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d'Alembert's Principle
Use in Calculation of Forces and Internal Stresses in Accelerated Motion, 94009
Damage
see
Fatigue Under Variable Amplitude Loading
Damage Tolerance
see
Crack Length
Dampers
To Control Duct Noise
see
Noise in Air-conditioning Duct Systems
Use to Improve Aircraft Lateral Control
see
Lateral Stability and Response
Damping
see also
Damping Ratio
Acoustic Radiation Damping
beams and plates, TM 183
Aircraft
wings, fuselages, TM 183
Buildings and Structures
discussion of sources and effect of amplitude, 83009
methods of measuring, 77032, 83009
methods of supplementing, 77032, 83009
methods of supplementing to reduce response of cylinders, 79025
model tests to determine, 83009
representation in response equations, 77032
Compendium of Vibration Damping Data for Aerospace Structures, TM 183
Discussion of Sources in Structures
acoustic (fluid), 91012
material (hysteretic), 91012
structural, 91012
Effect on Sound Power Radiation
from dynamically excited rectangular plate, 00002
Fibre-Reinforced Laminated Composite Plates
damping of composites, TM 183
program for damping, 85012
Linearised Coefficients for Hydrodynamic Axial Groove Journal Bearings
database, 95023
Materials Used to Increase Structural
effects of frequency and temperature on loss factor and modulus, 91012, 92001
values of specific damping capacity, 85012
variation of loss factor and modulus with frequency and temperature for specific, 92001
Measures for Linear Systems
conversion between, 67038
conversion between for small damping, 73011, 91012
definitions, 66013, 67038, 73011, 77032, 83009, 91012
Methods of Increasing Structural
general discussion, 91012
materials available for treatment, 91012, 92001
use of additional constrained or free layers, 91012
use of tuned dampers, 91012
Prediction of Damping
composite plates and honeycomb panels, TM 183
Relationship of Aerodynamic to Airforce Coefficients (Flutter Derivatives), 82020
Satellites
satellite launch vehicles, spacecraft, TM 183
Tube Bundles in Shell-and-Tube Heat Exchangers
in gas or liquid flows, 87019
Use of Layered Treatments to Increase Structural
damping treatments, TM 183
estimation of increase due to free layers, 91012, 91013
estimation of increase due to multiple constrained layers, 91012, 91013
estimation of increase due to single constrained layer, 91012, 91013
loss factor and modulus of specific layer materials, 92001
Use of Tuned Dampers to Increase Structural, 91012
Values of Acoustic
for suppression of resonance in crossflow through tube banks, 88028
Damping Angle
Definition for Linear System, 67038
Damping Coefficient
Linear System
see also
Critical Damping Coefficient
definition, 66013
Damping Index
Definition for Linear System, 67038
Damping Materials
Use to Provide Additional Structural Damping, 91012
effects of frequency and temperature on loss factor and modulus, 91012
Variation of Loss Factor and Modulus With Frequency and Temperature for Specific, 92001
Damping Ratio
Aerodynamic Contribution
buildings and structures, 83009, 87035, 88019, 89049
Foundation Contribution
brief discussion of soil/structure interaction, 83009
Linear System
definition, 66013, 67038, 73011, 77032, 83009, 91012
Relationship With Loss Factor Used in Statistical Energy Analysis, 99009
Structural Contribution
approximate data, 77032, 87035, 88019, 91001, 96031
estimation for first translational mode of tall buildings, 83009, 91001
estimation for torsional and second-order translational modes of tall buildings, 91001
Typical Values
composite panels, 91012, TM 183
honeycomb sandwich panels, 73011, 91012, TM 183
stiffened panels, 73011, 91012, 99009, TM 183
Use as Parameter Defining Dynamical Similarity, 77032
inclusion in stability parameter, 79025
Variation With Frequency
curved or flat riveted skin-stringer panels, 73011
honeycomb sandwich panels, 73011, TM 183
integrally-machined panels, 73011
Data Analysis
see
Beta Functions
Curve Fitting
Regression
Similarity Laws
Statistics
Deadzone
Representation by Describing Functions in Analysis of Non-Linear System, 84009
Decelerators
see
Parachutes
Decomposition Analysis
Shell-and-Tube Heat Exchanger Network Design Using Process Integration
optimisation of costs and utility consumption, 00043
Degrees of Freedom
Statistics
definition, 91017, 91041, 92040
Delamination
Criterion for Prediction in Composite Plates From Interlaminar Stresses at Free Edges, 95028
comparison with experimental data for specific cases, 95028
Criterion for Prediction Under Through-Thickness Stresses, 94019
Detection by Non-Destructive Examination
selection of method and minimum detectable flaw, 91027
In Laminated Plates Tapered in Thickness by Ply Drop-Off
program to predict uniaxial load for, 91003
use of fracture mechanics to predict, 91003
In Specially-Orthotropic Corner Section
program to predict bending moment, radial shear and tangential direct load for, 94019
Delay Times
see
Abandoned Take-off
Landing
Delta Wings
see also
Indicial Aerodynamics
Slender Wings
Wing-body Combination
Wings
Contribution to Airframe Noise, 90023
Rolling Moment Due to Rollingat Supersonic Speeds
effect of interference from cylindrical body, AERO A.S.06.03.02
used in three- or four-wing arrangements, AERO A.S.06.03.01, AERO A.S.06.03.03
Sharp-Edged Cropped or Uncropped of Low Aspect Ratio
centre of pressure in subsonic flow, 95022
normal force and pitching moment in supersonic flow, 90013
normal force in subsonic flow, 93034
Density
see also
Air
Various Ceramic, Metallic and Polymer Materials, 84041
Various Liquids, 83046, 87027
Various Metallic Materials
aluminium, copper, magnesium and titanium alloys, and nickel steels and steels 00932 (MMDH)
Various Synthetic Lubricants, 94020
Depression
Description of Characteristics and Formation in Atmosphere, 87034
Derivatives
see also
Hinge Moment
Axes Transformation, 67004, 86041
Comparison of Alternative Definitions and Notation, 86021
Concept and Definition, 67003, 77032, 86021
Force Variation With Incidence
beam sections, bridge decks and buildings, 93013
Lift-Curve Slope (Z sub w, C sub L alpha or C sub z alpha)
see
Lift-curve Slope
Longitudinal
calculation from force and moment coefficients, 86021
Notation, 67001, 67002, 67003, 86021
Pitching Moment Due to Acceleration in Heave (M sub w dot or C sub m alpha dot)
forebody-cylinders, low incidence/supersonic speeds, with or without boat-tailing and fins, 91004
Pitching Moment Due to Heave (M sub w or C sub m alpha)
forebody-cylinders with boat-tailing at Mach Numbers up to 5, 87033, 89008
forebody-cylinders without boat-tailing at Mach Numbers up to 5, 89008
Pitching Moment Due to Rate of Pitch (M sub q or C sub mq)
accuracy of prediction for wing/body/tail combination, 90010
contribution due to body at subsonic speeds, 90010
contribution due to tailplane and wing at subsonic speeds, 90010
contribution due to wing at supersonic speeds, AERO W.S.08.03.02
effect of wing/body interference at subsonic speeds, 90010
forebody-cylinders, low incidence/supersonic speeds, with or without boat-tailing and fins, 91004
Rolling Moment Due to Aileron Deflection (L sub xi or C sub l delta a)
estimation at low speeds, 88013, 88040
Rolling Moment Due to Rate of Roll (L sub p or C sub lp), AERO A.06.01.00
contribution due to dihedral, 85006
contribution due to single fin/tailplane combination, 83006
contribution due to wing, AERO A.06.01.01
contribution due to wing at supersonic speeds, AERO A.S.06.03.01
effect of interference on wing from cylindrical body at supersonic speeds, AERO A.S.06.03.02
example of calculation for complete aircraft, 85010
three- or four-wing arrangements on cylindrical body, AERO A.S.06.03.01, AERO A.S.06.03.03
use of component contributions in prediction for complete aircraft, 85010
Rolling Moment Due to Rate of Yaw (L sub r or C sub lr), AERO A.06.01.00
bibliography on contribution due to wing in separated flow, 72021
contribution due to fin, 82017
contribution due to flaps, 72021
contribution due to wing in attached flow, 72021
example of calculation for complete aircraft, 84002
use of component contributions in prediction for complete aircraft, 84002
Rolling Moment Due to Rudder Deflection (L sub zeta or C sub l delta r)
estimation at low speeds, 87008
Rolling Moment Due to Sideslip (L sub v or C sub l beta), AERO A.06.01.00
accuracy of prediction for complete aircraft, 81032
comparison of experimental and predicted variation with incidence, 81032
contribution due to body, 00025, 73006
contribution due to flaps, 00025, 80034
contribution due to full-span dihedral, 00025, AERO A.06.01.03
contribution due to nacelles (on wing for propeller driven aircraft), 00025, TM 178
contribution due to nacelles (turbine engine rear-fuselage mounted), 73006
contribution due to nacelles (turbine engine underwing), 00025, 73006
contribution due to part-span dihedral, 00025, AERO A.06.01.09
contribution due to single fin (fuselage height/width near unity), 00025, 82010
contribution due to single fin merging into fuselage, AERO C.01.01.01
contribution due to single or twin fins (range of fuselage height/width), 93007
contribution due to tailplane-mounted twin fins, 92007
contribution due to wing in attached flow, 00025, 80033
effect of propellers, 06012
effect of wing-body geometry and wing position, 00025, 73006
examples of calculation for complete aircraft, 00025, 81032
program to calculate for complete aircraft, 00025
tailplane effects, 00025, 81032, 82010, 93007
use of component contributions in prediction for complete aircraft, 00025, 81032
Rolling Moment Due to Spoiler Deflection
see
Spoilers
Sideforce Due to Rate of Roll (Y sub p or C sub yp), AERO A.07.01.00
contribution due to dihedral, 85006
contribution due to single fin/tailplane combination, 83006
contribution due to wing (zero camber, dihedral and twist), 81014
example of calculation for complete aircraft, 85010
use of component contributions in prediction for complete aircraft, 85010
Sideforce Due to Rate of Yaw (Y sub r or C sub yr), AERO A.07.01.00
contribution due to body, 83026
contribution due to fin, 82017
example of calculation for complete aircraft, 84002
use of component contributions in prediction for complete aircraft, 84002
Sideforce Due to Rudder Deflection (Y sub zeta or C sub y delta r)
estimation at low speeds, 87008
Sideforce Due to Sideslip (Y sub v or C sub y beta), AERO A.07.01.00
accuracy of prediction for complete aircraft, 82011
contribution due to flaps, 00025, 81013
contribution due to nacelles (on wing for propeller driven aircraft), 00025
contribution due to nacelles (turbine engine rear-fuselage mounted), 79006
contribution due to nacelles (turbine engine underwing), 00025, 79006
contribution due to single fin (fuselage height/width near one), 00025, 82010
contribution due to single fin merging into fuselage, AERO C.01.01.01
contribution due to single or twin fins at supersonic speeds, 91031
contribution due to single or twin fins (range of fuselage height/width), 93007
contribution due to single or twin ventral fins at subsonic or supersonic speeds, 92029
contribution due to tailplane-mounted twin fins, 92007
discussion of contribution due to tailplane, 82011
effect of wing-body-tailplane interference on fin contribution at supersonic speeds, 91031
estimation for wing-body combination, 00025, 79006
examples of calculation for complete aircraft, 00025, 82011
program to calculate for complete aircraft, 00025
tailplane effects, 00025, 81032, 82010, 93007
use of component contributions in prediction for complete aircraft, 00025, 82011
Yawing Moment Due to Aileron Deflection (N sub xi or C sub n delta a)
estimation at low speeds, 88029, 88040
Yawing Moment Due to Rate of Roll (N sub p or C sub np), AERO A.07.01.00
contribution due to dihedral, 85006
contribution due to single fin/tailplane combination, 83006
contribution due to wing (zero camber, dihedral and twist), 81014
example of calculation for complete aircraft, 85010
use of component contributions in prediction for complete aircraft, 85010
Yawing Moment Due to Rate of Yaw (N sub r or C sub nr), AERO A.07.01.00
bibliography on contribution due to wing in separated flow, 71017
contribution due to body, 83026
contribution due to fin, 82017
contribution due to flaps, 71017
contribution due to wing in attached flow, 71017
example of calculation for complete aircraft, 84002
use of component contributions in prediction for complete aircraft, 84002
Yawing Moment Due to Rudder Deflection (N sub zeta or C sub n delta r)
estimation at low speeds, 87008
Yawing Moment Due to Sideslip (N sub v or C sub n beta), AERO A.07.01.00
accuracy of prediction for complete aircraft, 82011
contribution due to flaps, 00025, 81013
contribution due to nacelles (on wing for propeller driven aircraft), 00025
contribution due to nacelles (turbine engine rear-fuselage mounted), 79006
contribution due to nacelles (turbine engine underwing), 00025, 79006
contribution due to single fin (fuselage height/width near one), 00025, 82010
contribution due to single fin merging into fuselage, AERO C.01.01.01
contribution due to single or twin fins at supersonic speeds, 91031
contribution due to single or twin fins (range of fuselage height/width), 93007
contribution due to single or twin ventral fins at subsonic or supersonic speeds, 92029
contribution due to tailplane-mounted twin fins, 92007
effect of wing-body-tailplane interference on fin contribution at supersonic speeds, 91031
estimation for wing-body combination, 00025, 79006
examples of calculation for complete aircraft, 00025, 82011
program to calculate for complete aircraft, 00025
tailplane effects, 00025, 81032, 82010, 93007
use of component contributions in prediction for complete aircraft, 00025, 82011
Yawing Moment Due to Spoiler Deflection
see
Spoilers
Z-Force Due to Rate of Pitch (Z sub q or C sub zq)
contribution due to tailplane and wing at subsonic speeds, 90010
contribution due to wing at supersonic speeds, AERO W.S.08.03.02
effect of wing/body interference at subsonic speeds, 90010
Derv
see
Diesel Fuels
Descent
see
Cabin Conditions
Range
Rate of Descent
Describing Functions
Use in Nonlinear System Analysis
for closed-loop response to sinusoidal input, 84032
for stability determination and prediction of limit cycles, 84009
to represent backlash, deadzone, ideal relay, hysteresis or saturation, 84009
various types, 84009
worked examples, 84009, 84032
Design
Aerofoil Optimisation Examples (Multivariate Gradient Search Using CFD Codes)
introduction to method, 99019
varying camber line shape and high-lift device deflections (two design points), 99021
varying camber line shape or high-lift device deflections (single design point), 99020
varying high-lift device deflections on combat aircraft section (single design point), 00022, 00023
varying surface geometry and high-lift device deflections (two design points), 01024
Aerofoils for Low Drag Over a Range of Lift Coefficient
by maintaining favourable pressure gradient on forward upper and lower surfaces, 99003
Aerofoils to Provide Specified Upper-Surface Pressure Distribution in Transonic Flow, 99032
Allowable Stresses
see
Allowable Stresses
Control Systems
see
Control Systems
Estimation of Loads, SS1
Guide to Aerodynamic Considerations for Wings in Transonic Flow, 97017
Guide to Use of Data Items on Analysis and Design of Cam/Follower Mechanisms, 01002, 94017
Guide to Use of Winglets on Wings
as additions to existing designs or incorporated at wing design initiation, 98013
In Relation to Acoustic Fatigue
aircraft structures, 74037, 86025
detail aspects, 86025
In Relation to Fatigue
aircraft structures, 70018
design to fatigue limit, 75022
general principles, 71009
Inverse Aerofoil Examples (Multivariate Gradient Search Using CFD Codes)
to obtain complete or partial target pressure distribution, 01025
Need to Take Into Account Effects of Using Shot Peening, 92015
Need to Take Into Account Requirements for Non-Destructive Examination Methods, 91027
Safety Factors
see
Safety Factors
Use of Stress Analysis Items, SS1
Design Atmosphere
see
Atmosphere
Determinantal Equation
see
Characteristic Equation
Diagonal Tension Field
see
Curved Panels
Flat Panels in General
Diaphragms
see
Plates
Diaphragm Valves
Pressure Drop Across in Single-Phase Flow, 69022, 89012
Pressure Drop Across in Two-Phase Gas- or Vapour-Liquid Flow, 89012
Dichlorobenzene
see also
Heat Pipes
Density
pressure and temperature variation for saturated gas and liquid, 80017
Dynamic Viscosity
pressure and temperature variation for saturated gas and liquid, 80017
Specific Heat Capacity
pressure and temperature variation for saturated liquid, 80017
Specific Latent Heat of Vaporisation
pressure and temperature variation at saturation, 80017
Surface Tension
pressure and temperature variation at saturation, 80017
Thermal Conductivity
pressure and temperature variation for saturated liquid, 80017
Vapour Pressure
pressure and temperature variation at saturation, 80017
Diesel Engines
Incorporation in Process Plant as Heat and Power Source Using Process Integration Techniques, 89001
Diesel Fuels
Density
typical values, 71003
Dynamic Viscosity
typical values, 66024, 71003
Kinematic Viscosity
typical values, 66024, 71003
Diester
see
Lubricants
Differential Equations
see also
Linear Systems
Numerical Solution of First-Order With Initial Conditions
formulae for predictor-corrector method, 86011
formulae for Runge-Kutta method, 86011
Reduction of Higher-Order to First-Order, 74019, 80018, 86011
Solution by Laplace Transform, 69025
Differential Pressure Flowmeters
Pressure Drop Across, 66030
Diffusers
see also
Annular Diffusers
Conical Diffusers
Plane-walled Diffusers with Single-plane Expansion
Design Recommendations for Methods of Improving Performance
axial or tangential blowing or boundary layer suction, 87015
guidance on selection of appropriate method, 87015
guide vanes or splitters, 87015
hybrid diffusers, 87015
roughness or transverse ribs, 87015
screens or perforated plates, 87015
vortex generators, 87015
Discussion of Performance Measures and Their Presentation, 76027
Effectiveness
definition, 76027
Effect of Various Flow Parameters on Performance
inlet swirl, 76027
Mach number and Reynolds number, 76027
turbulence, 76027
various upstream velocity profiles, 76027
Effect of Various Geometry Changes on Performance
addition of tailpipe, 76027
bibliography on centre line curvature, 76027
cross section shape and its variation along diffuser, 76027
internal obstructions, 87015
moving walls, 87015
truncation, 76027, 87015, TM 19
wall curvature, 76027, 87015
Efficiency
definition, 76027
Ideal Pressure Recovery
definition, 76027
Interference From Adjacent Components, 76027
Review of Calculation Methods, 76027
Static Pressure Recovery in Compressible Flow
definition of coefficients, 90025
Static Pressure Recovery in Incompressible Flow
definition of coefficients, 73024, 74015, 75026, 76027, 87015
relative effects of inefficient and insufficient diffusion, 76027, TM 19
Total Pressure Loss in Compressible Flow
approximate derivation from static pressure recovery, 90025
Total Pressure Loss in Incompressible Flow
definition of coefficient, 73024, 74015, 75026, 76027, 87015
relation with static pressure recovery, 73024, 74015, 75026, 76027, 87015
Diffusion
Stress Analysis
see
Flat Panels in General
Diffusivity
see
Thermal Diffusivity

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