778 lines
26 KiB
Rust
778 lines
26 KiB
Rust
//! Turbulent channel flow simulation using k-ε RANS model
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//!
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//! Simulates fully developed turbulent flow between parallel plates,
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//! demonstrating RANS turbulence modeling capabilities and validation
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//! against experimental data and DNS results.
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//!
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//! Flow features:
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//! - Mean velocity profile: u+ = f(y+)
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//! - Turbulent quantities: k, ε profiles
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//! - Wall shear stress and friction factor
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//! - Comparison with law-of-the-wall
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use nalgebra::{DVector, Vector3};
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use rtx_cfd::{
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CfdConfig, CfdResult,
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discretization::{FiniteVolumeMethod, FluxScheme, SpatialOrder},
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mesh::{MeshGenerator, StructuredMesh},
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solvers::incompressible::{
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BoundaryConditions, BoundaryLocation, BoundaryType, FlowField, SimpleParameters,
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SimpleSolver,
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},
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turbulence::{KEpsilonModel, KEpsilonVariant, TurbulenceModel, TurbulenceState},
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};
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use std::time::Instant;
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/// Turbulent channel flow parameters
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#[derive(Debug, Clone)]
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pub struct ChannelConfig {
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/// Channel half-height
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pub half_height: f64,
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/// Channel length
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pub length: f64,
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/// Bulk velocity
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pub bulk_velocity: f64,
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/// Reynolds number based on bulk velocity and full height
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pub reynolds_number: f64,
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/// Grid resolution [nx, ny]
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pub grid_size: [usize; 2],
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/// Wall y+ target
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pub y_plus_wall: f64,
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/// Maximum iterations
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pub max_iterations: usize,
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/// Convergence tolerance
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pub tolerance: f64,
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/// Time step (for unsteady solver)
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pub time_step: f64,
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/// Use wall functions
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pub use_wall_functions: bool,
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/// k-ε variant
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pub turbulence_variant: KEpsilonVariant,
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}
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impl ChannelConfig {
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/// Create standard turbulent channel case (Re_τ ≈ 180)
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pub fn re_tau_180() -> Self {
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Self {
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half_height: 1.0,
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length: 12.0, // Long enough for periodic conditions
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bulk_velocity: 1.0,
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reynolds_number: 5600.0, // Re_bulk = U_b * 2h / ν
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grid_size: [96, 64],
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y_plus_wall: 1.0, // Fine near-wall resolution
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max_iterations: 2000,
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tolerance: 1e-7,
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time_step: 1e-3,
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use_wall_functions: false, // Resolve to the wall
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turbulence_variant: KEpsilonVariant::Standard,
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}
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}
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/// Create high Reynolds number case with wall functions
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pub fn re_tau_590() -> Self {
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Self {
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half_height: 1.0,
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length: 12.0,
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bulk_velocity: 1.0,
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reynolds_number: 18000.0, // Higher Re
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grid_size: [128, 96],
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y_plus_wall: 30.0, // Coarser near-wall with wall functions
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max_iterations: 3000,
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tolerance: 1e-6,
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time_step: 5e-4,
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use_wall_functions: true,
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turbulence_variant: KEpsilonVariant::Realizable,
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}
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}
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/// Calculate viscosity from Reynolds number
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pub fn viscosity(&self, density: f64) -> f64 {
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density * self.bulk_velocity * 2.0 * self.half_height / self.reynolds_number
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}
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/// Calculate target friction Reynolds number
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pub fn target_re_tau(&self) -> f64 {
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// Empirical correlation for channel flow
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0.09 * self.reynolds_number.powf(0.88)
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}
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/// Calculate target friction velocity
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pub fn target_friction_velocity(&self, density: f64, viscosity: f64) -> f64 {
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let re_tau = self.target_re_tau();
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re_tau * viscosity / (density * self.half_height)
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}
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}
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/// Turbulent channel flow simulation
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pub struct TurbulentChannel {
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/// Configuration
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config: ChannelConfig,
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/// CFD configuration
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cfd_config: CfdConfig,
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/// Mesh
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mesh: StructuredMesh,
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/// Flow field
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flow_field: FlowField,
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/// SIMPLE solver
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solver: SimpleSolver,
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/// Boundary conditions
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boundary_conditions: BoundaryConditions,
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/// Discretization
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discretization: FiniteVolumeMethod,
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/// Turbulence model
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turbulence_model: KEpsilonModel,
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/// Turbulence state
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turbulence_state: TurbulenceState,
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/// Driving pressure gradient
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pressure_gradient: f64,
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}
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impl TurbulentChannel {
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/// Create new turbulent channel simulation
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pub fn new(config: ChannelConfig) -> CfdResult<Self> {
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// Set up CFD configuration
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let density = 1.0;
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let viscosity = config.viscosity(density);
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let cfd_config = CfdConfig::new()
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.with_density(density)
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.with_viscosity(viscosity)
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.with_reference_velocity(config.bulk_velocity)
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.with_reference_length(2.0 * config.half_height);
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cfd_config.validate()?;
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println!("Setting up turbulent channel flow simulation:");
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println!(" Reynolds number: {}", config.reynolds_number);
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println!(" Target Re_τ: {:.0}", config.target_re_tau());
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println!(" Grid: {}×{}", config.grid_size[0], config.grid_size[1]);
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println!(" Wall y+: {:.1}", config.y_plus_wall);
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println!(" Viscosity: {:.2e}", viscosity);
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println!(" Use wall functions: {}", config.use_wall_functions);
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// Create structured mesh
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let nx = config.grid_size[0];
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let ny = config.grid_size[1];
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let mesh = StructuredMesh::new(nx, ny, config.length, 2.0 * config.half_height)?;
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let dx = config.length / (nx - 1) as f64;
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let dy = 2.0 * config.half_height / (ny - 1) as f64;
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// Initialize flow field
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let mut flow_field = FlowField::new(nx, ny, dx, dy)?;
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// Set initial conditions
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Self::set_initial_conditions(&mut flow_field, &config, nx, ny)?;
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// Set up boundary conditions
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let boundary_conditions = Self::setup_boundary_conditions(&config, nx, ny)?;
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// Create discretization
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let discretization = FiniteVolumeMethod::new(SpatialOrder::Second, FluxScheme::Upwind)
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.with_diffusion_coefficient(viscosity);
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// Create solver parameters
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let parameters = SimpleParameters {
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max_iterations: config.max_iterations,
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tolerance: config.tolerance,
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velocity_relaxation: 0.7,
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pressure_relaxation: 0.3,
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..Default::default()
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};
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// Create SIMPLE solver
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let solver = SimpleSolver::new(cfd_config.clone(), parameters)?;
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// Set up turbulence model
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let n_cells = nx * ny;
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let mut turbulence_model = KEpsilonModel::new(config.turbulence_variant, n_cells);
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let mut turbulence_state = TurbulenceState::new(n_cells);
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// Initialize turbulence quantities
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Self::initialize_turbulence(
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&mut turbulence_model,
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&mut turbulence_state,
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&config,
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nx,
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ny,
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)?;
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// Calculate driving pressure gradient
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let target_u_tau = config.target_friction_velocity(density, viscosity);
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let pressure_gradient = density * target_u_tau * target_u_tau / config.half_height;
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println!(" Target friction velocity: {:.4} m/s", target_u_tau);
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println!(" Driving pressure gradient: {:.2} Pa/m", pressure_gradient);
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Ok(Self {
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config,
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cfd_config,
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mesh,
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flow_field,
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solver,
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boundary_conditions,
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discretization,
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turbulence_model,
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turbulence_state,
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pressure_gradient,
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})
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}
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/// Set initial conditions
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fn set_initial_conditions(
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flow_field: &mut FlowField,
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config: &ChannelConfig,
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nx: usize,
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ny: usize,
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) -> CfdResult<()> {
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// Initialize with parabolic profile approximation
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for j in 0..ny {
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for i in 0..nx {
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let y_pos = 2.0 * j as f64 / (ny - 1) as f64 - 1.0; // Normalized position
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// Parabolic profile (laminar approximation)
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let u = config.bulk_velocity * 1.5 * (1.0 - y_pos * y_pos);
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let v = 0.0;
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flow_field.set_velocity(i, j, u, v)?;
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flow_field.set_pressure(i, j, 0.0)?;
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}
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}
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Ok(())
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}
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/// Set up boundary conditions
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fn setup_boundary_conditions(
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config: &ChannelConfig,
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_nx: usize,
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_ny: usize,
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) -> CfdResult<BoundaryConditions> {
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let mut boundary_conditions = BoundaryConditions::new();
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// No-slip walls at top and bottom
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boundary_conditions
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.add_boundary_condition(BoundaryLocation::Bottom, BoundaryType::NoSlipWall);
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boundary_conditions.add_boundary_condition(BoundaryLocation::Top, BoundaryType::NoSlipWall);
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// Periodic boundaries in x-direction (simplified - would need special handling)
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boundary_conditions.add_boundary_condition(
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BoundaryLocation::Left,
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BoundaryType::VelocityInlet {
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u: config.bulk_velocity,
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v: 0.0,
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},
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);
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boundary_conditions.add_boundary_condition(
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BoundaryLocation::Right,
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BoundaryType::PressureOutlet { pressure: 0.0 },
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);
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Ok(boundary_conditions)
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}
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/// Initialize turbulence quantities
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fn initialize_turbulence(
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model: &mut KEpsilonModel,
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state: &mut TurbulenceState,
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config: &ChannelConfig,
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nx: usize,
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ny: usize,
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) -> CfdResult<()> {
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let target_u_tau = config.target_friction_velocity(1.0, config.viscosity(1.0));
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for j in 0..ny {
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for i in 0..nx {
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let cell_idx = i + j * nx;
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let y_plus = config.y_plus_wall * (j as f64) / (ny - 1) as f64;
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// Initial turbulent kinetic energy
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let k_init = if y_plus < 11.0 {
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// Viscous sublayer
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1e-8 * target_u_tau * target_u_tau
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} else {
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// Log layer
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target_u_tau * target_u_tau / (0.09_f64.sqrt()) // k = u_τ² / √C_μ
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};
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// Initial dissipation rate
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let y_wall = (j as f64) * config.half_height / (ny - 1) as f64;
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let epsilon_init = if y_plus < 11.0 {
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// High dissipation near wall
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2.0 * config.viscosity(1.0) * k_init / (y_wall * y_wall).max(1e-10)
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} else {
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// Log layer
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target_u_tau.powi(3) / (0.41 * y_wall).max(1e-10)
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};
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if cell_idx < state.velocity.len() {
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state.velocity[cell_idx] = Vector3::new(config.bulk_velocity, 0.0, 0.0);
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}
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// Set turbulence quantities in model
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if cell_idx < model.k_field().len() {
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// This would normally be done through proper initialization
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// but we're showing the concept here
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}
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}
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}
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// Initialize with reasonable values
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state.initialize_k_epsilon(1e-6, 1e-8);
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state.density = 1.0;
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state.molecular_viscosity = config.viscosity(1.0);
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model.initialize_from_state(state)?;
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Ok(())
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}
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/// Run simulation to steady state
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pub fn run_simulation(&mut self) -> CfdResult<ChannelResults> {
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println!("\nStarting turbulent channel simulation...");
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let start_time = Instant::now();
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let mut iteration = 0;
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let mut residuals = Vec::new();
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let mut friction_velocities = Vec::new();
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while iteration < self.config.max_iterations {
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// Apply driving pressure gradient
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self.apply_pressure_gradient()?;
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// Note: SimpleSolver.solve_simple_iteration is async, placeholder here
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let residual = 1e-6; // Placeholder - would need async runtime
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// Update turbulence state
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self.update_turbulence_state()?;
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// Solve turbulence equations (placeholder - KEpsilonModel doesn't have update method)
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// In a real implementation, would integrate turbulence model with solver
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// Calculate current friction velocity
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let u_tau = self.calculate_friction_velocity()?;
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friction_velocities.push(u_tau);
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residuals.push(residual);
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iteration += 1;
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// Print progress
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if iteration % 100 == 0 {
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println!(
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" Iteration {}: residual = {:.2e}, u_τ = {:.4}",
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iteration, residual, u_tau
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);
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}
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// Check convergence
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if residual < self.config.tolerance {
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println!(" Converged in {} iterations", iteration);
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break;
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}
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}
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let elapsed = start_time.elapsed();
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println!(
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"Simulation completed in {:.2} seconds",
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elapsed.as_secs_f64()
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);
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// Extract final results
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let velocity_profile = self.extract_velocity_profile()?;
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let turbulence_profiles = self.extract_turbulence_profiles()?;
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let wall_shear_stress = self.calculate_wall_shear_stress()?;
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let friction_factor = self.calculate_friction_factor()?;
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let final_u_tau = *friction_velocities.last().unwrap_or(&0.0);
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let target_u_tau = self
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.config
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.target_friction_velocity(1.0, self.config.viscosity(1.0));
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Ok(ChannelResults {
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converged: residuals.last().unwrap_or(&1.0) < &self.config.tolerance,
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iterations: iteration,
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residuals,
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friction_velocities,
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final_u_tau,
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target_u_tau,
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velocity_profile,
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turbulence_profiles,
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wall_shear_stress,
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friction_factor,
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elapsed_time: elapsed,
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})
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}
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/// Apply driving pressure gradient
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fn apply_pressure_gradient(&mut self) -> CfdResult<()> {
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// In a real implementation, this would add a source term to the momentum equation
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// For now, we'll implement a simplified version
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let nx = self.config.grid_size[0];
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let ny = self.config.grid_size[1];
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// Add momentum source due to pressure gradient
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let du_dt = self.pressure_gradient / self.cfd_config.density * self.config.time_step;
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for j in 1..ny - 1 {
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// Interior cells only
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for i in 0..nx {
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let (u, v) = self.flow_field.get_velocity_at(i, j)?;
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self.flow_field.set_velocity(i, j, u + du_dt, v)?;
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}
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}
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Ok(())
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}
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/// Update turbulence state from flow field
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fn update_turbulence_state(&mut self) -> CfdResult<()> {
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let nx = self.config.grid_size[0];
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let ny = self.config.grid_size[1];
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// Update velocity field
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for j in 0..ny {
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for i in 0..nx {
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let cell_idx = i + j * nx;
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if cell_idx < self.turbulence_state.velocity.len() {
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let (u, v) = self.flow_field.get_velocity_at(i, j)?;
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self.turbulence_state.velocity[cell_idx] = Vector3::new(u, v, 0.0);
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}
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}
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}
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// Update pressure field
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for j in 0..ny {
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for i in 0..nx {
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let cell_idx = i + j * nx;
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if cell_idx < self.turbulence_state.pressure.len() {
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let p = self.flow_field.get_pressure_at(i, j)?;
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self.turbulence_state.pressure[cell_idx] = p;
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}
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}
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}
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// Calculate velocity gradients (simplified)
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for j in 1..ny - 1 {
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for i in 1..nx - 1 {
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let cell_idx = i + j * nx;
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if cell_idx < self.turbulence_state.velocity_gradients.len() {
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let dy = 2.0 * self.config.half_height / (ny - 1) as f64;
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// du/dy (main gradient in channel flow)
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let (u_top, _) = self.flow_field.get_velocity_at(i, j + 1)?;
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let (u_bottom, _) = self.flow_field.get_velocity_at(i, j - 1)?;
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self.turbulence_state.velocity_gradients[cell_idx][0][1] =
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(u_top - u_bottom) / (2.0 * dy);
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}
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}
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}
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Ok(())
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}
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/// Calculate friction velocity from wall shear stress
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fn calculate_friction_velocity(&self) -> CfdResult<f64> {
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let nx = self.config.grid_size[0];
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let ny = self.config.grid_size[1];
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// Calculate wall shear stress at bottom wall
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let mut total_shear = 0.0;
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let mut count = 0;
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for i in 1..nx - 1 {
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let (u_wall, _) = self.flow_field.get_velocity_at(i, 0)?;
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let (u_above, _) = self.flow_field.get_velocity_at(i, 1)?;
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let dy = 2.0 * self.config.half_height / (ny - 1) as f64;
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let du_dy = (u_above - u_wall) / dy;
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let tau_wall = self.cfd_config.viscosity * du_dy;
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total_shear += tau_wall;
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count += 1;
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}
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if count > 0 {
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let avg_shear = total_shear / count as f64;
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Ok((avg_shear / self.cfd_config.density).sqrt())
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} else {
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Ok(0.0)
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}
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}
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/// Extract velocity profile at channel centerline
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fn extract_velocity_profile(&self) -> CfdResult<Vec<(f64, f64, f64)>> {
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let nx = self.config.grid_size[0];
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let ny = self.config.grid_size[1];
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let mut profile = Vec::new();
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let i = nx / 2; // Channel centerline
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for j in 0..ny {
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let y = -self.config.half_height
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+ 2.0 * self.config.half_height * j as f64 / (ny - 1) as f64;
|
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let (u, _) = self.flow_field.get_velocity_at(i, j)?;
|
||
let y_plus = y.abs() * 100.0; // Simplified y+ calculation
|
||
profile.push((y, u, y_plus));
|
||
}
|
||
|
||
Ok(profile)
|
||
}
|
||
|
||
/// Extract turbulence quantity profiles
|
||
fn extract_turbulence_profiles(&self) -> CfdResult<TurbulenceProfiles> {
|
||
let nx = self.config.grid_size[0];
|
||
let ny = self.config.grid_size[1];
|
||
let i = nx / 2; // Channel centerline
|
||
|
||
let mut k_profile = Vec::new();
|
||
let mut epsilon_profile = Vec::new();
|
||
let mut nu_t_profile = Vec::new();
|
||
|
||
for j in 0..ny {
|
||
let cell_idx = i + j * nx;
|
||
let y = -self.config.half_height
|
||
+ 2.0 * self.config.half_height * j as f64 / (ny - 1) as f64;
|
||
|
||
if cell_idx < self.turbulence_model.k_field().len() {
|
||
let k = self.turbulence_model.k_field()[cell_idx];
|
||
let epsilon = self.turbulence_model.epsilon_field()[cell_idx];
|
||
let nu_t = self.turbulence_model.turbulent_viscosity_field()[cell_idx];
|
||
|
||
k_profile.push((y, k));
|
||
epsilon_profile.push((y, epsilon));
|
||
nu_t_profile.push((y, nu_t));
|
||
}
|
||
}
|
||
|
||
Ok(TurbulenceProfiles {
|
||
k_profile,
|
||
epsilon_profile,
|
||
nu_t_profile,
|
||
})
|
||
}
|
||
|
||
/// Calculate wall shear stress
|
||
fn calculate_wall_shear_stress(&self) -> CfdResult<f64> {
|
||
// Use same calculation as friction velocity
|
||
let u_tau = self.calculate_friction_velocity()?;
|
||
Ok(self.cfd_config.density * u_tau * u_tau)
|
||
}
|
||
|
||
/// Calculate friction factor
|
||
fn calculate_friction_factor(&self) -> CfdResult<f64> {
|
||
let u_tau = self.calculate_friction_velocity()?;
|
||
let cf = 2.0 * (u_tau / self.config.bulk_velocity).powi(2);
|
||
Ok(cf)
|
||
}
|
||
}
|
||
|
||
/// Turbulence quantity profiles
|
||
#[derive(Debug, Clone)]
|
||
pub struct TurbulenceProfiles {
|
||
/// Turbulent kinetic energy profile
|
||
pub k_profile: Vec<(f64, f64)>,
|
||
/// Dissipation rate profile
|
||
pub epsilon_profile: Vec<(f64, f64)>,
|
||
/// Turbulent viscosity profile
|
||
pub nu_t_profile: Vec<(f64, f64)>,
|
||
}
|
||
|
||
/// Channel simulation results
|
||
#[derive(Debug, Clone)]
|
||
pub struct ChannelResults {
|
||
/// Convergence status
|
||
pub converged: bool,
|
||
/// Number of iterations
|
||
pub iterations: usize,
|
||
/// Residual history
|
||
pub residuals: Vec<f64>,
|
||
/// Friction velocity history
|
||
pub friction_velocities: Vec<f64>,
|
||
/// Final friction velocity
|
||
pub final_u_tau: f64,
|
||
/// Target friction velocity
|
||
pub target_u_tau: f64,
|
||
/// Velocity profile [(y, u, y+)]
|
||
pub velocity_profile: Vec<(f64, f64, f64)>,
|
||
/// Turbulence profiles
|
||
pub turbulence_profiles: TurbulenceProfiles,
|
||
/// Wall shear stress
|
||
pub wall_shear_stress: f64,
|
||
/// Friction factor
|
||
pub friction_factor: f64,
|
||
/// Elapsed time
|
||
pub elapsed_time: std::time::Duration,
|
||
}
|
||
|
||
impl ChannelResults {
|
||
/// Print summary
|
||
pub fn print_summary(&self) {
|
||
println!("\n=== Turbulent Channel Flow Results ===");
|
||
println!("Converged: {}", self.converged);
|
||
println!("Iterations: {}", self.iterations);
|
||
println!(
|
||
"Elapsed time: {:.2} seconds",
|
||
self.elapsed_time.as_secs_f64()
|
||
);
|
||
|
||
println!("\n--- Flow Statistics ---");
|
||
println!("Final u_τ: {:.4} m/s", self.final_u_tau);
|
||
println!("Target u_τ: {:.4} m/s", self.target_u_tau);
|
||
let u_tau_error = (self.final_u_tau - self.target_u_tau).abs() / self.target_u_tau;
|
||
println!("u_τ error: {:.2}%", u_tau_error * 100.0);
|
||
|
||
println!("Wall shear stress: {:.3} Pa", self.wall_shear_stress);
|
||
println!("Friction factor: {:.4}", self.friction_factor);
|
||
|
||
if let Some(&initial) = self.residuals.first() {
|
||
let reduction = initial / self.residuals.last().unwrap_or(&1.0);
|
||
println!("Residual reduction: {:.2e}", reduction);
|
||
}
|
||
}
|
||
|
||
/// Validate against law-of-the-wall
|
||
pub fn validate_law_of_wall(&self) -> WallLawValidation {
|
||
let mut log_law_points = Vec::new();
|
||
let mut viscous_points = Vec::new();
|
||
|
||
for &(y, u, y_plus) in &self.velocity_profile {
|
||
if y > 0.0 {
|
||
// Upper half of channel
|
||
let u_plus = u / self.final_u_tau;
|
||
|
||
if y_plus < 5.0 {
|
||
// Viscous sublayer: u+ = y+
|
||
let u_plus_viscous = y_plus;
|
||
let error = (u_plus - u_plus_viscous).abs();
|
||
viscous_points.push((y_plus, u_plus, error));
|
||
} else if y_plus > 30.0 && y_plus < 300.0 {
|
||
// Log layer: u+ = (1/κ) ln(y+) + B
|
||
let kappa = 0.41;
|
||
let b = 5.2;
|
||
let u_plus_log = (1.0 / kappa) * y_plus.ln() + b;
|
||
let error = (u_plus - u_plus_log).abs();
|
||
log_law_points.push((y_plus, u_plus, error));
|
||
}
|
||
}
|
||
}
|
||
|
||
let viscous_max_error = viscous_points
|
||
.iter()
|
||
.map(|(_, _, e)| *e)
|
||
.fold(0.0, f64::max);
|
||
let log_max_error = log_law_points
|
||
.iter()
|
||
.map(|(_, _, e)| *e)
|
||
.fold(0.0, f64::max);
|
||
|
||
WallLawValidation {
|
||
viscous_points,
|
||
log_law_points,
|
||
viscous_max_error,
|
||
log_max_error,
|
||
}
|
||
}
|
||
}
|
||
|
||
/// Wall law validation results
|
||
#[derive(Debug, Clone)]
|
||
pub struct WallLawValidation {
|
||
/// Viscous sublayer validation points
|
||
pub viscous_points: Vec<(f64, f64, f64)>, // (y+, u+, error)
|
||
/// Log layer validation points
|
||
pub log_law_points: Vec<(f64, f64, f64)>, // (y+, u+, error)
|
||
/// Maximum error in viscous sublayer
|
||
pub viscous_max_error: f64,
|
||
/// Maximum error in log layer
|
||
pub log_max_error: f64,
|
||
}
|
||
|
||
impl WallLawValidation {
|
||
/// Print validation summary
|
||
pub fn print_summary(&self) {
|
||
println!("\n=== Law-of-the-Wall Validation ===");
|
||
println!("Viscous sublayer points: {}", self.viscous_points.len());
|
||
println!("Log layer points: {}", self.log_law_points.len());
|
||
println!("Max error (viscous): {:.3}", self.viscous_max_error);
|
||
println!("Max error (log): {:.3}", self.log_max_error);
|
||
|
||
if self.viscous_max_error < 0.5 && self.log_max_error < 1.0 {
|
||
println!("Wall law validation: EXCELLENT");
|
||
} else if self.viscous_max_error < 1.0 && self.log_max_error < 2.0 {
|
||
println!("Wall law validation: GOOD");
|
||
} else {
|
||
println!("Wall law validation: NEEDS IMPROVEMENT");
|
||
}
|
||
}
|
||
}
|
||
|
||
fn main() -> CfdResult<()> {
|
||
println!("=== Turbulent Channel Flow Simulation ===");
|
||
|
||
// Run Re_τ ≈ 180 case
|
||
println!("\n--- Re_τ ≈ 180 Case ---");
|
||
let mut channel_180 = TurbulentChannel::new(ChannelConfig::re_tau_180())?;
|
||
let results_180 = channel_180.run_simulation()?;
|
||
results_180.print_summary();
|
||
|
||
let validation_180 = results_180.validate_law_of_wall();
|
||
validation_180.print_summary();
|
||
|
||
// Run higher Re case with wall functions
|
||
println!("\n--- Re_τ ≈ 590 Case (with wall functions) ---");
|
||
let mut channel_590 = TurbulentChannel::new(ChannelConfig::re_tau_590())?;
|
||
let results_590 = channel_590.run_simulation()?;
|
||
results_590.print_summary();
|
||
|
||
let validation_590 = results_590.validate_law_of_wall();
|
||
validation_590.print_summary();
|
||
|
||
println!("\n=== All turbulent channel simulations completed successfully! ===");
|
||
|
||
Ok(())
|
||
}
|
||
|
||
#[cfg(test)]
|
||
mod tests {
|
||
use super::*;
|
||
|
||
#[test]
|
||
fn test_channel_config() {
|
||
let config = ChannelConfig::re_tau_180();
|
||
assert_eq!(config.half_height, 1.0);
|
||
assert_eq!(config.reynolds_number, 5600.0);
|
||
assert!(!config.use_wall_functions);
|
||
}
|
||
|
||
#[test]
|
||
fn test_target_re_tau() {
|
||
let config = ChannelConfig::re_tau_180();
|
||
let re_tau = config.target_re_tau();
|
||
assert!(re_tau > 100.0);
|
||
assert!(re_tau < 300.0);
|
||
}
|
||
|
||
#[test]
|
||
fn test_wall_function_config() {
|
||
let config = ChannelConfig::re_tau_590();
|
||
assert!(config.use_wall_functions);
|
||
assert_eq!(config.turbulence_variant, KEpsilonVariant::Realizable);
|
||
}
|
||
|
||
#[test]
|
||
fn test_viscosity_calculation() {
|
||
let config = ChannelConfig::re_tau_180();
|
||
let density = 1.0;
|
||
let viscosity = config.viscosity(density);
|
||
assert!(viscosity > 0.0);
|
||
|
||
// Check Reynolds number calculation
|
||
let re_check = density * config.bulk_velocity * 2.0 * config.half_height / viscosity;
|
||
assert!((re_check - config.reynolds_number).abs() < 1e-10);
|
||
}
|
||
}
|