A 1.5-m long, copper rod is removed from a heat- treatment oven at 550°C and immersed in a 55°C airstream flowing at 2.5 m/s along the direction shown in the figure. If the rod has a 10 cm x 10 cm square cross-section, determine the following values: (for air, use k = 0.02735 W/m.K, Pr 0.72, u = 1.963x10 5 Pa.s, us = 3.261x10S Pa.s, cp = 1007 J/kg.K, p = 1.092 kg/m3) Air a- Nusselt number, Nu = b- Convection heat transfer coefficient, h = W/m?.K c- Rate of heat loss from the rod, Q = kW

A 1.5-m long, copper rod is removed from a heat- treatment oven at 550°C and immersed in a 55°C airstream flowing at 2.5 m/s along the direction shown in the figure. If the rod has a 10 cm x 10 cm square cross-section, determine the following values: (for air, use k = 0.02735 W/m.K, Pr 0.72, u = 1.963x10 5 Pa.s, us = 3.261x10S Pa.s, cp = 1007 J/kg.K, p = 1.092 kg/m3) Air a- Nusselt number, Nu = b- Convection heat transfer coefficient, h = W/m?.K c- Rate of heat loss from the rod, Q = kW

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 7.38P

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