# Heat transfer

(Difference between revisions)
 Revision as of 10:59, 1 December 2005 (view source) (→Conduction)← Older edit Revision as of 11:04, 1 December 2005 (view source)Newer edit → Line 8: Line 8: [/itex] [/itex] Where Where + + Q = Heat conducted (W) k = Thermal conductivity of the material (W/m-K) k = Thermal conductivity of the material (W/m-K) - A = Cross-sectional area of the object parallel to heat conduction + A = Cross-sectional area of the object parallel to heat conduction (m2) T = Temparature (K) T = Temparature (K) - X = Length of the object + X = Length of the object (m) == Convection == == Convection ==

## Revision as of 11:04, 1 December 2005

```                     == Conduction ==
```
• Conduction can be defined as the heat transfer through a substance because of a temperature gradient. The rate of heat transfer by conduction between two regions of a substance is proportional to the temperature difference between them. The constant of propotionality is called thermal conductivity of the material.
• Mathematically, it can be described by using the Fourier's law:
$Q_{Conduction} = -k*A*dT/dX$

Where

```     Q = Heat conducted (W)
```
```     k = Thermal conductivity of the material (W/m-K)
```
```     A = Cross-sectional area of the object parallel to heat conduction (m2)
```
```     T = Temparature (K)
```
```     X = Length of the object (m)
```