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 × 10-5 m²/s, Cp=1008 J/kg-K, and Pr = 0.7154. 2m Air 1.25 m/s T₁ = 100°C D=4 cm 2m O, = 200 W Determine the air temperature at the 2 m length. The air temperature at the 2 m length is °C.

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 × 10-5 m²/s, Cp=1008 J/kg-K, and Pr = 0.7154. 2m Air 1.25 m/s T₁ = 100°C D=4 cm 2m O, = 200 W Determine the air temperature at the 2 m length. The air temperature at the 2 m length is °C.

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 7.27P

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