Thermal diffusivity

In heat transfer analysis, thermal diffusivity (symbol: lpha) is the ratio of thermal conductivity to heat capacity.

Related Topics:
Heat transfer - Thermal conductivity - Heat capacity

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:lpha = {k over { ho c_p}}

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where

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k is thermal conductivity, measured in watts per metre-kelvin

Related Topics:
Watt - Metre - Kelvin

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ρcp is the volumetric heat capacity, measured in joules per cubic metre-kelvin

Related Topics:
Volumetric heat capacity - Joule - Cubic metre - Kelvin

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The SI units are square metres per second or m²/s.

Related Topics:
SI - Square metre - Second

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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'.

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