A wall 0.12 m thick having a thermal diffusivity of 1.5x10-6 m²/s is initially at a uniform temperature of 85°C. Suddenly, one face is lowered to a temperature of 20°C while the other face is perfectly insulated. Using a numerical method with space and time increments of 30mm and 300 sec., respectively, determine the temperature distribution within the wall after 45min has elapsed. Also, obtain the temperature distribution after 45 minutes for the following conditions/cases (use the explicit method) 1. Ax=30mm At=300 sec. 2. Ax=30mm At=450 sec. 3. Ax=15mm At= find the largest At to obtain the solution. 4. Ax=7.5mm At=? sec. 5. Ax=30mm At=150 sec. 6. Ax=30mm At=75 sec. Plot temperature distribution for cases 1, 3, and 4 Compare T at the insulated side after 45 min for all cases and with the exact solution (tabulate results)

A wall 0.12 m thick having a thermal diffusivity of 1.5x10-6 m²/s is initially at a uniform temperature of 85°C. Suddenly, one face is lowered to a temperature of 20°C while the other face is perfectly insulated. Using a numerical method with space and time increments of 30mm and 300 sec., respectively, determine the temperature distribution within the wall after 45min has elapsed. Also, obtain the temperature distribution after 45 minutes for the following conditions/cases (use the explicit method) 1. Ax=30mm At=300 sec. 2. Ax=30mm At=450 sec. 3. Ax=15mm At= find the largest At to obtain the solution. 4. Ax=7.5mm At=? sec. 5. Ax=30mm At=150 sec. 6. Ax=30mm At=75 sec. Plot temperature distribution for cases 1, 3, and 4 Compare T at the insulated side after 45 min for all cases and with the exact solution (tabulate results)

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.24P

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