_IMPLICIT % -------------------- TURBULENT NUMERICAL METHOD DEFINITION ------------------% % % Convective numerical method (SCALAR_UPWIND) CONV_NUM_METHOD_TURB= SCALAR_UPWIND % % Monotonic Upwind Scheme for Conservation Laws (TVD) in the turbulence equations. % Required for 2nd order upwind schemes (NO, YES) MUSCL_TURB= NO % % Slope limiter (VENKATAKRISHNAN, MINMOD) SLOPE_LIMITER_TURB= VENKATAKRISHNAN % % Time discretization (EULER_IMPLICIT) TIME_DISCRE_TURB= EULER_IMPLICIT % --------------------------- CONVERGENCE PARAMETERS --------------------------% % % Convergence criteria (CAUCHY, RESIDUAL) CONV_FIELD= RMS_DENSITY % % Min value of the residual (log10 of the residual) CONV_RESIDUAL_MINVAL= -8 % % 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= 2D_grid_m.su2 %DV_KIND= SCALE %DV_PARAM= ( 1.0 ) %DV_MARKER= ( Wall, FarField ) %DV_VALUE = 0.01 % % Mesh input file format (SU2, CGNS, NETCDF_ASCII) MESH_FORMAT= SU2 % % Mesh output file %MESH_OUT_FILENAME= mesh_2D_grid_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 % % Possible formats : (TECPLOT_ASCII, TECPLOT, SURFACE_TECPLOT_ASCII, % SURFACE_TECPLOT, CSV, SURFACE_CSV, PARAVIEW_ASCII, PARAVIEW_LEGACY, SURFACE_PARAVIEW_ASCII, % SURFACE_PARAVIEW_LEGACY, PARAVIEW, SURFACE_PARAVIEW, RESTART_ASCII, RESTART, CGNS, SURFACE_CGNS, STL_ASCII, STL_BINARY) % default : (RESTART, SURFACE_TECPLOT, SURFACE_PARAVIEW) %OUTPUT_FILES= (RESTART, TECPLOT,SURFACE_TECPLOT) % 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_NU_TILDE, LIFT, DRAG) SCREEN_OUTPUT= (INNER_ITER,RMS_DENSITY,RMS_MOMENTUM-X,RMS_MOMENTUM-Y,RMS_TKE,RMS_DISSIPATION,LINSOL_ITER,LINSOL_RESIDUAL,FORCE_Y, FORCE_X) % Writing solution frequency OUTPUT_WRT_FREQ= 250 % % Writing convergence history frequency SCREEN_WRT_FREQ_INNER= 1 % %WRT_RESIDUALS = YES %VOLUME_OUTPUT= (RESIDUAL,LIMITERS) VOLUME_OUTPUT= (COORDINATES, SOLUTION, PRIMITIVE) % %WRT_LIMITERS = YES % WRT_FORCES_BREAKDOWN= YES |
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