ABSTRACT
Thermal diffusivity indicates how fast heat propagates through a sample while heating or cooling. Thermal diffusivity is a lumped parameter used in the heat transfer calculation by conduction. The rate at which heat diffuses by conduction through a material depends on the thermal diffusivity and can be defined as
a ¼ k rCp
(20:1)
a is the thermal diffusivity (m2=s) r is the density (kg=m3) Cp is the specific heat (J=kg K) at constant pressure k is the thermal conductivity (W=mK)
20.2 MEASUREMENT TECHNIQUES
Thermal diffusivity can be determined either by direct experiment or estimated from the thermal conductivity, specific heat, and density data. The estimation of thermal diffusivity can be roughly divided into two groups: (a) direct measurement and (b) indirect prediction.
