Diffusivity is a rate of diffusion, a measure of the rate at which particles or heat or fluids can spread.

It is measured differently for different mediums.

Diffusivity may refer to:

  • Thermal diffusivity, diffusivity of heat
  • Diffusivity of mass:
  • Mass diffusivity, molecular diffusivity (often called "diffusion coefficient")
  • Eddy diffusion, eddy diffusivity
  • Kinematic viscosity, characterising momentum diffusivity
  • Magnetic diffusivity

Dimensions and units

Diffusivity has dimensions of length<sup>2</sup> / time, or m<sup>2</sup>/s in SI units and cm<sup>2</sup>/s in CGS units.

See also

  • Diffusibility

References