Download or read book Design Optimization of Highly Flexible Aircraft with Aeroelastic Constraints written by Anil Variyar and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: With the need to drastically reduce aircraft emissions and fuel burn, there have been significant strides towards the design of fuel-efficient aircraft. This has involved moving towards extremely high aspect-ratio wings that need to be aeroelastically tailored and unconventional aircraft configurations. However aeroelastic stability of such configurations is a major challenge. In order to ensure that the fuel-burn improvements predicted in the conceptual or early preliminary design phase are attained in reality, it is essential to ensure that aeroelastic constraints are enforced early on in the design phase itself. However inexpensive yet accurate computation of transonic aeroelasticity especially transonic flutter predictions is quite a challenge due to the non-linearity in the flow at transonic regimes which requires non-linear fluid dynamics approaches that are generally too expensive for the early design phases. In this work we attempt to address this issue by first developing a two-dimensional parametric transonic low-order model that accurately predicts unsteady flow results for airfoils. A set of airfoil agnostic parameters for this model are obtained that permit accurate two-dimensional transonic aeroelastic simulations. This approach is then extended into three dimensions using the ASWING Weissinger model formulation. Next a set of in-house capabilities are developed that permit the inclusion of this approach into a conceptual design loop. Finally a number of flutter constrained optimizations are performed to understand the impact of imposing flutter constraints in an aircraft design/sizing loop.
Download or read book Multidisciplinary Design Optimization of Aircraft Wing Structures with Aeroelastic and Aeroservoelastic Constraints written by Sang-Young Jung and published by . This book was released on 1999 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aircraft Aerodynamic Design written by András Sóbester and published by John Wiley & Sons. This book was released on 2014-11-17 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Multidisciplinary Design Optimization of A Highly Flexible Aeroservoelastic Wing written by Sohrab Haghighat and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book WIDOWAC Wing Design Optimization with Aeroelastic Constraints written by Raphael T. Haftka and published by . This book was released on 1974 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AeroStruct Enable and Learn How to Integrate Flexibility in Design written by Ralf Heinrich and published by Springer. This book was released on 2018-01-30 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reports on the German research initiative AeroStruct, a three-year collaborative project between universities and the aircraft industry. It describes the development of an integrated multidisciplinary simulation environment for aircraft analysis and optimization using high-fidelity methods. This system is able to run at a high level of automatism, thus representing a step forward with respect to previous ones. Its special features are: a CAD description that is independent from the disciplines involved, an automated CFD mesh generation and an automated structure model generation including a sizing process. The book also reports on test cases by both industrial partners and DLR demonstrating the advantages of the new environment and its suitability for the industry. These results were also discussed during the AeroStruct closing Symposium, which took place on 13-14 October 2015 at the DLR in Braunschweig, Germany. The book provides expert readers with a timely report on multidisciplinary aircraft design and optimization. Thanks to a good balance between theory and practice, it is expected to address an audience of both academics and professional, and to offer them new ideas for future research and development.
Download or read book Principles of Aeroelasticity written by Ahmad Reza Ghasemi and published by . This book was released on 2018-06 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aeroelasticity refers to the science of the interaction between aerodynamic, inertial and elastic effects. Aeroelastic effects occur everywhere but are more or less critical. Any phenomenon that involves a structural response to a fluid action requires aeroelastic consideration. In many cases, when a large and flexible structure is submitted to a high intensity variable flow, the deformations can be very important and become dangerous. With the emphasis on higher performance, modern aircraft designs aim at lower structural weight, aerodynamically efficient thinner configurations, and reduced or even negative stability margins augmented by automatic flight control systems. These design considerations lead to highly flexible structural designs with associated problems of dynamic and aeroelastic interactions which need to be considered at the preliminary design stage itself. Development and application of wind turbines and the related issues such as structural design, aerodynamic design, and material selection as well as manufacturing issues, including fatigue, optimization, and aeroelastic stability have attracted researchers' attention.Principles Of Aeroelasticity presents the recent research and development efforts in the areas of aeroelastic tailoring, structural optimization with aeroelastic constraints and aeroservoelasticity, and applications of the same in practical designs. The developments and applications in these areas are also highlighted. Key topics in composite blades of wind turbines including design, stress analysis, aeroelasticity, and fatigue are studied. Numerical and analytical methods are applied for considering the flutter phenomenon of the blades. It covers the numerical calculation algorithm of the structured singular value, uncertainty model construction, robust aeroelastic stability analysis algorithms, uncertainty level verification, and robust flutter boundary prediction in the flight test, etc. Development and application of wind turbines and the related issues such as structural design, aerodynamic design, and material selection as well as manufacturing issues, including fatigue, optimization, and aeroelastic stability have attracted researchers' attention. It presents the detailed investigation of coupled-mode flutter and non-synchronous vibration in turbomachinery. Coupled-mode flutter and non-synchronous vibration are two aeromechanical challenges in designing turbomachinery that, when present, can cause engine blade failure.
Download or read book Introduction to Nonlinear Aeroelasticity written by Grigorios Dimitriadis and published by John Wiley & Sons. This book was released on 2017-03-10 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Nonlinear Aeroelasticity Introduces the latest developments and technologies in the area of nonlinear aeroelasticity Nonlinear aeroelasticity has become an increasingly popular research area in recent years. There have been many driving forces behind this development, increasingly flexible structures, nonlinear control laws, materials with nonlinear characteristics and so on. Introduction to Nonlinear Aeroelasticity covers the theoretical basics in nonlinear aeroelasticity and applies the theory to practical problems. As nonlinear aeroelasticity is a combined topic, necessitating expertise from different areas, the book introduces methodologies from a variety of disciplines such as nonlinear dynamics, bifurcation analysis, unsteady aerodynamics, non-smooth systems and others. The emphasis throughout is on the practical application of the theories and methods, so as to enable the reader to apply their newly acquired knowledge Key features: Covers the major topics in nonlinear aeroelasticity, from the galloping of cables to supersonic panel flutter Discusses nonlinear dynamics, bifurcation analysis, numerical continuation, unsteady aerodynamics and non-smooth systems Considers the practical application of the theories and methods Covers nonlinear dynamics, bifurcation analysis and numerical methods Accompanied by a website hosting Matlab code Introduction to Nonlinear Aeroelasticity is a comprehensive reference for researchers and workers in industry and is also a useful introduction to the subject for graduate and undergraduate students across engineering disciplines.
Download or read book Flexible Engineering Toward Green Aircraft written by Marco Evangelos Biancolini and published by Springer Nature. This book was released on 2020-03-13 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the recent advances in aircraft design methodologies. It provides an overview of topics such as shape optimization, robust design and aeroelasticity, focusing on fluid-structure numerical methodologies to address static and dynamic aeroelastic problems. It demonstrates that the capability to evaluate the interaction between aerodynamics, inertia and elastic forces is important to avoid drag penalties, control system efficiency loss and generation of potentially dangerous phenomena, such as divergence, control reversal and flutter. The book particularly highlights the advances in “high fidelity” CFD-CSM coupling, describing the latest experimental research to validate the numerical fluid-structure interaction analysis methodologies resulting from the EU-funded RBF4AERO and RIBES projects.
Download or read book Low Speed Aerodynamics written by Joseph Katz and published by Cambridge University Press. This book was released on 2001-02-05 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low-speed aerodynamics is important in the design and operation of aircraft flying at low Mach number, and ground and marine vehicles. This 2001 book offers a modern treatment of the subject, both the theory of inviscid, incompressible, and irrotational aerodynamics and the computational techniques now available to solve complex problems. A unique feature of the text is that the computational approach (from a single vortex element to a three-dimensional panel formulation) is interwoven throughout. Thus, the reader can learn about classical methods of the past, while also learning how to use numerical methods to solve real-world aerodynamic problems. This second edition has a new chapter on the laminar boundary layer (emphasis on the viscous-inviscid coupling), the latest versions of computational techniques, and additional coverage of interaction problems. It includes a systematic treatment of two-dimensional panel methods and a detailed presentation of computational techniques for three-dimensional and unsteady flows. With extensive illustrations and examples, this book will be useful for senior and beginning graduate-level courses, as well as a helpful reference tool for practising engineers.
Download or read book Investigation of the Helios Prototype Aircraft Mishap Volume I Mishap Report written by Thomas E. Noll and published by Createspace Independent Pub. This book was released on 2012-11-08 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Helios Prototype vehicle was one of several remotely piloted aircraft funded and developed by NASA under the Environmental Research Aircraft and Sensor Technology (ERAST) project, and managed by NASA's Dryden Flight Research Center (DFRC). This vehicle was a proof-of-concept, propeller-driven, flying wing built and operated by AeroVironment, Inc. The vehicle consisted of two configurations. One configuration, designated HP01, was designed to operate at extremely high altitudes using batteries and high-efficiency solar cells spread across the upper surface of its 247-foot wingspan. On 13 August 2001, this aircraft configuration reached an altitude of 96,863 feet, a world record for sustained horizontal flight by a winged aircraft. The other configuration, designated HP03, was designed for long-duration flight. The plan was to use the solar cells to power the vehicle's electric motors and subsystems during the day and to use a modified commercial hydrogen–air fuel cell system for use during the night. The vehicle was also equipped with batteries as a backup source of power. The aircraft design used wing dihedral, engine power, elevator control surfaces, and a stability augmentation and control system to provide aerodynamic stability and control. On 26 June 2003, HP03-2 took off at 10:06am local time from the Navy's Pacific Missile Range Facility (PMRF) located on the island of Kauai, Hawaii. The aircraft was under the guidance of AeroVironment, Inc. (AV) ground-based mission controllers. At that time the environmental wind conditions appeared to be within an acceptable envelope, and consisted of a wind shadow over and offshore from PMRF, bounded to the north, south, and above by zones of wind shear and turbulence separating this region from the ambient easterly trade-wind flow. However, compared to previous solar-powered flights from PMRF, HP03-2 was subject to longer exposure to the low-level turbulence in the lee of Kauai due to the shallower climb out trajectory. The vehicle's longer exposure to Kauai's lee side turbulence and lower shear line penetration were superposed on what the Board now recognizes as greater airplane sensitivity to turbulence and may have been compounded by the apparent narrow corridor between the shear lines noted by the chase helicopter observer. At 10:22am and 10:24am, the aircraft encountered turbulence and the wing dihedral became much larger than normal and mild pitch oscillations began, but quickly damped out. At about 30 minutes into the flight, the aircraft encountered turbulence and morphed into an unexpected, persistent, high dihedral configuration. As a result of the persistent high dihedral, the aircraft became unstable in a very divergent pitch mode in which the airspeed excursions from the nominal flight speed about doubled every cycle of the oscillation. The aircraft's design airspeed was subsequently exceeded and the resulting high dynamic pressures caused the wing leading edge secondary structure on the outer wing panels to fail and the solar cells and skin on the upper surface of the wing to rip off. The aircraft impacted the ocean within the confines of the PMRF test range and was destroyed. The crash caused no other property damage or any injuries to personnel on the ground. Most of the vehicle structure was recovered except the hydrogen-air fuel cell pod and two of the ten engines, which sank into the ocean. The root causes of the mishap include: Lack of adequate analysis methods led to an inaccurate risk assessment of the effects of configuration changes leading to an inappropriate decision to fly an aircraft configuration highly sensitive to disturbances, and Configuration changes to the aircraft, driven by programmatic and technological constraints, altered the aircraft from a spanloader to a highly point-loaded mass distribution on the same structure significantly reducing design robustness and margins of safety.
Download or read book Advanced Design Problems in Aerospace Engineering written by Angelo Miele and published by Springer Science & Business Media. This book was released on 2006-04-11 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Design Problems in Aerospace Engineering, Volume 1: Advanced Aerospace Systems presents six authoritative lectures on the use of mathematics in the conceptual design of various types of aircraft and spacecraft. It covers the following topics: design of rocket-powered orbital spacecraft (Miele/Mancuso), design of Moon missions (Miele/Mancuso), design of Mars missions (Miele/Wang), design of an experimental guidance system with a perspective flight path display (Sachs), neighboring vehicle design for a two-stage launch vehicle (Well), and controller design for a flexible aircraft (Hanel/Well). This is a reference book of interest to engineers and scientists working in aerospace engineering and related topics.
Download or read book Modeling and Control for a Blended Wing Body Aircraft written by Martin Kozek and published by Springer. This book was released on 2014-10-27 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book demonstrates the potential of the blended wing body (BWB) concept for significant improvement in both fuel efficiency and noise reduction and addresses the considerable challenges raised for control engineers because of characteristics like open-loop instability, large flexible structure, and slow control surfaces. This text describes state-of-the-art and novel modeling and control design approaches for the BWB aircraft under consideration. The expert contributors demonstrate how exceptional robust control performance can be achieved despite such stringent design constraints as guaranteed handling qualities, reduced vibration, and the minimization of the aircraft’s structural loads during maneuvers and caused by turbulence. As a result, this innovative approach allows the building of even lighter aircraft structures, and thus results in considerable efficiency improvements per passenger kilometer. The treatment of this large, complex, parameter-dependent industrial control problem highlights relevant design issues and provides a relevant case study for modeling and control engineers in many adjacent disciplines and applications. Modeling and Control for a Blended Wing Body Aircraft presents research results in numeric modeling and control design for a large, flexible, civil BWB aircraft in the pre-design stage as developed within the EU FP7 research project ACFA 2020. It is a useful resource for aerospace and control engineers as it shows the complete BWB aircraft modeling and control design process, carried out with the most recent tools and techniques available. presents research results in numeric modeling and control design for a large, flexible, civil BWB aircraft in the pre-design stage as developed within the EU FP7 research project ACFA 2020. It is a useful resource for aerospace and control engineers as it shows the complete BWB aircraft modeling and control design process, carried out with the most recent tools and techniques available. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series offers an opportunity for researchers to present an extended exposition of new work in all aspects of industrial control.
Download or read book The Role of Static Aero elastic Constraints in the Design Optimization of High Aspect Ratio Wings written by K. Emil Kadrnka and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Engineering Design Optimization written by Joaquim R. R. A. Martins and published by Cambridge University Press. This book was released on 2021-11-18 with total page 653 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Dynamics of Atmospheric Flight written by Bernard Etkin and published by Courier Corporation. This book was released on 2012-08-29 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt: This treatment for upper-level undergraduates, graduate students, and professionals makes special reference to stability and control of airplanes, with extensive numerical examples covering a variety of vehicles. 260 illustrations. 1972 edition.
Download or read book Introduction to Aircraft Aeroelasticity and Loads written by Jan R. Wright and published by John Wiley & Sons. This book was released on 2015-02-23 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Aircraft Aeroelasticity and Loads, Second Edition is an updated new edition offering comprehensive coverage of the main principles of aircraft aeroelasticity and loads. For ease of reference, the book is divided into three parts and begins by reviewing the underlying disciplines of vibrations, aerodynamics, loads and control, and then goes on to describe simplified models to illustrate aeroelastic behaviour and aircraft response and loads for the flexible aircraft before introducing some more advanced methodologies. Finally, it explains how industrial certification requirements for aeroelasticity and loads may be met and relates these to the earlier theoretical approaches used. Key features of this new edition include: Uses a unified simple aeroelastic model throughout the book Major revisions to chapters on aeroelasticity Updates and reorganisation of chapters involving Finite Elements Some reorganisation of loads material Updates on certification requirements Accompanied by a website containing a solutions manual, and MATLAB® and SIMULINK® programs that relate to the models used Introduction to Aircraft Aeroelasticity and Loads, Second Edition is a must-have reference for researchers and practitioners working in the aeroelasticity and loads fields, and is also an excellent textbook for senior undergraduate and graduate students in aerospace engineering.
