Lämpödiffuusioarvo

Lämpödiffuusioarvo, often referred to as thermal diffusivity, is a thermophysical property of a material that describes how quickly temperature diffuses through it. It quantifies the rate at which heat is conducted through a material relative to its capacity to store heat. A high thermal diffusivity means that heat can travel quickly through the material, while a low value indicates that heat travels slowly.

The mathematical definition of thermal diffusivity, symbolized by the Greek letter alpha (α), is the thermal conductivity (k) divided by the product of density (ρ) and specific heat capacity (c_p). Therefore, the formula is α = k / (ρ * c_p). This relationship highlights that a material with high thermal conductivity and low density and specific heat capacity will have a high thermal diffusivity.

Thermal diffusivity is an important parameter in various engineering and scientific applications. In heat transfer analysis, it helps predict how temperature distributions change over time. For instance, in the design of heat sinks or thermal insulation, understanding thermal diffusivity is crucial. Materials with high thermal diffusivity are used when rapid heat dissipation is desired, such as in electronic components. Conversely, materials with low thermal diffusivity are preferred for insulation purposes, as they resist the flow of heat, maintaining temperature differences. It is measured in units of square meters per second (m²/s) or square millimeters per second (mm²/s).