[Salome CFD/Code Saturne] Heated Square Cavity Tutorial

This is a tutorial to show you how to setup the heated square cavity tutorial with Salome-CFD and Code Saturne.

Here’s the video:

This tutorial is using Code_Saturne 7.0.4. Some differences might appear if you are using an older or more recent version.

The PDF for this tutorial is available here:

https://www.code-saturne.org/cms/web/sites/default/files/07_HeatedSquareCavityFlow.pdf

The code and model is available here: https://github.com/CyprienRusu/Feaforall/tree/master/Code%20Saturne%20Tutorials/heated_cavity

Main Steps of this Simulation

Create the Model and the Mesh

1 m x 1 m x 0.01 m
element size = 0.0125
number of elements = 80
Create groups

In Code_Saturne GUI

Define the Mesh
Mesh -> Boundary Zones

Incompressible
Laminar

Body Forces > Gravity -9.81 m/s2 for gy

Volume Conditions -> Activate Initialisation

Density> User Law

Reference = 1.2039 kg/m3

Viscosity

Reference = 1.83e-5 Pa.s

Specific Heat

Cp 1004.84 J/kg/K

Thermal Conductivity

Reference Value Lambda = 0.0259 W/m/K

Boundary conditions

Symmetry Plane -> Symmetry
Others-> Walls

Symmetry planes —> nothing to setup
Adiabatic Walls —> Prescribed Flux = 0
Hot Wall —> Prescribed Value = 303.15
Cold Wall —> Prescribed Value = 293.15

Time Settings

Time varying (Adaptive)
Velocity-Pressure Algorithm SIMPLEC
Number of Time steps = 450

User Routines:

Place the following file in the SRC folder (Link)

Here’s the code for the cs_user_physical_properties user routine (C Language):

void
cs_user_physical_properties(cs_domain_t   *domain)
{
  CS_NO_WARN_IF_UNUSED(domain);

  /* Check fields exists */
  if (CS_F_(rho) == NULL)
    bft_error(__FILE__, __LINE__, 0,_("error rho not variable\n"));

  const cs_lnum_t n_cells = cs_glob_mesh->n_cells;

  cs_real_t *cpro_rho = CS_F_(rho)->val;
  const cs_real_t *cvar_temp = CS_F_(t)->val;
  const cs_real_t *grav = cs_glob_physical_constants->gravity;

  const cs_real_t ro0 = cs_glob_fluid_properties->ro0;
  const cs_real_t cp0 = cs_glob_fluid_properties->cp0;
   const cs_real_t lambda0 = cs_glob_fluid_properties->lambda0;
  const cs_real_t viscl0 = cs_glob_fluid_properties->viscl0;

  /* Value of the imposed Rayleigh number */
  const cs_real_t Ra = 1.e6;

  /* The givens of the problem */
  const cs_real_t L = 1.0, T_hot = 303.15, T_cold = 293.15;
  const cs_real_t g = sqrt(cs_math_sq(grav[0]) + cs_math_sq(grav[1])
                    + cs_math_sq(grav[2]));

  const cs_real_t beta = lambda0 * viscl0 * Ra /
                         (cs_math_sq(ro0) * cp0 * g * pow(L,3) *
                          (T_hot - T_cold));

  /* Compute density in all cells */
  cs_real_t min_rho = 1.e15, max_rho = 0.;
  for (cs_lnum_t cell_id = 0; cell_id < n_cells; cell_id++) {
    const cs_real_t temp_cell = cvar_temp[cell_id];
    cpro_rho[cell_id] = ro0 * (1. - beta * (temp_cell - T_cold));
    min_rho = fmin(cpro_rho[cell_id], min_rho);
    max_rho = fmax(cpro_rho[cell_id], max_rho);
  }

  if (cs_glob_rank_id >= 0) {
    cs_parall_min(1, CS_REAL_TYPE, &min_rho);
    cs_parall_max(1, CS_REAL_TYPE, &max_rho);
  }

  bft_printf("min_rho %f max_rho %f\n", min_rho, max_rho);
}

You should now be able to launch the calculation and get results

Results: