Reconsider Prob. 4–68. Using EES (or other) software, investigate the effect of the final center temperature of the egg on the time it will take for the center to reach this temperature. Let the temperature vary from 50°C to 95°C. Plot the time versus the temperature, and discuss the results.

Data from problem 68

An ordinary egg can be approximated as a 5.5-cmdiameter sphere whose properties are roughly k = 0.6 W/m · K and α = 0.14 × 10^-6 m²/s. The egg is initially at a uniform temperature of 8°C and is dropped into boiling water at 97°C. Taking the convection heat transfer coefficient to be h = 1400 W/m² · K, determine how long it will take for the center of the egg to reach 70°C. Solve this problem using analytical one-term approximation method (not the Heisler charts).

Transcribed Image Text:

Boiling water Egg T₁ = 8°C 97°C