Heat conduction describes the form of heat transfer in which heat transport takes place in a solid or a stationary fluid as a result of a temperature difference without additional mass transport. In liquids and gases, the transport of heat energy is usually dominated by the accompanying convection, the heat conduction then plays a subordinate role.
The capability of a material to conduct heat is described by its thermal conductivity. The thermal conductivity corresponds to the amount of heat that flows through a cube that has a uniform temperature difference on two opposite surfaces. The thermal conductivity usually shows only a small variation over a wide temperature range. Phase transitions, on the other hand, often result in major, sudden changes.
Computation time / model size
In most technical applications there is no change of aggregate state. Therefore, from a numerical point of view, the solution of pure heat conduction problems is very easy. The requirements or restrictions on the model size depend on the type of examination, stationary or transient, or are determined by other load and boundary conditions.
Situations in which only heat conduction to describe a temperature field calculation occurs are rather rare. Overall, however, thermal conductivity in thermal simulations plays the same role as elasticity in structural mechanics. Without them there is no relation between the temperatures on one side and the heat flows on the other. As a result, heat conduction is an integral part of any thermal simulation.