Air at 305 K flows at 4 m/s over a flat plate at 350 K. The air properties are as follows: density =1.1 kg/m3, viscosity =18.1×10−6 Pa.s, specific heat capacity =1005 J/kgK, and thermal conductivity =0.024 W/mK. The velocity and temperature profiles are assumed to be linear, giving the local Nusselt number to be Nux = 0.289 Rex1/ 2Pr1/3. The flow will become turbulent at a Reynolds number of 5×105. Assume the width of the plate perpendicular to the air flow is 1 m. At what distance from the leading edge does the flow become turbulent? ________m What is the heat transfer at the point of transition? ___________W What is the total heat transfer along the length of the plate where the flow is laminar? __________W

Air at 305 K flows at 4 m/s over a flat plate at 350 K. The air properties are as follows: density =1.1 kg/m3, viscosity =18.1×10−6 Pa.s, specific heat capacity =1005 J/kgK, and thermal conductivity =0.024 W/mK. The velocity and temperature profiles are assumed to be linear, giving the local Nusselt number to be Nux = 0.289 Rex1/ 2Pr1/3. The flow will become turbulent at a Reynolds number of 5×105. Assume the width of the plate perpendicular to the air flow is 1 m. At what distance from the leading edge does the flow become turbulent? __m What is the heat transfer at the point of transition? _W What is the total heat transfer along the length of the plate where the flow is laminar? ______W

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.15P

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Air at 305 K flows at 4 m/s over a flat plate at 350 K. The air properties are as follows: density =1.1 kg/m3, viscosity =18.1×10−6 Pa.s, specific heat capacity =1005 J/kgK, and thermal conductivity =0.024 W/mK. The velocity and temperature profiles are assumed to be linear, giving the local Nusselt number to be Nux = 0.289 Rex1/ 2Pr1/3. The flow will become turbulent at a Reynolds number of 5×105. Assume the width of the plate perpendicular to the air flow is 1 m. At what distance from the leading edge does the flow become turbulent? ________m What is the heat transfer at the point of transition? ___________W What is the total heat transfer along the length of the plate where the flow is laminar? __________W
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