Download or read book Multidisciplinary Adjoint based Design Optimization Techniques for Helicopter Rotors written by Enrico Fabiano and published by . This book was released on 2017 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Helicopter rotor design optimization is a challenging task due to the multidisciplinary nature of rotorcraft design: the helicopter operates in a highly unsteady aerodynamic environment, highly flexible, slender rotor blades highlight the importance of blade aeroelasticity, while the ever more stringent noise requirements that the helicopter must satisfy underlines the need to include aeroa- coustic considerations early in the design process. Such a large scale problem can be efficiently solved with the use of gradient-based optimization methods. In gradient based optimization, the gradient of the objective function with respect to the design variables is needed to determine a search direction. The objective function’s gradient can be computed either with the finite difference approach, the tangent or forward linearization approach and the adjoint or reverse approach. The finite difference approach is easy to implement but its cost scales with the number of design variables and can be affected by the choice of the step size used in the differentiation. The tangent or forward approach computes the exact gradient vector of the objective function by exact differentiation of the computational code, however its cost still scales linearly with the number of design variables. On the other hand, the adjoint or reverse approach computes the sensitivity vector with respect to a potentially infinite number of design variables at a cost essentially independent of the design variables, making the adjoint technique the only viable approach when the number of design variables is large. Hence, it is the adjoint approach that makes gradient based optimization techniques competitive for large scale problems characterized by a large number of design parameters, such as the current helicopter design problem. The focus of this work is the development of a high-fidelity multidisciplinary adjoint technique that encompasses the three disciplines of aerodynamics, structural mechanics and aeroacoustics for ro- torcraft problems. Upon successful implementation and verification, the multidisciplinary adjoint method is applied to the problem of noise minimization of a flexible rotor in trimmed forward flight with no performance penalty. Optimization results highlight the potential of high-fidelity multidisciplinary design optimization for helicopter rotors.

Download or read book Multidisciplinary Optimization of Helicopter Rotor Blades Including Design Variable Sensitivity written by Thomas R. McCarthy and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Integrated Multidisciplinary Design Optimization of Rotorcraft written by Howard M. Adelman and published by . This book was released on 1989 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Impact of Structural Optimization with Aeroelastic multidisciplinary Constraints on Helicopter Rotor Design written by Peretz P. Friedmann and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent Advances in Multidisciplinary Analysis and Optimization Part 1 written by and published by . This book was released on 1989 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiphysics Simulations in Automotive and Aerospace Applications written by Mojtaba Moatamedi and published by Academic Press. This book was released on 2021-07-20 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiphysics Simulations in Automotive and Aerospace Applications provides the fundamentals and latest developments on numerical methods for solving multiphysics problems, including fluid-solid interaction, fluid-structure-thermal coupling, electromagnetic-fluid-solid coupling, vibro and aeroacoustics. Chapters describe the different algorithms and numerical methods used for solving coupled problems using implicit or explicit coupling problems from industrial or academic applications. Given the book’s comprehensive coverage, automotive and aerospace engineers, designers, graduate students and researchers involved in the simulation of practical coupling problems will find the book useful in its approach. Provides the fundamentals of numerical methods, along with comprehensive examples for solving coupled problems Features multi-physics methods and available codes, along with what those codes can do Presents examples from industrial and academic applications

Download or read book A Multidisciplinary Design Optimization Method Applied to Stoppable Rotor Configurations written by Daniel P. Schrage 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 Rotor Design Optimization Using a Multidisciplinary Approach written by F. K. Straub and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced UAV Aerodynamics Flight Stability and Control written by Pascual Marqués and published by John Wiley & Sons. This book was released on 2017-07-11 with total page 799 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Aerodynamic Shape Optimization Via Control Theory of Helicopter Rotor Blades Using a Non linear Frequency Domain Approach written by Charles A. Tatossian and published by . This book was released on 2008 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multi Objective Memetic Algorithms written by Chi-Keong Goh and published by Springer Science & Business Media. This book was released on 2009-02-26 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of sophisticated evolutionary computing approaches for solving complex problems with multiple conflicting objectives in science and engineering have increased steadily in the recent years. Within this growing trend, Memetic algorithms are, perhaps, one of the most successful stories, having demonstrated better efficacy in dealing with multi-objective problems as compared to its conventional counterparts. Nonetheless, researchers are only beginning to realize the vast potential of multi-objective Memetic algorithm and there remain many open topics in its design. This book presents a very first comprehensive collection of works, written by leading researchers in the field, and reflects the current state-of-the-art in the theory and practice of multi-objective Memetic algorithms. "Multi-Objective Memetic algorithms" is organized for a wide readership and will be a valuable reference for engineers, researchers, senior undergraduates and graduate students who are interested in the areas of Memetic algorithms and multi-objective optimization.

Download or read book An Initiative in Multidisciplinary Optimization of Rotorcraft written by and published by . This book was released on 1988 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Smart Helicopter Rotors written by Ranjan Ganguli and published by Springer. This book was released on 2015-12-16 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exploiting the properties of piezoelectric materials to minimize vibration in rotor-blade actuators, this book demonstrates the potential of smart helicopter rotors to achieve the smoothness of ride associated with jet-engined, fixed-wing aircraft. Vibration control is effected using the concepts of trailing-edge flaps and active-twist. The authors’ optimization-based approach shows the advantage of multiple trailing-edge flaps and algorithms for full-authority control of dual trailing-edge-flap actuators are presented. Hysteresis nonlinearity in piezoelectric stack actuators is highlighted and compensated by use of another algorithm. The idea of response surfaces provides for optimal placement of trailing-edge flaps. The concept of active twist involves the employment of piezoelectrically induced shear actuation in rotating beams. Shear is then demonstrated for a thin-walled aerofoil-section rotor blade under feedback-control vibration minimization. Active twist is shown to be significant in reducing vibration caused by dynamic stall. The exposition of ideas, materials and algorithms in this monograph is supported by extensive reporting of results from numerical simulations of smart helicopter rotors. This monograph will be a valuable source of reference for researchers and engineers with backgrounds in aerospace, mechanical and electrical engineering interested in smart materials and vibration control. 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 Multidisciplinary Optimal Design of a Helicopter Rotor Blade written by Mark C. Reed and published by . This book was released on 1992 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Computational Methods and Design for Greener Aviation written by Tero Tuovinen and published by Springer Nature. This book was released on with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Integration of Dynamic Aerodynamic and Structural Optimization of Helicopter Rotor Blades written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-12-31 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summarized here is the first six years of research into the integration of structural, dynamic, and aerodynamic considerations in the design-optimization process for rotor blades. Specifically discussed here is the application of design optimization techniques for helicopter rotor blades. The reduction of vibratory shears and moments at the blade root, aeroelastic stability of the rotor, optimum airframe design, and an efficient procedure for calculating system sensitivities with respect to the design variables used are discussed. Peters, David A. NASA-CR-189018, NAS 1.26:189018 NAG1-710...

Download or read book Recent Advances in Multidisciplinary Optimization of Rotorcraft written by and published by . This book was released on 1992 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: