Problem 6. A boundary layer is developing for uniform flow of air at STP over a flat plate as shown. The free- stream flow outside the boundary layer has an undisturbed velocity of U = 50 m/s. The plate has a width of b = 3.0 m perpendicular to the schematic. A control volume (CV) with control surfaces (ab), (bc), (cd), and (ad) is defined as shown. Assume that the flow in the boundary layer is turbulent at surface (cd) with a 1/7th power-law velocity profile and a boundary layer disturbance thickness of = 2.0 cm. For surfaces (ab), (bc), and (cd), calculate (a) mass flowrate and (b) momentum transported (in Newtons). (c) Determine the drag for the flat plate at surface (ad). y U control volume boundary-layer region a flat plate d U δ u(y)

Problem 6. A boundary layer is developing for uniform flow of air at STP over a flat plate as shown. The free- stream flow outside the boundary layer has an undisturbed velocity of U = 50 m/s. The plate has a width of b = 3.0 m perpendicular to the schematic. A control volume (CV) with control surfaces (ab), (bc), (cd), and (ad) is defined as shown. Assume that the flow in the boundary layer is turbulent at surface (cd) with a 1/7th power-law velocity profile and a boundary layer disturbance thickness of = 2.0 cm. For surfaces (ab), (bc), and (cd), calculate (a) mass flowrate and (b) momentum transported (in Newtons). (c) Determine the drag for the flat plate at surface (ad). y U control volume boundary-layer region a flat plate d U δ u(y)

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 5.24P: Engine oil at 100C flows over and parallel to a flat surface at a velocity of 3 m/s. Calculate the...

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Problem 6. A boundary layer is developing for uniform flow of air at STP over a flat plate as shown. The free-stream flow outside the boundary layer has an undisturbed velocity of U = 50 m/s. The plate has a width of b = 3.0 m perpendicular to the schematic. A control volume (CV) with control surfaces (ab), (bc), (cd), and (ad) is defined as shown. Assume that the flow in the boundary layer is turbulent at surface (cd) with a 1/7th power-law velocity profile and a boundary layer disturbance thickness of 8 = 2.0 cm. For surfaces (ab), (bc), and (cd), calculate (a) mass flowrate and (b) momentum transported (in Newtons). (c) Determine the drag for the flat plate at surface (ad). U U control volume u(y) boundary-layer region flat plate a
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