Problem 1: A rectangular (70mm Wide x 60mm Tall x 180mm long) air heater is used to heat 0.04m³ incoming air (Q = from 25°C to 60°C. To increase the surface area, the cross-section is split into 6 rectangular channels using aluminum fins, as shown below. The fins are evenly spaced and 2mm thick. What must the average surface temperature of the fins be to sufficiently heat the air?

Problem 1: A rectangular (70mm Wide x 60mm Tall x 180mm long) air heater is used to heat 0.04m³ incoming air (Q = from 25°C to 60°C. To increase the surface area, the cross-section is split into 6 rectangular channels using aluminum fins, as shown below. The fins are evenly spaced and 2mm thick. What must the average surface temperature of the fins be to sufficiently heat the air?

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.37P

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