Astrophysics (index)


(the spreading of particles toward an even distribution)

Diffusion is the net movement of particles such as atoms or molecules from areas of higher concentration to areas of lower concentration.

A Diffusion Equation is an equation describing diffusion over time. Fick's Laws include a diffusion equation describing what happens in many cases. That type of diffusion is called Fickian Diffusion, and the equation is:

J = -D ——
  • J - the Diffusive Flux, the flow of the diffusing substance as substance/time.
  • D - the diffusion coefficient of the substance.
  • C - the concentration of the substance.
  • x - measurement over a direction over which we are describing the diffusion.