CONDUCTION HEAT TRANSFER

CONDUCTION HEAT TRANSFER Heat Transfer CONDUCTION HEAT TRANSFER Conduction heat transfer is the transfer of thermal energy by interactions between adjacent atoms and molecules of a solid. EO 1.6 Given Fourier’s Law of Conduction, CALCULATE the conduction heat flux in a rectangular coordinate system. EO 1.7 Given the formula and the necessary values, CALCULATE the equivalent thermal resistance. EO 1.8 Given Fourier’s Law of Conduction, CALCULATE the conduction heat flux in a cylindrical coordinate system. Conduction Conduction involves the transfer of heat by the interaction between adjacent molecules of a material. Heat transfer by conduction is dependent upon the driving "force" of temperature difference and the resistance to heat transfer. The resistance to heat transfer is dependent upon the nature and dimensions of the heat transfer medium. All heat transfer problems involve the temperature difference, the geometry, and the physical properties of the object being studied. In conduction heat transfer problems, the object being studied is usually a solid. Convection problems involve a fluid medium. Radiation heat transfer problems involve either solid or fluid surfaces, separated by a gas, vapor, or vacuum. There are several ways to correlate the geometry, physical properties, and temperature difference of an object with the rate of heat transfer through the object. In conduction heat transfer, the most common means of correlation is through Fourier’s Law of Conduction. The law, in its equation form, is used most often in its rectangular or cylindrical form (pipes and cylinders), both of which are presented below. Rectangular (2-4) Q k A � � � � � � DT Dx Cylindrical (2-5) Q k A^� � � � � � DT Dr HT-02 Page 6 Rev. 0