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 length2 / time, or m2/s in SI units and cm2/s in CGS units.

See also

• Diffusibility

References