# UNITS, UNITS, UNITS (and after you have studied UNITS, study more UNITS!)

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27 Οκτ 2013 (πριν από 4 χρόνια και 8 μήνες)

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EMEC 368 Introduction to Aerospace

What You Need to Know for Test 1

Information comes to you for this class four different ways:

1)

Lectures

2)

Tours

3)

The textbook (including homeworks)

4)

Website

You are responsible for the information. If you miss something,
or me.

For solving problems on the test, you are responsible for the following:

Chapter 1 The First Aeronautical Engineers

General history leading to modern aircraft

Flight vehicle configurations

Controls

Powered

flight

Chapter 2 Fundamental Thoughts

UNITS, UNITS, UNITS (and after you have studied UNITS, study more UNITS
!
)

Unit mistakes are easy to make, can have large consequences, but are easy to avoid
.

Definitions and parameters

Pressure

Density

Temperature

Velocity

Newton’s laws (In English units, make sure you have the mass unit [slugs] correct)

Ideal gas law p = ρ RT; specific volume = 1/

ρ

Chapter 3 The Standard Atmosphere

Altitude Definitions

Absolute

Geometric

Geopotential

The Hydrostatic Equation dp =
-

ρ g dh
G

The Standard Atmosphere

Isothermal Layers

Equations of State

Pressure, Temperature (non
-
unique), and Density Altitudes

You
should have an ability

to understand, utilize and interpolate the St
andard Atmosphere
tables.

Chapter 4 Basic Aerodynamics

Basic Fluid Dynamics

Continuity

Momentum

Energy

Inviscid,
Incompressible Flow

A
1
V
1

= A
2
V
2

Euler’s Equation

Bernoulli’s Equation (energy)

Elementary Thermodynamics

δq + δw = de

δq

= de + pd
v

h = e + p
v

= e + RT

δq = dh

v
dp

de = c
v

dT

dh = c
p

dT

e = c
v

T

h = c
p

T

Isentropic Flow

Reversible

You should be able to manipulate and apply these equat
ions, with state variables
and ideal gas laws.

Speed of Sound a = (γRT)
1/2

Subsonic Flow

Compressibility Effects

Supersonic Flow (thermodynamics of a shock wave)

Supersonic Nozzles

Viscous Flow

Boundary Layer

Laminar

Turbulent

Forces (Drag

Skin Friction + Separation [pressure drag])

Compressibility Effects

Transition

Flow Separation

Summary of Equations

for Chapter 4,

pp. 277
-
280.

You should adroit in your ability to calculate basic fluid flows, correct for compressible
effects, solve

pitot
-
static type problems,
use

isentropic equations where applicable,
calculate boundary layers (including skin friction drag)

Chapter 5
Airfoils, Wings, and Other Aerodynamic Shapes

Airfoil nomenclature

Chord

Camber

Thic
kness

Relative Wind and Angle of Attack

Pressure Distributions, q

Lift and Drag

Resultants

Coefficients

Airfoil Data

Appendix D

c
l
, c
d
, c
m

c/4

Stall, Roughness, and Flap effects

Finite wings

Compressibility effects

Critical Mach number

Drag Divergence

Supersonic Flow

Wave drag

c
l
, c
d

Finite Wing

Induced Drag

Change in Lift Slope, α
e

The Drag Polar, C
D

vs. C
L

Swept Wings

Critical Mach number

Mach cone

Flaps

Influence on Lift and Drag

Stall
Speed

You should be able to calculate lift
and drag on Aerodynamic Shapes. This includes
compressibility corrections, transonic speeds, and supersonic speeds.

Chapter 6 Elements of Aircraft Performance

THROUGH SECTION 6.13 ONLY

The Drag Polar for actual
aircraft

Basic Equations of Motion

Along Flight Path F
ll

= m dV/dt

Perpendicular F

= m V
2
/r
c
, “centrifugal force”, curved path r
c

Thrust Required for Level, Unaccelerated Flight

A familiarity with our “example” airplanes

CP
-
1, Cessna 182

CJ
-
1,
Citation 3

Thrust Available and Maximum Velocity

Propeller Driven

Jet

Power Required for Level, Unaccelerated Flight

Propeller Driven

Jet

Power Available and Maximum Velocity

Propeller Driven

Jet

Altitude Effects

Rate of Climb

Gliding Flight

Absolut
e (R/C=0) and Service (R/C = 100 ft/min) Ceilings

Time to Climb

Range and Endurance

Propeller Driven, the Brequet
Formulas, Specific Fuel Consumption

Jet
, Thrust Specific Fuel Consumption

You should be able to integrate the concepts from Chapters 2
-
5 to

predict basic,
static performance (zero acceleration), through Range and Endurance
,

of flight
vehicle structures (through Section 6.13 in the textbook).