A constant-property, one-dimensional plane slab of width 2L, initially at a uniform temperature, is heated convectively with
Question:
A constant-property, one-dimensional plane slab of width 2L, initially at a uniform temperature, is heated convectively with Bi = 1.
(a) At a dimensionless time of Fo1, heating is suddenly stopped, and the slab of material is quickly covered with insulation. Sketch the dimensionless surface and midplane temperatures of the slab as a function of dimensionless time over the range 0 < Fo < ∞. By changing the duration of heating to Fo2, the steady-state midplane temperature can be set equal to the midplane temperature at Fo1. Is the value of Fo2 equal to, greater than, or less than Fo1?
(b) Letting Fo2 Fo1 + ΔFo, derive an analytical expression for ΔFo, and evaluate ΔFo for the conditions of part (a).
(c) Evaluate ΔFo for Bi = 0.01, 0.1, 10, 100, and ∞ when Fo1 and Fo2 are both greater than 0.2.
Step by Step Answer:
For part a the dimensionless surface and midplane temperatures of the slab as a function of dimensio...View the full answer
Fundamentals Of Heat And Mass Transfer
ISBN: 9780470501979
7th Edition
Authors: Theodore L. Bergman, Adrienne S. Lavine, Frank P. Incropera, David P. DeWitt
