Problem 1. The extent of the laminar boundary-layer region before transition to turbulent flow on the surface of an aircraft wing varies with altitude. (a) Calculate the critical length for laminar boundary-layer transition, LSL, at sea level moving at a velocity of 100 mph. (b) Plot the ratio of the critical length, Ler, at altitude to LSL as a function of altitude up to an altitude of z = 30 km. When evaluating properties, use the conditions defined by the U.S. Standard Atmosphere and the Sutherland correlation for viscosity from Appendix A of your textbook (or an online database). (c) Briefly discuss how the laminar boundary-layer length changes with altitude for a given speed and why.

Problem 1. The extent of the laminar boundary-layer region before transition to turbulent flow on the surface of an aircraft wing varies with altitude. (a) Calculate the critical length for laminar boundary-layer transition, LSL, at sea level moving at a velocity of 100 mph. (b) Plot the ratio of the critical length, Ler, at altitude to LSL as a function of altitude up to an altitude of z = 30 km. When evaluating properties, use the conditions defined by the U.S. Standard Atmosphere and the Sutherland correlation for viscosity from Appendix A of your textbook (or an online database). (c) Briefly discuss how the laminar boundary-layer length changes with altitude for a given speed and why.

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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