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MEE 401 AEE 501Aerodynamics

Introduction

Basic Aero Forces

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Aero Parameters of Interest

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Theories of LiftNewton's Sine-Squared Law

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Theories of LiftNewton's Sine-Squared Law, 2

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Theories of LiftBernoulli's Equation

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Theories of LiftBernoulli's Equation, 2

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Theories of LiftCirculation Theory of Lift

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Theories of LiftCirculation Theory of Lift, 2

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Sources of Drag

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Sources of DragInduced Drag

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Sources of DragWake Drag

Asymmetry:

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Sources of DragSkin Friction Drag

! So far: inviscid, ideal fluid flow! Real fluids characterized by frictional effects

!Viscous drag = resistance to moving body dueto surrounding (stationary) fluid

! Laminar Flow

! Turbulent FlowAerodynamics

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Transition

Aerodynamics

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IntroductionMiscellaneous: Airplane Controls Terminology

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General Analysis Procedure

! Typical analysis work flow

Aerodynamics

Physical Problem

IdentifyImportant

variables

Make reasonableassumptions and

approximations

Apply relevantphysical

principles

Mathematical Equation

Problem Solution

Use applicablesolution techniques

Apply suitableboundary and

initial conditions

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General Analysis Procedure-2

Aerodynamics

! Typical analysis process flow! Write out problem statement! Draw a problem schematic! State your assumptions and approximations! Apply all relevant basic physical laws & principles! Determine unknown properties at known states! Perform calculations to determine the unknowns!

Verify the validity of the results

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Summary

! What a fluid is.! Its properties. The governing laws

! Reynolds number. Mach number! How Newtons 2nd Law works as a vector equation! Ideal fluid (incompressible, inviscid, ideal gas)! Viscous effects: no-slip condition, boundary layer,

separation, wake, turbulence, laminar

! Compressibility effects: Regimes, shock waves,isentropic waves.! Initial ideas of concepts such as streamlines/eddies! Qualitative understanding

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Miscellaneous: Constitutive Relations

! Fouriers Law of Heat Conduction

! Newtons Law of Viscosity