Air flows in a pipe under fully developed conditions with an average velocity of 1.25 m/s and a temperature of 24°C. The pipe's inner diameter is 4 cm, and its length is 4 m. The first half of the pipe is kept at a constant wall temperature of 100°C. The second half of the pipe is subjected to a constant heat flux of 200 W. The properties of air at 80°C are p = 0.9994 kg/m³, k = 0.02953 W/m-K, v= 2.097 x 10-5 m²/s, cp=1008 J/kg-K, and Pr = 0.7154. NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

Air flows in a pipe under fully developed conditions with an average velocity of 1.25 m/s and a temperature of 24°C. The pipe's inner diameter is 4 cm, and its length is 4 m. The first half of the pipe is kept at a constant wall temperature of 100°C. The second half of the pipe is subjected to a constant heat flux of 200 W. The properties of air at 80°C are p = 0.9994 kg/m³, k = 0.02953 W/m-K, v= 2.097 x 10-5 m²/s, cp=1008 J/kg-K, and Pr = 0.7154. NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.

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 7.31P

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