Chapter 4 Transient Heat Conduction4-73A short cylinder is allowed to cool in atmospheric air. The temperatures at the centers of the cylinder and the top surface as well as the total heat transfer from the cylinder for 15 min of cooling are to be determined. Assumptions1Heat conduction in the short cylinder is two-dimensional, and thus the temperature varies in both the axial x- and the radial r- directions. 2The thermal properties of the cylinder are constant. 3The heat transfer coefficient is constant and uniform over the entire surface. 4 The Fourier number is τ> 0.2 so that the one-term approximate solutions (or the transient temperature charts) are applicable (this assumption will be verified). PropertiesThe thermal properties of brass are given to be ,ρ=8530 kg / m3CkJ/kg389.0°⋅=pC, , and CW/m110°⋅=kα=×−339 105.m /s2. Analysis This short cylinder can physically be formed by the intersection of a long cylinder of radius D/2 = 4 cm and a plane wall of thickness 2L= 15 cm. We measure xfrom the midplane.
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This note was uploaded on 01/19/2012 for the course PHY 4803 taught by Professor Dr.danielarenas during the Fall '10 term at UNF.