Thermal diffusivity
|
|
In heat transfer analysis, thermal diffusivity (symbol: <math>\alpha<math>) is the ratio of thermal conductivity to heat capacity.
- <math>\alpha = {k \over {\rho c_p}}<math>
where
k is thermal conductivity, measured in watts per metre-kelvin
ρcp is the volumetric heat capacity, measured in joules per cubic metre-kelvin
The SI units are square metres per second or m²/s.
Substances with high thermal diffusivity rapidly adjust their temperature to that of their surroundings, because they conduct heat quickly in comparison to their thermal 'bulk'.de:Temperaturleitfähigkeit