Consider air flow over a flat plate of length, L = 1 m under conditions for which transition to turbulence occurs at xe = 0.5 m based on the critical Reynolds number of 5x10³. Also, in the laminar and turbulent regions, the local convection heat transfer coefficients are given by, respectively, hlam (x) = Clam x0.5 and hurb (x) = Cturb.X-0.2 where, at T = 300 K, Clam = 8.345 W/m¹.5K, Curb = 47.95 W/m¹8 K, and x has units of m. (a) Using the thermophysical properties of air at 300 K, determine the air velocity. (b) Develop an expression for the average convection coefficient, ham(x), as a function of distance from the leading edge, x, for the laminar region, 0 < x < xe. (c) Develop an expression for the average convection coefficient, hurb(x), as a function of distance from the leading edge, x, for the turbulent region, xe

Consider air flow over a flat plate of length, L = 1 m under conditions for which transition to turbulence occurs at xe = 0.5 m based on the critical Reynolds number of 5x10³. Also, in the laminar and turbulent regions, the local convection heat transfer coefficients are given by, respectively, hlam (x) = Clam x0.5 and hurb (x) = Cturb.X-0.2 where, at T = 300 K, Clam = 8.345 W/m¹.5K, Curb = 47.95 W/m¹8 K, and x has units of m. (a) Using the thermophysical properties of air at 300 K, determine the air velocity. (b) Develop an expression for the average convection coefficient, ham(x), as a function of distance from the leading edge, x, for the laminar region, 0 < x < xe. (c) Develop an expression for the average convection coefficient, hurb(x), as a function of distance from the leading edge, x, for the turbulent region, xe

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 7.13P

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