Consider a large plane wall of thickness 2L=20mm. Both surfaces of the wall are convectively cooled by the surrounding coolant at Too = 250°C with a heat transfer coefficient of h= 1100 W/m³.K. A fuel element of a nuclear reactor is considered in the shape of this large plane wall with given constant thermal properties as thermal conductivity k = 30 W/m.K and a = 5 x 10-6m²/s. It is known that heat is generated uniformly within the element at a volumetric rate of q = 1x 107W/m³. A departure from the steady-state conditions associated with normal operation will occur if there is a change in the generation rate. Consider a sudden change to d2 = 2 × 107W /m³. Assuming steady one-dimensional heat transfer along the wall, use the explicit finite- difference method to show how to calculate temperature To at 1.2 sec and temperature Ts at 1.5 sec. (show which equation to use and the calculations in details)

Consider a large plane wall of thickness 2L=20mm. Both surfaces of the wall are convectively cooled by the surrounding coolant at Too = 250°C with a heat transfer coefficient of h= 1100 W/m³.K. A fuel element of a nuclear reactor is considered in the shape of this large plane wall with given constant thermal properties as thermal conductivity k = 30 W/m.K and a = 5 x 10-6m²/s. It is known that heat is generated uniformly within the element at a volumetric rate of q = 1x 107W/m³. A departure from the steady-state conditions associated with normal operation will occur if there is a change in the generation rate. Consider a sudden change to d2 = 2 × 107W /m³. Assuming steady one-dimensional heat transfer along the wall, use the explicit finite- difference method to show how to calculate temperature To at 1.2 sec and temperature Ts at 1.5 sec. (show which equation to use and the calculations in details)

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 2.38P: 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from...

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