Process by which heat is transferred within an object
For other uses, see Conduction (disambiguation).
Conduction is the process by which heat is transferred from the hotter end to the colder end of an object. The ability of the object to conduct heat is known as its thermal conductivity, and is denoted k.
Heat spontaneously flows along a temperature gradient (i.e. from a hotter body to a colder body). For example, heat is conducted from the hotplate of an electric stove to the bottom of a saucepan in contact with it. In the absence of an opposing external driving energy source, within a body or between bodies, temperature differences decay over time, and thermal equilibrium is approached, temperature becoming more uniform.
In conduction, the heat flow is within and through the body itself. In contrast, in heat transfer by thermal radiation, the transfer is often between bodies, which may be separated spatially. Heat can also be transferred by a combination of conduction and radiation. In solids, conduction is mediated by the combination of vibrations and collisions of molecules, propagation and collisions of phonons, and diffusion and collisions of free electrons. In gases and liquids, conduction is due to the collisions and diffusion of molecules during their random motion. Photons in this context do not collide with one another, and so heat transport by electromagnetic radiation is conceptually distinct from heat conduction by microscopic diffusion and collisions of material particles and phonons. But the distinction is often not easily observed unless the material is semi-transparent.
In the engineering sciences, heat transfer includes the processes of thermal radiation, convection, and sometimes mass transfer.[further explanation needed] Usually, more than one of these processes occurs in a given situation.
and 28 Related for: Thermal conduction information
differences decay over time, and thermal equilibrium is approached, temperature becoming more uniform. In conduction, the heat flow is within and through...
is the thermal conductivity, and ∇ T {\displaystyle \nabla T} is the temperature gradient. This is known as Fourier's Law for heat conduction. Although...
transfer is classified into various mechanisms, such as thermalconduction, thermal convection, thermal radiation, and transfer of energy by phase changes...
Thermal insulation provides a region of insulation in which thermalconduction is reduced, creating a thermal break or thermal barrier, or thermal radiation...
developed three generations of the ThermalConduction Module (TCM) which used a water-cooled cold plate in direct thermal contact with integrated circuit...
internal thermal equilibrium. Heat can flow into or out of a closed system by way of thermalconduction or of thermal radiation to or from a thermal reservoir...
convection and thermalconduction are taken into account in the U-value. Although it has the same units as heat transfer coefficient, thermal transmittance...
then the flow of electrons from valence to conduction band is possible only if an external energy (thermal, etc.) is supplied; these groups with small...
In heat transfer, thermal engineering, and thermodynamics, thermal conductance and thermal resistance are fundamental concepts that describe the ability...
very different from the photospheric radiative processes), or on thermalconduction. Furthermore, the presence of electric charges induces the generation...
Mixed conductor, ionic and electronic Electrical conduction system of the heart ThermalconductionThermal conductivity Bus conductor, checking tickets Conductor...
In physics, thermal contact conductance is the study of heat conduction between solid or liquid bodies in thermal contact. The thermal contact conductance...
vessels, rather than relying on indirect radiation, convection, or thermalconduction. Induction cooking allows high power and very rapid increases in temperature...
electrical efficiency but let more heat leak from the hot to cold side by thermalconduction. For large temperature differences, longer pillars are far less efficient...
infrared (IR) spectrum.: 73–86 Thermal radiation is one of the fundamental mechanisms of heat transfer, along with conduction and convection. The primary...
Scheele distinguished heat transfer by thermal radiation (radiant heat) from that by convection and conduction in 1777. In the 17th century, it came to...
of mitigating the effects of thermalconduction is to introduce insulation . The second consideration is the high thermal mass of concrete slabs, which...
to the colder system until they are in thermal equilibrium. Such heat transfer occurs by conduction or by thermal radiation. Experimental physicists, for...
Newtonian fluid subject to thermalconduction and viscous forces: ρ T D s D t ⏟ Heat Gain = ∇ ⋅ ( κ ∇ T ) ⏟ ThermalConduction + μ 2 ( ∂ v i ∂ x j + ∂ v...
The study of heat conduction between such bodies is called thermal contact conductance (or thermal contact resistance). Thermal equilibrium - When two...
and graduated with his PhD in 1914; his dissertation concerned "ThermalConduction and Radiation". This followed his 1913 co-authoring of a book on the...
materials to create thermal breaks. Heat transfer occurs through three mechanisms: convection, radiation, and conduction. A thermal bridge is an example...
ratio. It can be shown by using the Wiedemann–Franz law, that the thermalconduction is phonon-dominated. However, for a gated graphene strip, an applied...
activity, this heat flows through the crust by a slow process of thermalconduction, but in volcanic areas, the heat is carried to the surface more rapidly...
Unlike heat transmitted by thermalconduction or thermal convection, thermal radiation can propagate through a vacuum. Thermal radiation is characterized...
turbulence for instance) is the dominant mechanism compared to conduction. This table shows thermal conductivity in SI units of watts per metre-kelvin (W·m−1·K−1)...
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