Aerodynamic Shape Optimization Using Control Theory

Aerodynamic Shape Optimization Using Control Theory
Author: James John Reuther
Publisher:
Total Pages: 500
Release: 1996
Genre: Aerodynamics
ISBN:

Abstract: "Aerodynamic shape design has long persisted as a difficult scientific challenge due [sic] its highly nonlinear flow physics and daunting geometric complexity. However, with the emergence of Computational Fluid Dynamics (CFD) it has become possible to make accurate predictions of flows which are not dominated by viscous effects. It is thus worthwhile to explore the extension of CFD methods for flow analysis to the treatment of aerodynamic shape design. Two new aerodynamic shape design methods are developed which combine existing CFD technology, optimal control theory, and numerical optimization techniques. Flow analysis methods for the potential flow equation and the Euler equations form the basis of the two respective design methods. In each case, optimal control theory is used to derive the adjoint differential equations, the solution of which provides the necessary gradient information to a numerical optimization method much more efficiently then [sic] by conventional finite differencing. Each technique uses a quasi-Newton numerical optimization algorithm to drive an aerodynamic objective function toward a minimum. An analytic grid perturbation method is developed to modify body fitted meshes to accommodate shape changes during the design process. Both Hicks-Henne perturbation functions and B-spline control points are explored as suitable design variables. The new methods prove to be computationally efficient and robust, and can be used for practical airfoil design including geometric and aerodynamic constraints. Objective functions are chosen to allow both inverse design to a target pressure distribution and wave drag minimization. Several design cases are presented for each method illustrating its practicality and efficiency. These include non-lifting and lifting airfoils operating at both subsonic and transonic conditions."

Optimization and Computational Fluid Dynamics

Optimization and Computational Fluid Dynamics
Author: Dominique Thévenin
Publisher: Springer Science & Business Media
Total Pages: 301
Release: 2008-01-08
Genre: Technology & Engineering
ISBN: 3540721533

The numerical optimization of practical applications has been an issue of major importance for the last 10 years. It allows us to explore reliable non-trivial configurations, differing widely from all known solutions. The purpose of this book is to introduce the state-of-the-art concerning this issue and many complementary applications are presented.

New Design Concepts for High Speed Air Transport

New Design Concepts for High Speed Air Transport
Author: H. Sobieczky
Publisher: Springer Science & Business Media
Total Pages: 348
Release: 1997-05-21
Genre: Technology & Engineering
ISBN: 9783211828151

This book presents the challenges, the tools and the concepts for developing economically viable high speed civil transport aircraft under environmental constraints. Computational tools for aircraft design and optimization are outlined and application in an industrial environment is shown for new and innovative case studies.

The Variational Method for Aerodynamic Optimization Using the Navier-Stokes Equations

The Variational Method for Aerodynamic Optimization Using the Navier-Stokes Equations
Author:
Publisher:
Total Pages: 34
Release: 1997
Genre:
ISBN:

This report describes the formulation of an aerodynamic shape design methodology using a compressible viscous flow model based on the Reynolds Averaged Navier Stokes equations. The aerodynamic shape is described by a set of geometrical design variables. The design problem is formulated as an optimization problem stated in terms of an aerodynamic objective functional which has to be minimized. The design scheme employs a gradient based optimization algorithm in order to obtain the optimum values of the design variables. The gradient of the aerodynamic functional with respect to the design variables is computed by means of the variational method, which requires the solution of an adjoint problem. The formulation of the adjoint problem is described which leads to a set of adjoint equations and boundary conditions. Using the flow variables and the adjoint variables, an expression for the gradient has been constructed. Computational results are presented for an inverse problem of an airfoil. It will be shown that, starting from an initial geometry of the NACA 0012 airfoil, the target pressure distribution and geometry of a best fit of the RAE 2822 airfoil in a transonic flow condition has been reconstructed successfully.

Engineering Design Optimization

Engineering Design Optimization
Author: Joaquim R. R. A. Martins
Publisher: Cambridge University Press
Total Pages: 653
Release: 2021-11-18
Genre: Mathematics
ISBN: 110898861X

Based on course-tested material, this rigorous yet accessible graduate textbook covers both fundamental and advanced optimization theory and algorithms. It covers a wide range of numerical methods and topics, including both gradient-based and gradient-free algorithms, multidisciplinary design optimization, and uncertainty, with instruction on how to determine which algorithm should be used for a given application. It also provides an overview of models and how to prepare them for use with numerical optimization, including derivative computation. Over 400 high-quality visualizations and numerous examples facilitate understanding of the theory, and practical tips address common issues encountered in practical engineering design optimization and how to address them. Numerous end-of-chapter homework problems, progressing in difficulty, help put knowledge into practice. Accompanied online by a solutions manual for instructors and source code for problems, this is ideal for a one- or two-semester graduate course on optimization in aerospace, civil, mechanical, electrical, and chemical engineering departments.

Constrained Optimization and Optimal Control for Partial Differential Equations

Constrained Optimization and Optimal Control for Partial Differential Equations
Author: Günter Leugering
Publisher: Springer Science & Business Media
Total Pages: 622
Release: 2012-01-03
Genre: Mathematics
ISBN: 3034801335

This special volume focuses on optimization and control of processes governed by partial differential equations. The contributors are mostly participants of the DFG-priority program 1253: Optimization with PDE-constraints which is active since 2006. The book is organized in sections which cover almost the entire spectrum of modern research in this emerging field. Indeed, even though the field of optimal control and optimization for PDE-constrained problems has undergone a dramatic increase of interest during the last four decades, a full theory for nonlinear problems is still lacking. The contributions of this volume, some of which have the character of survey articles, therefore, aim at creating and developing further new ideas for optimization, control and corresponding numerical simulations of systems of possibly coupled nonlinear partial differential equations. The research conducted within this unique network of groups in more than fifteen German universities focuses on novel methods of optimization, control and identification for problems in infinite-dimensional spaces, shape and topology problems, model reduction and adaptivity, discretization concepts and important applications. Besides the theoretical interest, the most prominent question is about the effectiveness of model-based numerical optimization methods for PDEs versus a black-box approach that uses existing codes, often heuristic-based, for optimization.

Computational Aerodynamics

Computational Aerodynamics
Author: Antony Jameson
Publisher: Cambridge University Press
Total Pages: 627
Release: 2022-09
Genre: Science
ISBN: 1108837883

Learn the design and analysis of numerical algorithms for aerodynamics. Ideal for graduates, researchers, and professionals in the field.

Aircraft Aerodynamic Design

Aircraft Aerodynamic Design
Author: András Sóbester
Publisher: John Wiley & Sons
Total Pages: 276
Release: 2014-11-17
Genre: Technology & Engineering
ISBN: 0470662573

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®, Python and Rhinoceros® 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.

Derivative-Free and Blackbox Optimization

Derivative-Free and Blackbox Optimization
Author: Charles Audet
Publisher: Springer
Total Pages: 307
Release: 2017-12-02
Genre: Mathematics
ISBN: 3319689134

This book is designed as a textbook, suitable for self-learning or for teaching an upper-year university course on derivative-free and blackbox optimization. The book is split into 5 parts and is designed to be modular; any individual part depends only on the material in Part I. Part I of the book discusses what is meant by Derivative-Free and Blackbox Optimization, provides background material, and early basics while Part II focuses on heuristic methods (Genetic Algorithms and Nelder-Mead). Part III presents direct search methods (Generalized Pattern Search and Mesh Adaptive Direct Search) and Part IV focuses on model-based methods (Simplex Gradient and Trust Region). Part V discusses dealing with constraints, using surrogates, and bi-objective optimization. End of chapter exercises are included throughout as well as 15 end of chapter projects and over 40 figures. Benchmarking techniques are also presented in the appendix.

Advanced UAV Aerodynamics, Flight Stability and Control

Advanced UAV Aerodynamics, Flight Stability and Control
Author: Pascual Marqués
Publisher: John Wiley & Sons
Total Pages: 799
Release: 2017-07-11
Genre: Technology & Engineering
ISBN: 1118928687

Comprehensively covers emerging aerospace technologies Advanced UAV aerodynamics, flight stability and control: Novel concepts, theory and applications presents emerging aerospace technologies in the rapidly growing field of unmanned aircraft engineering. Leading scientists, researchers and inventors describe the findings and innovations accomplished in current research programs and industry applications throughout the world. Topics included cover a wide range of new aerodynamics concepts and their applications for real world fixed-wing (airplanes), rotary wing (helicopter) and quad-rotor aircraft. The book begins with two introductory chapters that address fundamental principles of aerodynamics and flight stability and form a knowledge base for the student of Aerospace Engineering. The book then covers aerodynamics of fixed wing, rotary wing and hybrid unmanned aircraft, before introducing aspects of aircraft flight stability and control. Key features: Sound technical level and inclusion of high-quality experimental and numerical data. Direct application of the aerodynamic technologies and flight stability and control principles described in the book in the development of real-world novel unmanned aircraft concepts. Written by world-class academics, engineers, researchers and inventors from prestigious institutions and industry. The book provides up-to-date information in the field of Aerospace Engineering for university students and lecturers, aerodynamics researchers, aerospace engineers, aircraft designers and manufacturers.