Aircraft aerodynamic design : geometry and optimization / András Sóbester, Alexander Forrester.

Format:

Book

Author/Creator:

Sóbester, András, author.

Forrester, Alexander I. J., author.

Series:

Aerospace series (Chichester, England).

THEi Wiley ebooks.

Aerospace Series

THEi Wiley ebooks

Language:

English

Subjects (All):

Airframes.

Aerodynamics.

Physical Description:

1 online resource (246 p.)

Edition:

1st ed.

Place of Publication:

Chichester, England : Wiley, 2015.

System Details:

Access using campus network via VPN at home (THEi Users Only).

Summary:

"Optimal aircraft design is impossible without a parametric representation of the geometry of the airframe. We need a mathematical model equipped with a set of controls, or design variables, which generates different candidate airframe shapes in response to changes in the values of these variables. This model's objectives are to be flexible and concise, and capable of yielding a wide range of shapes with a minimum number of design variables. Moreover, the process of converting these variables into aircraft geometries must be robust. Alas, flexibility, conciseness and robustness can seldom be achieved simultaneously.Aircraft Aerodynamic Design: Geometry and Optimization addresses this problem by navigating the subtle trade-offs between the competing objectives of geometry parameterization. It beginswith the fundamentals of geometry-centred aircraft design, followed by a review of the building blocks of computational geometries, the curve and surface formulations at the heart of aircraft geometry. The authors then cover a range of legacy formulations in the build-up towards a discussion of the most flexible shape models used in aerodynamic design (with a focus on lift generating surfaces). The book takes a practical approach and includes MATLAB(r), Python and Rhinoceros(r) code, as well as 'real-life' example case studies.Key features: Covers effective geometry parameterization within the context of design optimization Demonstrates how geometry parameterization is an important element of modern aircraft design Includes code and case studies which enable the reader to apply each theoretical concept either as an aid to understanding or as a building block of their own geometry model Accompanied by a website hosting codes Aircraft Aerodynamic Design: Geometry and Optimization is a practical guide for researchers and practitioners in the aerospace industry, and a reference for graduate and undergraduate students in aircraft design and multidisciplinary design optimization"-- Provided by publisher.

Contents:

Intro

AIRCRAFT AERODYNAMIC DESIGN

Contents

Series Preface

Preface

1 Prologue

2 Geometry Parameterization: Philosophy and Practice

2.1 A Sense of Scale

2.1.1 Separating Shape and Scale

2.1.2 Nondimensional Coefficients

2.2 Parametric Geometries

2.2.1 Pre-Optimization Checks

2.3 What Makes a Good Parametric Geometry: Three Criteria

2.3.1 Conciseness

2.3.2 Robustness

2.3.3 Flexibility

2.4 A Parametric Fuselage: A Case Study in the Trade-Offs of Geometry Optimization

2.4.1 Parametric Cross-Sections

2.4.2 Fuselage Cross-Section Optimization: An Illustrative Example

2.4.3 A Parametric Three-Dimensional Fuselage

2.5 A General Observation on the Nature of Fixed-Wing Aircraft Geometry Modelling

2.6 Necessary Flexibility

2.7 The Place of a Parametric Geometry in the Design Process

2.7.1 Optimization: A Hierarchy of Objective Functions

2.7.2 Competing Objectives

2.7.3 Optimization Method Selection

2.7.4 Inverse Design

3 Curves

3.1 Conics and Bézier Curves

3.1.1 Projective Geometry Construction of Conics

3.1.2 Parametric Bernstein Conic

3.1.3 Rational Conics and Bézier Curves

3.1.4 Properties of Bézier Curves

3.2 Bézier Splines

3.3 Ferguson's Spline

3.4 B-Splines

3.5 Knots

3.6 Nonuniform Rational Basis Splines

3.7 Implementation in Rhino

3.8 Curves for Optimization

4 Surfaces

4.1 Lofted, Translated and Coons Surfaces

4.2 Bézier Surfaces

4.3 B-Spline and Nonuniform Rational Basis Spline Surfaces

4.4 Free-Form Deformation

4.5 Implementation in Rhino

4.5.1 Nonuniform Rational Basis Splines-Based Surfaces

4.5.2 Free-Form Deformation

4.6 Surfaces for Optimization

5 Aerofoil Engineering: Fundamentals

5.1 Definitions, Conventions, Taxonomy, Description

5.2 A 'Non-Taxonomy' of Aerofoils

5.2.1 Low-Speed Aerofoils.

5.2.2 Subsonic Aerofoils

5.2.3 Transonic Aerofoils

5.2.4 Supersonic Aerofoils

5.2.5 Natural Laminar Flow Aerofoils

5.2.6 Multi-Element Aerofoils

5.2.7 Morphing and Flexible Aerofoils

5.3 Legacy versus Custom-Designed Aerofoils

5.4 Using Legacy Aerofoil Definitions

5.5 Handling Legacy Aerofoils: A Practical Primer

5.6 Aerofoil Families versus Parametric Aerofoils

6 Families of Legacy Aerofoils

6.1 The NACA Four-Digit Section

6.1.1 A One-Variable Thickness Distribution

6.1.2 A Two-Variable Camber Curve

6.1.3 Building the Aerofoil

6.1.4 Nomenclature

6.1.5 A Drawback and Two Fixes

6.1.6 The Distribution of Points: Sampling Density Variations and Cusps

6.1.7 A MATLAB® Implementation

6.1.8 An OpenNURBS/Rhino-Python Implementation

6.1.9 Applications

6.2 The NACA Five-Digit Section

6.2.1 A Three-Variable Camber Curve

6.2.2 Nomenclature and Implementation

6.3 The NACA SC Families

6.3.1 SC(2)

7 Aerofoil Parameterization

7.1 Complex Transforms

7.1.1 The Joukowski Aerofoil

7.2 Can a Pair of Ferguson Splines Represent an Aerofoil?

7.2.1 A Simple Parametric Aerofoil

7.3 Kulfan's Class- and Shape-Function Transformation

7.3.1 A Generic Aerofoil

7.3.2 Transforming a Legacy Aerofoil

7.3.3 Approximation Accuracy

7.3.4 The Kulfan Transform as a Filter

7.3.5 Computational Implementation

7.3.6 Class- and Shape-Function Transformation in Optimization: Global versus Local Search

7.3.7 Capturing the Shared Features of a Family of Aerofoils

7.4 Other Formulations: Past, Present and Future

8 Planform Parameterization

8.1 The Aspect Ratio

8.1.1 Induced Drag

8.1.2 Structural Efficiency

8.1.3 Airport Compatibility

8.1.4 Handling

8.2 The Taper Ratio

8.3 Sweep

8.3.1 Terminology

8.3.2 Sweep in Transonic Flight.

8.3.3 Sweep in Supersonic Flight

8.3.4 Forward Sweep

8.3.5 Variable Sweep

8.3.6 Swept-Wing 'Growth'

8.4 Wing Area

8.4.1 Constraints on the Wing Area

8.5 Planform Definition

8.5.1 From Sketch to Geometry

8.5.2 Introducing Scaling Factors: A Design Heuristic and a Simple Example

8.5.3 More Complex Planforms and an Additional Scaling Factor

8.5.4 Spanwise Chord Variation

9 Three-Dimensional Wing Synthesis

9.1 Fundamental Variables

9.1.1 Twist

9.1.2 Dihedral

9.2 Coordinate Systems

9.2.1 Cartesian Systems

9.2.2 A Wing-Bound, Curvilinear Dimension

9.3 The Synthesis of a Nondimensional Wing

9.3.1 Example: A Blended Box Wing

9.3.2 Example: Parameterization of a Blended Winglet

9.4 Wing Geometry Scaling. A Case Study: Design of a Commuter Airliner Wing

9.5 Indirect Wing Geometry Scaling

10 Design Sensitivities

10.1 Analytical and Finite-Difference Sensitivities

10.2 Algorithmic Differentiation

10.2.1 Forward Propagation of Tangents

10.2.2 Reverse Mode

10.3 Example: Differentiating an Aerofoil from Control Points to Lift Coefficient

10.4 Example Inverse Design

11 Basic Aerofoil Analysis: A Worked Example

11.1 Creating the .dat and .in files using Python

11.2 Running XFOIL from Python

12 Human-Powered Aircraft Wing Design: A Case Study in Aerodynamic Shape Optimization

12.1 Constraints

12.2 Planform Design

12.3 Aerofoil Section Design

12.4 Optimization

12.4.1 NACA Four-Digit Wing

12.4.2 Ferguson Spline Wing

12.5 Improving the Design

13 Epilogue: Challenging Topological Prejudice

References

Index

EULA.

Notes:

Includes bibliographical references and index.

Description based on print version record.

ISBN:

9781523123407

1523123400

9781118534731

1118534735

9781118534748

1118534743

9781118534717

1118534719

OCLC:

893686414