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Measurements in Boundary Layer Flows

In: Science

Submitted By Madshem
Words 7310
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Abstract: In this experiment, the velocity profile for a flat plate at zero pressure gradient of a boundary layer at two different stream wise points were acquired. The investigation was also based on and how changes in Reynolds number affect the velocity distribution within boundary layers. Parameters such as the Momentum Thickness, Displacement Thickness, Shape Factor, shear stress and coefficient of friction was also calculated to gain a better understand of boundary layers. The experimental values calculated were compared to the theoretical Blasius for laminar flow and Power Law Solutions for turbulent flow to see how they varied. It was found out the higher the Reynolds number the greater the boundary layer thickness. As the boundary layer progressed the flow went from Laminar to Turbulent. Turbulent flow is more erratic and had a steeper velocity profile affect the shear stress. The momentum thickness and displacement thickness were greater for turbulent flow. Other ideas were examined in the discussions.
Content:
Abstract………………………………………………………………………………………………………………..…….…2
Introduction…………………………………………………………………………………………………………………..3
Background Theory………………………………………………………………………………………………………..3
Apparatus………………………………………………………………………………………………………………………5
Experimental Procedure…………………………………………………………………………………………………6
Results………………………………………………………………………………………..…………………………………7
Discussions…………………………….……………………………………………………..…………………….........12
Conclusion………………………………….…………………………………………………..…………………………..14
References……………………….…………………………………………………………………..……………..........14
Appendix……………………………………………………………………………………………………………………..15

Introduction: The flow past an object is an important study in aerodynamics. Close to the surface of the aerofoil, the flow behaves differently due to the presence of viscous forces. Due to viscous forces there is a presence of a boundary layer.…...

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