文档介绍：School of Jet Propulsion
Beihang University.
FLUID MECHANICS
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Chapter 1 Introduction
Preliminary Remarks
When you think about it, almost everything on this either is a fluid or moves within or near a fluid.
-Frank M. White
What is a
fluid?
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The concept of a fluid
A solid can resist a shear stress(剪切应力)
by a static deformation, a fluid can not.
Any shear stress applied to a fluid, no matter how small, will result in motion of that fluid.
The fluid moves and deforms continuously as long as the shear is applied.
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What is Fluid Mechanics
Fluid Mechanics is the study of fluid either in motion (Fluid Dynamics 流体动力学) or at rest(Fluid Statics 流体静力学) and subsequent effects of the fluid upon the boundaries, which may be either solid surfaces or interfaces with other fluids.
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The famous collapse of the a Narrow Bridge in 1940
Curved shoot (Banana shoot)
Nospin
Spin
why
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Boeing 747
×× (m)
395 000kg
An-225
84×× (m)
600,000kg
How can the airplane fly?
Drag & Lift
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The engine of a turbofan(涡扇) jet
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;
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History and Scope of Fluid Mechanics
Pre-history:
Sailing ships with oars(橹桨) and irrigation system were both known in prehistory
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