When a fluid flows over a surface, the shear stress 1 (N/m) at the surface is given by the expression du dy surface where u is the viscosity (N-s/m), u is the velocity parallel to the surface (m/s), and y is the distance normal to the surface (cm). Measurements of the velocity of an air stream flowing above a surface are made with an LDV (laser-Doppler-Velocimeter). The values given below were obtained. u y и 0.0 0.00 2.0 88.89 1.0 55.56 3.0 100.00 At the local temperature, p = 0.00024 N-s/m. In four decimal places, calculate du/dy at the surface using all the points. Answer =

When a fluid flows over a surface, the shear stress 1 (N/m) at the surface is given by the expression du dy surface where u is the viscosity (N-s/m), u is the velocity parallel to the surface (m/s), and y is the distance normal to the surface (cm). Measurements of the velocity of an air stream flowing above a surface are made with an LDV (laser-Doppler-Velocimeter). The values given below were obtained. u y и 0.0 0.00 2.0 88.89 1.0 55.56 3.0 100.00 At the local temperature, p = 0.00024 N-s/m. In four decimal places, calculate du/dy at the surface using all the points. Answer =

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 5.13P: 5.13 The torque due to the frictional resistance of the oil film between a rotating shaft and its...

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When a fluid flows over a surface, the shear stresS I (N/m) at the surface is given by the expression du dy surface where u is the viscosity (N-s/m), u is the velocity parallel to the surface (m/s), and y is the distance normal to the surface (cm). Measurements of the velocity of an air stream flowing above a surface are made with an LDV (laser-Doppler-Velocimeter). The values given below were obtained. y u y и 0.0 0.00 2.0 88.89 1.0 55.56 3.0 100.00 At the local temperature, u = 0.00024 N-s/m. In four decimal places, calculate du/dy at the surface using all the points.
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