Author: Mustafa Kubilay IctuzerPublisher:
ISBN:
Category : Aerofoils
Languages : en
Pages : 118
Book Description
Multi-element Airfoil Optimization Using Computational Fluid Dynamics
Author: Mustafa Kubilay IctuzerPublisher:
ISBN:
Category : Aerofoils
Languages : en
Pages : 118
Book Description
Optimization of Multi-Element Airfoils
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 75
Book Description
A review of techniques aimed at maximizing C1/Cd and C1 for multi- element airfoils showed the need for more exhaustive testing of possible configurations of flap deflection, slot geometry and airfoil angle of attack. For a typical 4-element airfoil, the number of possible configurations can easily be in the billions. A new technique, based on evolution strategy, has been developed for the problem of optimizing a multi-element airfoil with respect to its envelope of maximum C1/Cd versus C1. This technique was applied to an airfoil having a slotted leading edge flap and a double-slotted trailing edge flap using an existing computer program for 2D subsonic multi-element airfoils to provide values of aerodynamic coefficients. Although limitations of the program precluded the full determination of the envelope of C1/Cd vs C1 the problem of maximizing C1/Cd for a minimum C1 constraint was solved. The result of testing approximately 400 configurations generated by the random mutation- natural selection procedure of evolution strategy was an 8-fold increase in C1/ Cd iwth a 12% increase in C1 over the initial geometry.
Output-based Adaptive RANS Solutions Using Higher-order FEM on a Multi-element Airfoil
Author: Carmen-Ioana UrsachiPublisher:
ISBN:
Category :
Languages : en
Pages : 87
Book Description
Higher-order methods in computational fluid dynamics have the potential to provide accurate solutions at lower computational costs than traditional methods. Obtaining accurate flow solutions requires the use of computational meshes that resolve relevant solution features, but generating such meshes a priori is difficult. In this thesis, the effects of adaptivity and discretization order are studied on the solutions of a 2D multi-element high-lift airfoil test case. The flow in this test case is simulated by the RANS equations and Spalart-Allmaras turbulence model. Numerical flow solutions are obtained using both stabilized continuous Galerkin and discontinuous Galerkin finite element frameworks. For both discretizations, a series of increasingly refined adapted meshes are generated using the Metric Optimization via Error Sampling and Synthesis algorithm. The convergence of aerodynamic coefficients, surface pressure, and skin friction on these meshes are studied in order to evaluate the accuracy and cost of the solution. This study is done for several discretization orders, and for both linear and curved meshes. In addition, the characteristics of the adapted meshes for different discretization orders are investigated at a prescribed error level. This analysis provides insight into how the discretization order affects the mesh, along with the resulting solution accuracy and cost. The conclusions of this study indicate that higher-order methods, in particular the p = 2 and p = 3 Continuous Galerkin Variational Multi-Scale with Discontinuous subscales discretizations, provide accurate outputs with an order of magnitude less computational time than p = 1 methods.
Simulation-driven Aerodynamic Design Using Variable-fidelity Models
Author: Leifur LeifssonPublisher: World Scientific
ISBN: 1783266309
Category : Technology & Engineering
Languages : en
Pages : 444
Book Description
Computer simulations is a fundamental tool of the design process in many engineering disciplines including aerospace engineering. However, although high-fidelity numerical models are accurate, they can be computationally expensive with evaluation time for a single design as long as hours, days or even weeks. Simulation-driven design using conventional optimization techniques may be therefore prohibitive.This book explores the alternative: performing computationally efficient design using surrogate-based optimization, where the high-fidelity model is replaced by its computationally cheap but still reasonably accurate representation: a surrogate. The emphasis is on physics-based surrogates. Application-wise, the focus is on aerodynamics and the methods and techniques described in the book are demonstrated using aerodynamic shape optimization cases. Applications in other engineering fields are also demonstrated.State-of-the-art techniques and a depth of coverage never published before make this a unique and essential book for all researchers working in aerospace and other engineering areas and dealing with optimization, computationally expensive design problems, and simulation-driven design.
Computational Fluid Dynamics 2002
Author: Steve ArmfieldPublisher: Springer Science & Business Media
ISBN: 3642593348
Category : Science
Languages : en
Pages : 837
Book Description
We are pleased to present the Proceedings of the Second International Conference on Computational Fluid Dynamics held at the University of Sydney, Australia, from July 15 to 19, 2002. The conference was a productive meeting of scientists, mathematicians and engineers involved in the computation of fluid flow. Keynote lectures were presented in the areas of optimisation, algorithms, turbulence and bio-fluid mechanics. Two hundred and fifty abstracts from many countries were received for con sideration. The executive committee, consisting of A. Lerat, M. Napolitano, J.J. Chattot, N. Satofuka and myself, were responsible for the selection of papers. Each of the members had a separate subcommittee to carry out the evaluation. One hundred and seventy papers were selected of which one hundred and fifty two were presented at the conference. All papers that appear in the proceedings have been peer reviewed by a panel of experts (with a minimum of two for every paper) before publication. The conference was attended by 160 delegates with a minimum of late with drawals. The informal and friendly atmosphere provided by the university sur roundings was highly appreciated, and the technical aspects of the conference were stimulating. It is appropriate here to thank Alain Lerat, the retiring secretary of the international scientific committee of the conference. We also wish to welcome J. J. Chattot who is the incoming secretary.
Advanced Computational Fluid and Aerodynamics
Author: Paul G. TuckerPublisher: Cambridge University Press
ISBN: 131666659X
Category : Technology & Engineering
Languages : en
Pages : 589
Book Description
The advent of supercomputers has brought computational fluid dynamics (CFD) to the forefront as a tool to analyze increasingly complex simulation scenarios in many fields. Computational aerodynamics problems are also increasingly moving towards being coupled, multi-physics and multi-scale with complex, moving geometries. The latter presents severe geometry handling and meshing challenges. Simulations also frequently use formal design optimization processes. This book explains the evolution of CFD and provides a comprehensive overview of the plethora of tools and methods available for solving complex scenarios while exploring the future directions and possible outcomes. Using numerous examples, illustrations and computational methods the author discusses turbulence modeling, pre and post processing, coupled solutions, the importance of design optimization, multiphysics problems, reduced order models, and large scale computations and the future of CFD. Advanced Computational Fluid and Aerodynamics is suitable for audiences engaged in computational fluid dynamics including advanced undergraduates, researchers and industrial practitioners.
Two-dimensional High-lift Aerodynamic Optimization Using Neural Networks
Author: Roxana M. GreenmanRecent Development of Aerodynamic Design Methodologies
Author: Kozo FujiiPublisher: Springer Science & Business Media
ISBN: 3322899527
Category : Technology & Engineering
Languages : en
Pages : 228
Book Description
Computational Fluid Dynamics (CFD) has made remarkable progress in the last two decades and is becoming an important, if not inevitable, analytical tool for both fundamental and practical fluid dynamics research. The analysis of flow fields is important in the sense that it improves the researcher's understanding of the flow features. CFD analysis also indirectly helps the design of new aircraft and/or spacecraft. However, design methodologies are the real need for the development of aircraft or spacecraft. They directly contribute to the design process and can significantly shorten the design cycle. Although quite a few publications have been written on this subject, most of the methods proposed were not used in practice in the past due to an immature research level and restrictions due to the inadequate computing capabilities. With the progress of high-speed computers, the time has come for such methods to be used practically. There is strong evidence of a growing interest in the development and use of aerodynamic inverse design and optimization techniques. This is true, not only for aerospace industries, but also for any industries requiring fluid dynamic design. This clearly shows the matured engineering need for optimum aerodynamic shape design methodologies. Therefore, it seems timely to publish a book in which eminent researchers in this area can elaborate on their research efforts and discuss it in conjunction with other efforts.
Parallel Computational Fluid Dynamics '99
Author: D. KeyesPublisher: Elsevier
ISBN: 008053838X
Category : Mathematics
Languages : en
Pages : 477
Book Description
Contributed presentations were given by over 50 researchers representing the state of parallel CFD art and architecture from Asia, Europe, and North America. Major developments at the 1999 meeting were: (1) the effective use of as many as 2048 processors in implicit computations in CFD, (2) the acceptance that parallelism is now the 'easy part' of large-scale CFD compared to the difficulty of getting good per-node performance on the latest fast-clocked commodity processors with cache-based memory systems, (3) favorable prospects for Lattice-Boltzmann computations in CFD (especially for problems that Eulerian and even Lagrangian techniques do not handle well, such as two-phase flows and flows with exceedingly multiple-connected demains with a lot of holes in them, but even for conventional flows already handled well with the continuum-based approaches of PDEs), and (4) the nascent integration of optimization and very large-scale CFD. Further details of Parallel CFD'99, as well as other conferences in this series, are available at http://www.parcfd.org
Optimization and Computational Fluid Dynamics
Author: Dominique ThéveninPublisher: Springer Science & Business Media
ISBN: 3540721533
Category : Technology & Engineering
Languages : en
Pages : 301
Book Description
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.