diffusion.hpp File Reference

Explicit Euler diffusion steps for 2D uniform grids. More...

#include "pde/stencil.hpp"
#include "core/vector.hpp"
#include "core/policy.hpp"

Go to the source code of this file.

Namespaces
namespace	num
namespace	num::pde

Functions
void	num::pde::diffusion_step_2d (Vector &u, int N, double coeff, Backend b=best_backend)
void	num::pde::diffusion_step_2d_dirichlet (Vector &u, int N, double coeff, Backend b=best_backend)

Detailed Description

Explicit Euler diffusion steps for 2D uniform grids.

diffusion_step_2d – u += coeff * ∆_periodic(u), periodic BC diffusion_step_2d_dirichlet – u += coeff * ∆_dirichlet(u), Dirichlet BC

coeff = α·dt/h² where α is the diffusion coefficient.

Typical usage (viscosity in Navier-Stokes):

const double coeff = dt * nu / (h * h);
num::pde::diffusion_step_2d(u_star, N, coeff, num::best_backend);
num::pde::diffusion_step_2d(v_star, N, coeff, num::best_backend);

Definition in file diffusion.hpp.