Input File

Input File Parameter Definitions

The input file controls all operations performed by HiFiLES. Below is a [hopefully] comprehensive list of all inputs available for use in the code.

The general form for a parameter in the input file is:

parameter_name parameter_value

If the parameter requires a set of values, the format is:

parameter_name #_of_values value1 value2 ...

---

Solver Parameters

• equation

• 0 | Solve the full Euler/Navier-Stokes equations [default]
• 1 | Solve the scalar advection/diffusion equation

• viscous

• 0 | Inviscid [Euler equations] [default]
• 1 | Viscous [Navier-Stokes equations]

• riemann_solve_type: Inviscid Riemann solver to use at all element interface flux points

• 0 | Scalar diffusion [Rusanov] [default]
• 1 | Lax-Friedrich [for advection/diffusion only]
• 2 | Roe

• ic_form: Initial condition type

• 0 | Isentropic vortex test case
• 1 | Uniform flow [default]
• 2 | Sine wave

• test_case: Are we running a case with an analytical solution? If so, which one?

• 0 | No test case [default]
• 1 | Isentropic Vortex
• 2 | Advection-Equation [?]

• order: Order of basis polynomials
• dt_type: Which type of time-advancement

• 0 | Constant, user-supplied step size [default]
• 1 | Global minimum CFL-based time step (Must specify CFL)
• 2 | Element-local CFL-based time stepping (Must specify CFL)

• dt: Time step in non-dimensional units
• n_steps: Number of time steps [iterations] to perform
• adv_type: Time integration method

• 0 | Forward Euler
• 3 | Low-Storage 4th-order 5-stage Runge-Kutta

• tau: "tau" factor used in LDG flux

• 0 by default

• pen_fact: Penalty factor for LDG flux

• 0.5 by default

---

Restart Options

• restart_flag: Start from a restart file or no?

• 0 | No [default]
• 1 | Yes

• restart_iter: Iteration number to restart from (must match number in restart file name)
• n_restart_files: Number of restart files make up the case we are restarting (corresponds to the number of processors used when the restart file was made)

---

Mesh Options

• mesh_file: Name of the mesh file to use
• dx_cyclic: Length (in x-direction) of periodic domain

• Infinity by default [not a periodic domain]

• dy_cyclic: Length (in y-direction) of periodic domain

• Infinity by default [not a periodic domain]

• dz_cyclic: Length (in z-direction) of periodic domain

• Infinity by default [not a periodic domain]

---

LES Options

• LES: use a subgrid model or no?

• 0 | No [default]
• 1 | Yes

• filter_type: when using an SGS model based on filtering, choose the filter type.

• 0 | Vasilyev high-order commuting filter (available for quad/hex elements only)
• 1 | Discrete Gaussian (available for quad, hex and tri elements only)
• 2 | Modal Vandermonde (available for all element types except prisms)
• default | if nothing specified, a simple element-average filter is used

• filter_ratio: specify the ratio of filter width over element size. Enter any positive real.
• SGS model: specify the SGS model.

• 0 | Smagorinsky
• 1 | Wall Adapting Local Eddy Viscosity (WALE)
• 2 | WALE + Similarity Mixed (WSM)
• 3 | Spectral Vanishing Viscosity (SVV): simply filters the solution
• 4 | Bardina Similarity

• wall_model: specify the near-wall model.

• 0 | no model [default]
• 1 | Werner-Wengle model
• 2 | Breuer-Rodi 3-layer model

• wall_layer_thickness: specify the distance from a no-slip surface within which the wall model is applied. Enter any positive real.

---

Data Output Options

• p_res: Plotting resolution, number of "plot points" per direction in each cell
• write_type: File type for solution data output

• 0 | Paraview .vtu (VTK Unstructured) type [default]
• 1 | Tecplot

• data_file_name: Prefix to use for all output files ["Mesh" by default]
• n_diagnostic_fields: Number of additional calculated fields to output, followed by the names of the fields

• Example: 6 u v w energy pressure mach
• Available fields: u v w energy pressure mach vorticity q_criterion u_average v_average w_average sensor epsilon

• inters_cub_order: Order of cubature (quadrature) rule for integrating fields (i.e., pressure & viscous forces) over element interfaces (surfaces)
• volume_cub_order: Order of cubature (quadrature) rule for integrating fields over element volumes
• plot_freq: Frequency (in iterations) at which to output the solution
• restart_dump_freq: Frequency at which to output a restart file
• monitor_integrals_freq: Frequency at which to calculate all requested integral quantities
• monitor_res_freq: Frequency at which the residual is computed & output to the terminal
• monitor_cp_freq: Frequency at which the Cp on wall boundaries is output to a file

• 0 | No output [default]

• res_norm_type: Norm to use on the residual

• 0 | Infinity norm
• 1 | L1 norm
• 2 | L2 norm [default]

• error_norm_type: Norm to use on error (test cases with analytical solution)

• 0 | Infinity norm
• 1 | L1 norm
• 2 | L2 norm [default]

---

Element Parameters

• upts_type_tri: Solution points type for triangles

• 0

• fpts_type_tri: Flux points type for triangles

• 0

• vcjh_scheme_tri:

• 0 | use value of 'c' specified by user
• 1 | 'DG'-like scheme (c = 0)
• 2 | 'SD'-like scheme
• 3 | Huyhn scheme
• 4 | c+ scheme

• c_tri: Value of 'c' parameter [for vcjh_scheme_tri = 0]

• 0.0

• sparse_tri: Use sparse BLAS routines?

• 0 | Dense BLAS [default]
• 1 | Sparse BLAS

• upts_type_quad: Solution points type for quadrilaterals

• 0

• vcjh_scheme_quad: Flux points type for quadrilaterals

• 0

• eta_quad

• 0.0

• sparse_quad

• 0 | Dense BLAS [default]
• 1 | Sparse BLAS

• upts_type_hexa

• 0

• vcjh_scheme_hexa

• 0

• eta_hexa

• sparse_hexa

• 0

• upts_type_tet

• 1

• fpts_type_tet

• 0

• vcjh_scheme_tet

• 0

• eta_tet

• 0.0

• sparse_tet

• 0 | Dense BLAS [default]
• 1 | Sparse BLAS

• upts_type_pri_tri

• 0

• upts_type_pri_1d

• 0

• vcjh_scheme_pri_1d

• 0

• eta_pri

• 0.0

• sparse_pri

• 0 | Dense BLAS [default]
• 1 | Sparse BLAS

---

Fluid Parameters

• gamma: Ratio of specific heats

• 1.4 by default

• prandtl: Prandtl number

• 0.72 by defult

• R_gas: Ideal gas constant (J/kg-K)

• 286.9 by default

• mu_gas: Dynamic viscosity (kg/m-s)

• 1.827E-05 by default

• S_gas: "S" from Sutherland's Law for viscosity

• 120 by defult

• T_gas: Temperature of the gas for Sutherland's Law (Kelvin)

• 291.15 by default

• fix_vis // 0: Sutherland's law, 1: Constant viscosity

• 0 | Sutherland's Law [default]
• 1 | Constant viscosity

---

Boundary conditions

Viscous Boundary Conditions - Used only for viscous cases

• Mach_free_stream: Mach number of free-stream flow
• nx_free_stream: normalized x-component of free-stream flow [unit normal component]
• ny_free_stream: normalized y-component of free-stream flow
• nz_free_stream: normalized z-component of free-stream flow
• Re_free_stream: Reynolds number of free-stream flow
• L_free_stream : Reference length corresponding to the chosen Re (i.e. chord length of airfoil)

• 1 by default

• T_free_stream: Temperature of free-stream flow (Kelvin)

• 300 by default

• T_wall: Temperature of isothermal wall

• 300 by default

• Mach_wall: For moving wall, to calculate velocity magnitude of wall motion [don't use this]

• 0.0 by default

• nx_wall: For moving wall [don't use this]
• ny_wall: For moving wall [don't use this]
• nz_wall: For moving wall [don't use this]

Inviscid Boundary Conditions - Used only for inviscid cases

• rho_bound: Density of free-stream
• u_bound: x-component of velocity
• v_bound: y-component of velocity
• w_bound: z-component of velocity
• p_bound: Pressure of free-stream

Initial Conditions

These are set equal to the prescribed boundary conditions by default

These initial conditions are used only for inviscid flows:

• rho_c_ic Initial condition on density
• u_c_ic Initial condition on x-velocity
• v_c_ic Initial condition on y-velocity
• w_c_ic Initial condition on z-velocity
• p_c_ic: Initial condition on pressure

The following initial conditions are utilized only for viscous flows:

• Mach_c_ic: Initial Mach number of fluid
• nx_c_ic: Initial x-component of fluid motion
• ny_c_ic: Initial y-component of fluid motion
• nz_c_ic: Initial z-component of fluid motion
• Re_c_ic: Reynolds number initial condition
• T_c_ic: Initial condition on temperature

---

Shock Capturing / Filtering Options

• artif_only: To run inviscid case with artificial viscosity (mu = 0), set this to 1 - don't use it for concentration method
• artif_type: Type of artificial viscosity

• 0 | Persson's method
• 1 | Concentration method

• ArtifOn: Turn artificial viscosity on/off

• 0 [off] by default

• epsilon0
• s0: Sensor threshold value (values of sensor > s0 will be filtered) (typically of order 1)
• kappa

---

Mesh Deformation Options

• motion_flag: Are we running a moving-mesh case? If so, what method?

• 0 | No motion [default]
• 1 | Linear-elasticity method
• 2 | Rigid movement
• 3 | Sin/Cos perturbations test case (see Persson, DG on deforming domains)
• 4 | Blending functions

• GCL_flag: Solve the Geometric Conservation Law? [not working yet]

• 0 | No [default]
• 1 | Yes
• n_deform_iters: For linear elasticity method, number of iterations to perform during each time-step's deformation process
• 1 by default

• mesh_output_freq: Frequency at which to output mesh to file (-1: use plot_freq)

• -1 | Use plot_freq
• No output by default

• mesh_output_format: Format for mesh file output

• 0 | Gambit [not implemented yet]
• 1 | Gmsh [default]

• blend_dist: Distance over which to blend motion for blending method
• moving_boundaries: Control periodic motion of multiple boundaries (see below)

Format of moving_boundaries parameter: {n_moving_bnds}
{bnd name 1} {motion type 1} {motion params 1}
{bnd name 2} {motion type 2} {motion params 2}
...etc.
Boundary name: name (in mesh file) of moving boundary
Motion type: motion params:

• 0: Constant velocity [x-velocity,y-velocity,z-velocity]
• 1: Periodic motion [Ax,Ay,Az,Atheta,Wx,Wy,Wz,Wtheta]

• (x = Axsin(2piWxt), y = Aysin(2piWyt), z = ...)

For Example:
Slip_Wall 1 -2 2 0 0 2 2 0 0

Wave Equation parameters

For Advection/Diffusion Equation Only

• wave_speed_x
• wave_speed_y
• wave_speed_z
• lambda: Flux parameter, in range [0,1]

• 0 = central
• 1 = upwind