Thermal effusivity

In Thermodynamics, the thermal effusivity of a material is defined as the square root of the product of the material's thermal conductivity and its volumetric heat capacity.

Here, k is the thermal conductivity, ${\displaystyle \rho }$ is the density and ${\displaystyle c_{p}}$ is the specific heat capacity. The product of ${\displaystyle \rho }$ and ${\displaystyle c_{p}}$ is known as the volumetric heat capacity.

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