1. Air at a temperature of 300 K flows over one side of a flat plate of width 1 m at a velocity of 20 m/s. The plate has a constant surface temperature of 350 K. Assume Rex, =5×10³. a) What is the velocity boundary layer thickness at the end of the plate if L = 0.25 m? What if L = 1 m? b) Calculate the drag on the plate if L = 0.25 m. What is the drag if L = 1 m? c) Find the heat transfer rate from the plate to the air if L = 0.25 m. What is the heat transfer rate if L = 1 m. d) A small diameter wire is placed at the leading edge of the flat plate. This wire trips the flow, causing it to be turbulent over the entire length of the plate. Repeat the calculations performed in a), b) and c) for this condition.

1. Air at a temperature of 300 K flows over one side of a flat plate of width 1 m at a velocity of 20 m/s. The plate has a constant surface temperature of 350 K. Assume Rex, =5×10³. a) What is the velocity boundary layer thickness at the end of the plate if L = 0.25 m? What if L = 1 m? b) Calculate the drag on the plate if L = 0.25 m. What is the drag if L = 1 m? c) Find the heat transfer rate from the plate to the air if L = 0.25 m. What is the heat transfer rate if L = 1 m. d) A small diameter wire is placed at the leading edge of the flat plate. This wire trips the flow, causing it to be turbulent over the entire length of the plate. Repeat the calculations performed in a), b) and c) for this condition.

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 5.26P

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