Heat Transfer Described by Fouriers Law

Fourier s law of heat conduction states that heat transfer by molecular interactions at any point in a solid or fluid is proportional in magnitude and coincident with the direction of the negative gradient of the temperature field [48]  

Fourier s law is the simplest form of a general energy flux and is strictly applicable only when the system is uniform in all respects except for the temperature gradient, that is, there are no mass concentration gradients or gradients in other intensive properties. 

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