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The heat flow can be modelled by analogy to an electrical circuit where heat flow is represented by current, temperatures are represented by voltages, heat sources are represented by constant current sources, absolute thermal resistances are represented by resistors and thermal capacitances by capacitors.
Assuming the element behaves as a perfect resistor and that the power is completely converted into heat, the formula can be re-written by substituting Ohm's law, =, into the generalized power equation: = = = / where R is the resistance.
The formula for Joule heating is: = where P is the power (energy per unit time) converted from electrical energy to thermal energy, R is the resistance, and I is the current through the resistor. Dependence on other conditions
The thermal conductivity of a material is a measure of its ability to conduct heat.It is commonly denoted by , , or and is measured in W·m −1 ·K −1.. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity.
Most experimentally determined values of the thermal contact resistance fall between 0.000005 and 0.0005 m 2 K/W (the corresponding range of thermal contact conductance is 200,000 to 2000 W/m 2 K). To know whether the thermal contact resistance is significant or not, magnitudes of the thermal resistances of the layers are compared with typical ...
This value is different at every interface and is an important concept in understanding heat flow at an interface. The series solution can be analyzed with a nomogram . A nomogram has a relative temperature as the y coordinate and the Fourier number, which is calculated by Fo = α t L 2 . {\displaystyle {\textit {Fo}}={\frac {\alpha t}{L^{2}}}.}
A heating element is a device used for conversion of electric energy into heat, consisting of a heating resistor and accessories. [1] Heat is generated by the passage of electric current through a resistor through a process known as Joule heating. Heating elements are used in household appliances, industrial equipment, and scientific ...
A fundamental solution, also called a heat kernel, is a solution of the heat equation corresponding to the initial condition of an initial point source of heat at a known position. These can be used to find a general solution of the heat equation over certain domains; see, for instance, ( Evans 2010 ) for an introductory treatment.