3- A large plane wall has a thickness L=50 cm and thermal conductivity k=25 W/m.K. On the left surface (x=0), it is subjected to a uniform heat flux go, while the surface temperature To is constant. On the right surface, it experiences convection and radiation heat transfer while the surface temperature is TL = 225°C and surrounding temperature is 25°C. The emissivity and the convection heat transfer coefficient on the right surface are 0.7 and 15 W/m²K, respectively. (a) Derive the temperature distribution equation for the wall parametrically (based on x, T₁, qo, L, and k). Plane wall Tsurr = 25°C T% = 25°C k = 25 W/m.K h = 15 W/m²K 90 ε = 0.7 T₁ = 225°C (b) Determine the temperature of the left surface of the wall at x=0? L x

3- A large plane wall has a thickness L=50 cm and thermal conductivity k=25 W/m.K. On the left surface (x=0), it is subjected to a uniform heat flux go, while the surface temperature To is constant. On the right surface, it experiences convection and radiation heat transfer while the surface temperature is TL = 225°C and surrounding temperature is 25°C. The emissivity and the convection heat transfer coefficient on the right surface are 0.7 and 15 W/m²K, respectively. (a) Derive the temperature distribution equation for the wall parametrically (based on x, T₁, qo, L, and k). Plane wall Tsurr = 25°C T% = 25°C k = 25 W/m.K h = 15 W/m²K 90 ε = 0.7 T₁ = 225°C (b) Determine the temperature of the left surface of the wall at x=0? L x

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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Show that the rate of heat conduction per unit length through a long, hollow cylinder of inner radius ri and outer radius ro, made of a material whose thermal conductivity varies linearly with temperature, is given by qkL=TiTo(rori)/kmA where Ti = temperature at the inner surface To = temperature at the outer surface A=2(rori)/ln(ro/ri)km=ko[1+k(Ti+To)/2]L=lenthofcyclinder
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A square silicon chip 7mm7mm in size and 0.5-mm thick is mounted on a plastic substrate as shown in the sketch below. The top surface of the chip is cooled by a synthetic liquid flowing over it. Electronic circuits on the bottom of the chip generate heat at a rate of 5 W that must be transferred through the chip. Estimate the steady-state temperature difference between the front and back surfaces of the chip. The thermal conductivity of silicon is 150 W/m K. Problem 1.6
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