Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity of 8.5 m/s and a temperature of 40 degrees Celsius. The flowing air has a thermal conductivity of 0.028 W/m K, kinematic viscosity of 16.95 x 10-6 m2/s and from empirical correlations, the Nusselt number has been approximated to be 425. Find out the convective heat flow coefficient (h). a. 54.71 W/m2 K b. 34.71 W/m2 K C. 44.71 W/m2 K d. 24.71 W/m2 K

Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity of 8.5 m/s and a temperature of 40 degrees Celsius. The flowing air has a thermal conductivity of 0.028 W/m K, kinematic viscosity of 16.95 x 10-6 m2/s and from empirical correlations, the Nusselt number has been approximated to be 425. Find out the convective heat flow coefficient (h). a. 54.71 W/m2 K b. 34.71 W/m2 K C. 44.71 W/m2 K d. 24.71 W/m2 K

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 7.20P

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