Example of .nts input file

# Free convection Ra=5 10^6 test case

# Include physical properties from standard library
include std "physical_properties.nts";

domain {
    spatial_dimension 2;
    corner_1_coordinates (0.0, 0.0);
    corner_2_coordinates (0.1, 0.1);
}

grid {
    grid_type regular;
    number_of_cells (32, 32);
    number_of_ghost_cells 1;
}

modeling {
    materials {
        fluid "air";
    }

    equations {
        navier_stokes {
            gravity_term (0.0, -9.81);

            boundary_condition {
                left wall;
                right wall;
                top wall;
                bottom wall;
            }
        }

        energy {
            boundary_condition {
                left dirichlet 300.53220725;
                right dirichlet 299.46779275;
                top neumann 0.0;
                bottom neumann 0.0;
            }
        }
    }
}

numerical_parameters {
    time_iterations 3000;

    stop_tests {
        stationarity_temperature 1.0e-11;
        stationarity_velocity 1.0e-11;
    }

    time_step fixed 0.5;

    navier_stokes {
        velocity_pressure timmermans;
        advection_scheme implicit o2_centered;

        solver_momentum hypre_gmres {
            max_iteration 200;
            tolerance 1.0e-15;
            initial_preconditioner left_jacobi;
       }
        solver_pressure hypre_bicgstab {
            max_iteration 100;
            tolerance 1.0e-14;
            initial_preconditioner left_jacobi;
            preconditioner pfmg {
                max_iteration 1;
                tolerance 0.0;
            }
        }
    }
    energy {
        advection_scheme implicit o2_centered;
        solver mumps_metis;
    }
}

post_processing {
    output_library adios;
    output_frequency 50;
    output_fields velocity, pressure, divergence, viscosity, temperature, conductivity, density;

    diagnostic_quantities nusselt_number;
    diagnostic_quantities mean velocity;

    validation {
        tolerance 1.0e-10;
        mean temperature 3.0000000000001228e+02;
        mean velocity 3.7921755054294410e-03;
    }
}