Chapter 4 Transient Heat Conduction4-77EA hot dog is dropped into boiling water. The center temperature of the hot dog is do be determined by treating hot dog as a finite cylinder and an infinitely long cylinder. Assumptions1When treating hot dog as a finite cylinder, heat conduction in the hot dog is two-dimensional, and thus the temperature varies in both the axial x- and the radial r- directions. When treating hot dog as an infinitely long cylinder, heat conduction is one-dimensional in the radial r- direction. 2The thermal properties of the hot dog 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 the hot dog are given to be k = 0.44 Btu/h.ft.°F, ρ= 61.2 lbm/ft3Cp= 0.93 Btu/lbm.°F, and α= 0.0077 ft2/h.
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