4. Steam flowing through a long, thin-walled pipe maintains the pipe wall at a uniform temperature of 500K. The pipe is covered with an insulation blanket comprised of two different materials, A and B. The interface between the two materials may be assumed to have an infinite contact resistance, and the entire outer surface is exposed to air for which To = 300K and h = 25 W/m².K. Ts,2(A) T₁,2(B) T1= 500 K A B ₁ = 50 mm -2 = 100 mm -KA = 2 W/m-K -KB = 0.25 W/m-K To h a) Sketch the thermal circuit of the system. Label (using the preceding symbols) all pertinent nodes and resistances. b) For the prescribed conditions, what is the total heat loss from the pipe? What are the outer surface temperatures T₁,2(4) and TS,2(B)?

4. Steam flowing through a long, thin-walled pipe maintains the pipe wall at a uniform temperature of 500K. The pipe is covered with an insulation blanket comprised of two different materials, A and B. The interface between the two materials may be assumed to have an infinite contact resistance, and the entire outer surface is exposed to air for which To = 300K and h = 25 W/m².K. Ts,2(A) T₁,2(B) T1= 500 K A B ₁ = 50 mm -2 = 100 mm -KA = 2 W/m-K -KB = 0.25 W/m-K To h a) Sketch the thermal circuit of the system. Label (using the preceding symbols) all pertinent nodes and resistances. b) For the prescribed conditions, what is the total heat loss from the pipe? What are the outer surface temperatures T₁,2(4) and TS,2(B)?

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.12P

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