Consider two cases involving parallel flow of dry air at V=V= 2.5 m/s, T∞=45°C, and atmospheric pressure over an isothermal plate at Ts=20°C. In the first case, Rex,c=R⁢ex,c=5 × 105, while in the second case the flow is tripped to a turbulent state at x=0 m. a. At what x‐location, in m, are the thermal boundary layer thicknesses of the two cases equal? in m b. what is the q'' lam at W / m^2 c. what is the q'' turb at W / m^2

Consider two cases involving parallel flow of dry air at V=V= 2.5 m/s, T∞=45°C, and atmospheric pressure over an isothermal plate at Ts=20°C. In the first case, Rex,c=R⁢ex,c=5 × 105, while in the second case the flow is tripped to a turbulent state at x=0 m. a. At what x‐location, in m, are the thermal boundary layer thicknesses of the two cases equal? in m b. what is the q'' lam at W / m^2 c. what is the q'' turb at W / m^2

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 5.29P: Air at 20C flows at 1 m/s between two parallel flat plates spaced 5 cm apart. Estimate the distance...

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Air at 20C flows at 1 m/s between two parallel flat plates spaced 5 cm apart. Estimate the distance from the entrance to the point at which the hydrodynamic boundary layers meet.
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