Measuring the Thermal Diffusivity

The responsiveness of a substance to temperature changes is contingent on its thermal conductivity, density, and specific heat capacity. Thermal conductivity dictates the speed at which heat spreads in a material, while specific heat capacity quantifies the amount of heat stored in the material.

Density accounts for the amount of substance per cubic meter, and these interrelations are encapsulated by thermal diffusivity. This property is calculated as the ratio of thermal conductivity to the product of specific heat capacity and density, yielding a unit of measure in square meters per second [m²/s].

Thermal diffusivity is crucial for assessing heating and cooling processes, temperature variations in living spaces, and thermal stresses in components. It serves as a vital criterion in civil engineering classifications, particularly in preventing the spread of fire.

Materials with high thermal conductivity, such as metals and graphite, are advantageous for achieving rapid temperature compensation. These materials find applications in temperature measuring instruments and temperature controllers. Conversely, non-metals exhibit significantly lower temperature conduction, making them suitable for tasks like heat storage in regenerators.

The measurement of thermal diffusivity involves placing a material sample between two elements with constant but different temperatures. The local and temporal temperature profile within the sample is then evaluated, and this process can be realized, for instance, through a Heat Flow measurement.

Scroll to Top