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Engineers' Practical Databook: A Technical Reference Guide for Students and
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ENGINEERS’
PRACTICAL DATABOOK
First Edition
ENGINEERS’ PRACTICAL DATABOOK
First Edition in SI Units
This Data Book is provided for the teaching of engineering and conforms to typical teaching structure for
selected modules within HNC, HND, Foundation Degree and Bachelor’s Degree qualifications in
Engineering.
Cover: “Azure Blue McLaren P1” by Axion23, cropped, is licenced under CC BY 2.0. “F-35 Front profile
in flight” by MSgt John Nimmo Sr. public domain cropped, from defenseimagery.mil. "The Severn
Bridge" by Martin Edwards is licensed under CC BY-SA 2.0. “Gear with terminology” is licenced under
CC BY-SA 3.0. “Sine and cosine” is public domain. “Mohr’s circle plane stress” by Sanpaz is licenced
under CC BY-SA 3.0. Unit Circle Angles by Gustavb is licenced under CC BY-SA 3.0. Material
properties derived or calculated from various sources, including Materials Handbook (ASM Vol.2, 1979),
th
Granta Design (2018), Thermodynamics: An Engineering Approach (Çengel & Boles, 6 ed., 2007),
www.engineeringtoolbox.com (2018), www.matweb.com (2018). Avogadro constant (2018 definition)
and atomic elements from IUPAC (2018). The author accepts no liability for any injuries or damages
caused that may result from the reader's acting upon or using the content contained in the publication.
Always consult a professional.
Whilst every care has been taken to include accurate information, the author would appreciate any
corrections to be sent to EngineersDatabook@gmail.com, quoting the page number.
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise
without either the prior written permission of the author or a licence permitting restricted copying in the
United Kingdom issued by the aforementioned.
All formulae are written in SI units (m, kg, s) unless otherwise explicitly stated.
Full Textbook:
USA:
https://www.amazon.com/dp/1980619344
UK:
https://www.amazon.co.uk/dp/1980619344
Copyright © 2018 Jay Smith
All rights reserved.
ISBN: 978-198-061934-5
Brief Contents
Symbols ................................................................................................................ 1
Units of Measurement .......................................................................................... 2
Mathematical Constants ....................................................................................... 4
Physical Constants ................................................................................................ 4
Conversion Factors ................................................................................................ 5
1.
Mathematics .................................................................................................. 9
2.
Materials ..................................................................................................... 55
3.
Mechanics .................................................................................................... 83
4.
Structures .................................................................................................... 91
5.
Machines and Mechanisms ........................................................................ 101
6.
Electrical and Electronics ............................................................................ 111
7.
Thermodynamics ....................................................................................... 127
8.
Fluid Mechanics ......................................................................................... 137
9.
Systems ..................................................................................................... 149
10. Project Management ................................................................................. 153
Properties of Water .......................................................................................... 157
Atmosphere ...................................................................................................... 158
Contents
Symbols ...................................... 1
Units of Measurement ................ 2
Prefixes ........................................ 2
S.I. Units ........................................ 2
Derived Units ................................. 3
Mathematical Constants ............. 4
Physical Constants ...................... 4
Conversion Factors ..................... 5
1. Mathematics........................... 9
1.1.
Algebra ............................ 9
Laws of Exponents ........................... 9
e (the base of the natural logarithm)9
Laws of Logarithms ........................ 10
Polynomials ................................... 11
Partial Fractions ............................. 12
1.2.
Sequences and Series .... 13
Sum of First n Natural Numbers .... 13
Sum of First n Squared Natural
Numbers ........................................ 13
Sum of Arithmetic Progression ...... 13
Sum of Geometric Progression ...... 14
1.3.
Coordinate Systems ....... 15
1.4.
Complex Numbers ......... 16
Cartesian Form .............................. 16
Polar Form ..................................... 16
De Moivre’s Theorem .................... 17
1.5.
Power series .................. 18
Taylor Series .................................. 19
Maclaurin Series ............................ 19
1.6.
Fourier Series ................. 19
Fourier Series ................................. 20
1.7.
Trigonometry................. 21
Definitions ..................................... 21
Unit Circle Identities ...................... 21
Unit Circle Angles........................... 22
Trigonometric Identities ................ 23
Sinusoidal Waveforms ................... 24
Expansion of R sin ωt+θ ............... 25
Area of a Triangle........................... 25
Law of Sines and Cosines ............... 25
1.8.
Hyperbolic Functions ..... 26
1.9.
Vectors .......................... 27
Notation ........................................ 27
Vector Multiplication ..................... 28
Triple Products .............................. 29
Vector Calculus .............................. 29
1.10.
Matrices ........................ 30
Notation ........................................ 30
Rotation Matrices .......................... 31
Screw Matrix ................................. 31
Euler Angles ................................... 31
Determinant .................................. 32
Eigenvectors and Eigenvalues ........ 32
Matrix Inverse ............................... 33
1.11.
Calculus ......................... 34
Derivatives ..................................... 34
Integrals......................................... 34
Table of Derivatives ....................... 35
Surface of Revolution .................... 36
Volume of Revolution .................... 36
Time Average of a Function ........... 36
1.12.
Laplace Transforms ....... 37
Table of Laplace Transforms .......... 38
1.13.
Statistics ........................ 40
Discrete Random Variables ............ 40
Grouped Frequency Distribution ... 40
Linear Regression (Least Squares
Regression Line) ............................ 41
Pearson Product Moment
Correlation Coefficient .................. 42
Spearman’s Rank Correlation
Coefficient ..................................... 42
Combinatorics ............................... 43
Binomial Formula .......................... 44
Binomial Distribution ..................... 44
Poisson Distribution....................... 47
Normal Distribution ....................... 50
2. Materials ...............................55
2.1.
The Elements ................. 55
Periodic Table ................................ 59
Pure Metallic Solids – Mechanical . 60
Pure Metallic Solids – Thermal and
Electrical ........................................ 62
2.2.
Steels and Alloys ............ 64
2.3.
Alloys ............................. 67
2.4.
Polymers ........................ 71
2.5.
Specific Heat Capacity ... 74
2.6.
Ashby Charts .................. 75
2.7.
Composites .................... 78
Classifications................................. 78
Two-Phase Composites .................. 79
Fibre-Reinforced Composites ......... 79
Short Fibres, Random Orientation . 81
Discontinuous and Aligned Fibre
Composites .................................... 81
3. Mechanics ............................. 83
Stress-Strain Relationship .............. 83
Uniaxial Stress ................................ 84
Shear .............................................. 84
Triaxial Stress ................................. 85
3.1.
Mohr’s Circle .................. 87
For Plane Stress.............................. 87
Principle Stress ............................... 87
General Three-Dimensional Stress . 90
Yield Criteria................................... 90
4. Structures .............................. 91
4.1.
Bending of Beams .......... 91
Second Moment of Area ................ 91
Radius of Gyration ......................... 91
4.2.
The Bending Formula ..... 92
Plane Sections ................................ 93
4.3.
Linear Elastic Beams ...... 94
4.4.
Torsion of Shafts ............ 98
Max Shear Stress............................ 98
Torsional Stiffness .......................... 99
4.5.
Euler’s Buckling Criterion100
Euler Buckling Force ..................... 100
Euler Buckling Stress .................... 100
5. Machines and Mechanisms . 101
5.1.
Mechanisms ................. 101
Mobility (Gruebler’s Equation)..... 101
Grashof’s Criterion ....................... 101
5.2.
Classical Mechanics ..... 102
Linear Terms ................................ 102
Rotary Terms................................ 102
Derivatives of Linear Position....... 102
Derivatives of Angular Position .... 102
Kinematics.................................... 103
Kinetics......................................... 106
5.3.
Periodic motion ............ 109
Springs (Hooke’s Law) .................. 109
Dampers or Dashpots .................. 109
Simple Harmonic Motion ............. 109
Mass-Spring-Damper ................... 110
Simple Pendulum ......................... 110
5.4.
Lagrange’s Equation .... 110
6. Electrical and Electronics ..... 111
6.1.
Fundamentals of
Electromagnetism ...................... 111
Ohm’s Law ................................... 111
Resistance .................................... 111
Inductance ................................... 111
Capacitance ................................. 112
Stored Energy .............................. 112
Reactance .................................... 112
Complex Impedance .................... 113
6.2.
Transformers................ 114
Induced EMF ................................ 114
Ideal Transformers ....................... 114
6.3.
Electrical Machines ...... 115
Lorentz Force ............................... 115
DC Machines ................................ 115
AC Machines ................................ 116
6.4.
AC Power...................... 117
Single Phase ................................. 117
Balanced 3-Phase ......................... 117
Star-delta Conversions ................. 118
Complex Waveforms.................... 118
6.5.
Electronics .................... 119
Circuit Diagram Symbols .............. 119
Diodes .......................................... 120
Field Effect Transistors ................. 120
Bipolar Junction Transistors ......... 121
Bipolar Amplifier Configurations .. 122
Operational Amplifiers ................. 123
Logic Gates ................................... 124
Boolean Algebra ........................... 125
Resistor Colour Code Table .......... 126
7. Thermodynamics ................. 127
7.1.
First Law....................... 127
Internal Energy............................. 127
7.2.
Second Law .................. 128
7.3.
Ideal Gas Equations ..... 129
Ideal Gas Law ............................... 129
Combined Gas Law....................... 129
Specific Heat Capacities ............... 130
7.4.
Isentropic Processes in Gas
Turbines ..................................... 130
7.5.
Cycle Efficiency ............ 130
Ideal Cycle Efficiency ................... 131
7.6.
Heat Pumps and
Refrigeration .............................. 131
Coefficient of Performance .......... 131
7.7.
Carnot Cycle ................ 131
7.8.
Heat Transfer .............. 132
Sensible Heat ............................... 132
Conduction .................................. 132
Convection ................................... 132
Composite Slab or Laminate with
Fluid Boundaries .......................... 132
Solid Expansion ............................ 133
Work ............................................ 133
Power .......................................... 133
7.9.
Flow Equations ............ 134
Change in Enthalpy ...................... 134
Steady Flow Energy Equation (open
system) ........................................ 134
7.10.
Diffusion ...................... 135
Fick’s First Law of Diffusion.......... 135
Fick’s Second Law of Diffusion ..... 135
The Arrhenius Equation ............... 135
8. Fluid Mechanics ...................137
8.1.
Statics .......................... 137
Static Pressure ............................. 137
Buoyancy Force ........................... 137
Surface Tension ........................... 138
8.2.
Dynamics ..................... 139
Stagnation Pressure ..................... 139
Bernoulli’s Equation..................... 139
Mass Continuity ........................... 139
Dynamic Viscosity ........................ 139
Reynolds Number ........................ 140
Pipe Friction - D’Arcy’s Formula ... 140
Laminar Friction Factor ................ 140
Stokes Drag .................................. 140
Pipe Roughness............................ 141
K-Factor of a Pipe Fitting ............. 143
Mass Continuity (Control Volume)
..................................................... 144
Momentum Continuity (Control
Volume) ....................................... 144
Navier-Stokes Equation ............... 144
8.3.
Aerodynamics .............. 145
Lift and Drag Coefficient .............. 145
Induced Drag Coefficient ............. 145
Speed of Sound ............................ 145
Mach Number.............................. 145
Ram Air Recovery ........................ 146
8.4.
Jet Engines ................... 147
Propulsive Power ......................... 147
Thrust Specific Fuel Consumption 147
Propulsive Efficiency .................... 147
Thermal Efficiency ....................... 147
Overall Efficiency ......................... 147
9. Systems ...............................149
Transfer Function ........................ 149
First Order Systems ..................... 149
Response to a Step Input ............. 149
Second Order Systems ................. 150
10. Project Management .........153
Earned Value Analysis .................. 153
Performance Indices .................... 154
Properties of Water .................157
Atmosphere .............................158
International Standard Atmosphere 158
Troposphere Model ......................... 158
Standard Atmosphere Table ............ 159
SYMBOLS
Name
Uses
alpha
Angles, angular acceleration, thermal expansion coefficient
beta
Angles, coefficients
gamma Heat capacity ratio, kinematic viscosity, shear strain
š›¤ Gamma Circulation (fluid dynamics)
delta
āˆ† Delta
Difference, damping
Difference, determinant (matrix)
epsilon
Strain, permittivity (electromagnetism), electromotive force
(EMF), random error (regression), emissivity (thermodynamics)
eta
Efficiency
theta
Angle, temperature (thermodynamics)
κ kappa
Curvature (=1/R)
Thermal conductivity, wavelength, eigenvalue, parameter in the
lambda Poisson Distribution (mean, variance)
mu
Friction coefficient, dynamic viscosity
nu
Kinematic viscosity, Poisson’s ratio
rho
Mass density, resistivity (electrical), curvature (alternative to r)
šœŽ sigma
šœ tau
šœ‘ phi
Normal stress, standard deviation
Shear stress, torque, time constant (electronics)
Angles, heat flow, potential energy, magnetic flux
psi
Helix angle (gears), stream function (fluid dynamics)
omega
Angular velocity
Ω Omega Electrical resistance (ohm)
ζ
š“
zeta
Damping ratio
Area (m2), current (A)
Diameter (m)
Young’s modulus (Pa)
Shear modulus (Pa)
Mass moment of inertia (kg m2), area moment of inertia (m4)
Polar moment of inertia (m4)
Radius (m)
Volume flow rate (m3/s), heat flowrate (kW)
Volume (m3), velocity (m/s)
UNITS OF MEASUREMENT
PREFIXES
Symbol
Prefix
Multiplication factor
P
peta
1 000 000 000 000 000
T
tera
1 000 000 000 000
G
giga
1 000 000 000
M
mega
k
kilo
1 000
d
deci
0.1
c
centi
0.01
m
milli
0.001
μ
micro
0.000 001
n
nano
0.000 000 001
p
pico
0.000 000 000 001
9
1 000 000
−
−
−
−
−9
−
S.I. UNITS
Symbol
Unit
Quantity
m
metre
Length
kg
kilogram
Mass
[M]
s
second
Time
[T]
A
ampere
Electric current
[A]
K
kelvin
Temperature
[θ]
cd
candela
Luminous intensity
[I]
mole
Amount of substance
[N]
mol
Dimension
[L]
DERIVED UNITS
Quantity
Unit
Symbol
Force
newton
N
Pressure and Stress
pascal
Pa
Torque
newton-metre
Energy, Work, Heat
joule
J
Power
watt
W
Frequency
hertz
Hz
Plane angle
radian
rad
Solid angle
steradian
sr
Luminous flux
lumen
lm
Illuminance
lux
lx
Kinematic Viscosity
stokes
St
Dynamic Viscosity
poiseuille
Pl
Magnetic Flux
weber
Magnetic Flux Density
tesla
T
Electrical Capacitance
farad
F
Electrical Charge
coulomb
C
Electrical Conductance
siemens
S
Electrical Inductance
henry
H
Electrical Resistance
ohm
ļ—
Potential difference/
Electromotive force
volt
V
Base Units
−
−
Nāˆ™m
−
−
−
−
−
−
=
−
=
−
−
Wb
š“
−
−
−
−
−
−
š“−
š“−
š“āˆ™
−
−
š“
−
š“−
š“−
−
−
š“−
MATHEMATICAL CONSTANTS
Symbol
š‘–
Description
Value
.
…
Base of the natural logarithm
.
…
Ratio of circumference to
diameter of a circle
√−
°/
=
.
Imaginary unit
…°
Radian
PHYSICAL CONSTANTS
Description
Symbol Value
−
.
.
.
.
− 9
×
×
×
.
.
Speed of light in vacuum
−
−
−
−
/
×
.
−
−
−
−
×
−
š“−
Elementary charge (
+
Electric constant (permittivity of
free space, or vacuum
permittivity)
š“
Magnetic constant (permeability
of free space, or vacuum
permeability)
Standard gravity
−
Gravitational constant
Universal gas constant
−
Specific gas constant for dry air
−
Avogadro constant
1.
FLUID MECHANICS
1.1. STATICS
Static Pressure
The change in static pressure in a barotropic, compressible fluid is given by:
ā„Ž
Δ =− ∫
ā„Ž
For an incompressible fluid, this simplifies to:
=
=
ā„Ž=
š‘–
š‘–
š‘– [
ā„Ž
š‘–
ā„Ž š‘– ā„Ž
š‘–
−
]
š‘–
.
Δ =−
−
ā„Ž
Δā„Ž
[ ]
A barotropic fluid is one whose pressure and density are related by an equation of
state that does not contain temperature as a dependent variable.
The static pressure p2 in the manometer below is given by:
=
+
Δā„Ž +
šœŒ
=
=
′
š‘–
−
[
]
š‘
š‘–
Δā„Ž
−
.
Buoyancy Force
=
š‘–
š‘– [
]
=
Δā„Ž
š‘
š›„ā„Ž šœŒ
138
Fluid Mechanics
Surface Tension
=
š‘–
=
[
cos
−
]
≈
š¹
ā„Ž
šœƒ
(capillary action)
Needle supported by surface tension
=
SIDE
cos
šœƒ
ā„Ž
FRONT
šœƒ
šœƒ
šæ
Pressure of a drop or bubble
Liquid Drop
Hollow Bubble
š›¾
š‘ƒš‘– − š‘ƒš‘œ =
š‘…
š‘ƒš‘– − š‘ƒš‘œ =
(Two surfaces)
š‘ƒš‘œ
š‘ƒš‘–
š‘…
Surface tension [10-3 N m-1]
Fluid
Acetone (propanone)
š›¾
š‘…
C3H6O
23
Crude oil, light
Hydrocarbons
32
Crude oil, heavy
Hydrocarbons
37
Ethanol (Ethyl alcohol)
C2H6O
22.3
Ethylene glycol
C2H6O2
48.8
Mercury
Hg
465
Water
H2O
72.8
Properties are at 20ā„ƒ. For comparison, water at 100ā„ƒ has a surface tension of
59 × 10-3 N m-1.
Fluid Mechanics
139
1.2. DYNAMICS
Stagnation Pressure
=
š‘–
−
[
š‘Ž
=
š‘Ž š‘–
]
+
š‘Ž š‘–
š‘¦ š‘Ž š‘–
=
+
Bernoulli’s Equation
+
+
ā„Ž=
=
+
For inviscid, incompressible, steady, irrotational flow, the sum of stagnation pressure
and elevation pressure is constant along a streamline.
š‘Ž
+ā„Ž
The total head (i.e. internal energy) of a fluid is comprised of the static pressure head,
velocity head, and elevation head.
Mass Continuity
Ģ‡ = Ģ‡
=
š“=
āƒ—=
āƒ—āƒ— =
š‘–
[
š‘–
š‘–
[
−
]
]
š“
[
−
=
āƒ— āˆ™Ģ‚
=
]
ā„Ž
š‘–
Dynamic Viscosity
For an isotropic Newtonian fluid
šœ= ā„Ž
=
=
= š‘–
š‘–
š‘–
š‘–
[
š‘–
]
š‘–
[ ]=[
−
[
]
[ ]
−
šœ=
−
]
š“
āƒ— āˆ™Ģ‚
140
Fluid Mechanics
Reynolds Number
=
š‘–
= ā„Ž
= ā„Ž
š‘– š‘–
š‘– š‘–
š‘–
ā„Ž
=
Pipe Friction - D’Arcy’s Formula
Head loss through a pipe
ā„Ž =
Pressure loss through a pipe
=
−
š‘–
ā„Ž
āˆ† =
š‘– š‘–
š‘–
Head loss through a fitting
=
š‘– š‘–
,
ā„Žšæ =
š‘– š‘–
Laminar Friction Factor
ā„Ž
=
Stokes Drag
Flow past a sphere at Re<2
š‘Ž
∞
=
∞
š·
.
Fluid Mechanics
141
Pipe Roughness
Pipes (Material)
Drawn tubing (glass, brass, plastic)
Copper
Absolute Roughness
microns [ −šŸ” š’Ž]
1.5
1.5
Aluminium
1.5
PVC
1.5
Red brass
1.5
Fiberglass
5
Carbon steel or wrought iron
45
Stainless steel
45
Cast iron-asphalt dipped
120
Galvanized iron
150
Cast iron uncoated
250
Wood stave
100-200
Ductile iron
2,500
Concrete
300 – 3,000
Riveted steel
1,000 – 10,000
Fittings
L/D
Globe valve
340
Gate valve
8
Lift check valve
600
Swing check valve
50 – 100
Ball valve
6
Butterfly valve
35
Flush pipe entrance (sharp corner)
K=0.5
Flush pipe entrance (radius >0.15)
K=0.04
Pipe exit
K=1
Tee through
20
Tee branch flow
60
Elbow (90 degrees)
30
Elbow (45 degrees)
16
142
Fluid Mechanics
Fluid Mechanics
143
K-Factor of a Pipe Fitting
Fitting
45° Elbow
90° Elbow Curved
90° Elbow Square or Mitred
180° Bend
Tee, Run Through
Tee, as Elbow
Tee, as Elbow
Tee, Branching Flow
Gate valve
Diaphragm valve
Globe valve, Bevel Seat
Plug valve
Butterfly valve
Check valve
Types
Standard (R/D = 1)
Long Radius (R/D = 1.5)
Standard (R/D = 1)
Long Radius (R/D = 1.5)
Close Return
Branch Blanked
Entering in run
Entering in branch
Fully Open
3/4 Open
1/2 Open
1/4 Open
Fully Open
3/4 Open
1/2 Open
1/4 Open
Fully Open
1/2 Open
θ = 5°
θ = 10°
θ = 20°
θ = 40°
θ = 60°
θ = 5°
θ = 10°
θ = 20°
θ = 40°
θ = 60°
Swing
Disk
Ball
š‘²
0.4
0.2
0.8
0.5
1.3
1.5
0.4
1
1
1
0.2
0.9
4.5
24
2.3
2.6
4.3
21
6
9.5
0.1
0.3
1.6
17
206
0.2
0.5
1.5
11
118
2
10
70
144
Fluid Mechanics
Mass Continuity (Control Volume)
Integral Form
=
āƒ—=
āƒ—āƒ— =
š“=
=
š‘–
∫
+∫
š‘‰
āƒ— āˆ™ āƒ—āƒ—
š“=
The mass change within a control volume plus the mass flowing out of the surface of
the control volume equals zero.
For incompressible flows, there is no mass change term:
=∫
Differential Form
+∇āˆ™
āƒ— āˆ™ āƒ—āƒ—
š“=
š’– =
For incompressible flows, the divergence equals zero:
∇āˆ™
=
āƒ—
+∫
Momentum Continuity (Control Volume)
āƒ—
=
∫
š‘‰
Navier-Stokes Equation
š’–
āƒ— āƒ— āˆ™ āƒ—āƒ—
š“=
+ š’– āˆ™ ∇š’– = −∇ + ∇ š’– + š’ˆ
The Navier-Stokes Equations are analogous to Newton’s Second Law applied to an
infinitesimal unit volume. The LHS includes the material derivative and is analogous
to mass times acceleration. The RHS is analogous to net force.
The material derivative of an infinitesimal fluid packet is equal to the sum of the
negative pressure gradient, shear forces, and body forces.
Fluid Mechanics
145
1.3. AERODYNAMICS
Lift and Drag Coefficient
šæ
=
š‘–
š“=
[
šæ
=
∞
=
]
š“
=
šæ
=
š“
∞
š“
=
š“
Induced Drag Coefficient
š“ =
= š‘–
š‘–
š‘–
š‘– š‘–
šæ
=
š“
e is the wing span efficiency value by which the induced drag exceeds that of an
elliptical lift distribution, typically 0.95-0.99.
Speed of Sound
š‘– ā„Ž
š‘–
š‘– ā„Ž š‘–
š‘‡š‘– ā„Ž
š‘– š‘– ā„Ž
š‘–
.
[ ]
Mach Number
=
=
š‘–
[
−
]
[
−
.
]
−
=√
š‘–
−
š‘‡
š‘–
=
Air is generally considered incompressible below M = 0.3.
146
Fluid Mechanics
Ram Air Recovery
To calculate ideal ram air temperature and pressure recovery (e.g. NACA
scoops, engine intakes):
š‘‡š‘‡ = š‘‡ ( + (
š‘‡š‘‡ =
š‘‡
š‘–
š‘‡
ā„Ž
[ ]
š‘–
š‘– š‘– ā„Ž
š‘‡
=
( +(
.
š‘–
−
−
š‘–
)
)
š‘–
)
š›¾
š›¾−
)
š‘–
The actual recovery pressure is slightly less than the total pressure due to
losses:
Fluid Mechanics
147
1.4. JET ENGINES
Propulsive Power
š‘‡= ā„Ž
Ģ‡ =
∞ =
=
[ ]
[
ā„Ž
š‘–
=š‘‡āˆ™
−
]
− ]
[
š‘– [
∞
−
= Ģ‡
−
∞
āˆ™
∞
]
Thrust Specific Fuel Consumption
[
Ģ‡ =
−
=
]
Ģ‡
š‘‡
Propulsive Efficiency
=
Thermal Efficiency
=
=
=
š‘–
š‘–
š›¾−
š›¾
=
š‘–
[
[
−( )
]
]
Overall Efficiency
=
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š‘£
+ š‘£š‘’
∞
=
−( )
−š›¾
š›¾