Download or read book A Robust and Reliability based Optimization Framework for Conceptual Aircraft Wing Design written by Ricardo Miguel Paiva and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A robustness and reliability based multidisciplinary analysis and optimization framework for aircraft design is presented. Robust design optimization and Reliability Based Design Optimization are merged into a unifed formulation which streamlines the setup of optimization problems and aims at preventing foreseeable implementation issues in uncertainty based design. Surrogate models are evaluated to circumvent the intensive computations resulting from using direct evaluation in nondeterministic optimization. Three types of models are implemented in the framework: quadratic interpolation, regression Kriging and artificial neural networks. Regression Kriging presents the best compromise between performance and accuracy in deterministic wing design problems. The performance of the simultaneous implementation of robustness and reliability is evaluated using simple analytic problems and more complex wing design problems, revealing that performance benefits can still be achieved while satisfying probabilistic constraints rather than the simpler (and not as computationally intensive) robust constraints. The latter are proven to to be unable to follow a reliability constraint as uncertainty in the input variables increases. The computational effort of the reliability analysis is further reduced through the implementation of a coordinate change in the respective optimization sub-problem. The computational tool developed is a stand alone application and it presents a user-friendly graphical user interface. The multidisciplinary analysis and designoptimization tool includes modules for aerodynamics, structural, aeroelastic and cost analysis, that can be used either individually or coupled.

Download or read book A Robust and Reliability Based Optimization Framework for Conceptual Aircraft Wing Design written by Ricardo Miguel Paiva 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 Engineering Optimization 2014 written by Hélder Rodrigues and published by CRC Press. This book was released on 2014-09-26 with total page 1078 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimization methodologies are fundamental instruments to tackle the complexity of today's engineering processes. Engineering Optimization 2014 is dedicated to optimization methods in engineering, and contains the papers presented at the 4th International Conference on Engineering Optimization (ENGOPT2014, Lisbon, Portugal, 8-11 September 2014). The book will be of interest to engineers, applied mathematicians, and computer scientists working on research, development and practical applications of optimization methods in engineering.

Download or read book Knowledge Based Integrated Aircraft Design written by Raghu Chaitanya Munjulury and published by Linköping University Electronic Press. This book was released on 2017-05-23 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design and development of new aircraft are becoming increasingly expensive and timeconsuming. To assist the design process in reducing the development cost, time, and late design changes, the conceptual design needs enhancement using new tools and methods. Integration of several disciplines in the conceptual design as one entity enables to keep the design process intact at every step and obtain a high understanding of the aircraft concepts at early stages. This thesis presents a Knowledge-Based Engineering (KBE) approach and integration of several disciplines in a holistic approach for use in aircraft conceptual design. KBE allows the reuse of obtained aircrafts’ data, information, and knowledge to gain more awareness and a better understanding of the concept under consideration at early stages of design. For this purpose, Knowledge-Based (KB) methodologies are investigated for enhanced geometrical representation and enable variable fidelity tools and Multidisciplinary Design Optimization (MDO). The geometry parameterization techniques are qualitative approaches that produce quantitative results in terms of both robustness and flexibility of the design parameterization. The information/parameters from all tools/disciplines and the design intent of the generated concepts are saved and shared via a central database. The integrated framework facilitates multi-fidelity analysis, combining low-fidelity models with high-fidelity models for a quick estimation, enabling a rapid analysis and enhancing the time for a MDO process. The geometry is further propagated to other disciplines [Computational Fluid Dynamics (CFD), Finite Element Analysis (FEA)] for analysis. This is possible with an automated streamlined process (for CFD, FEM, system simulation) to analyze and increase knowledge early in the design process. Several processes were studied to streamline the geometry for CFD. Two working practices, one for parametric geometry and another for KB geometry are presented for automatic mesh generation. It is observed that analytical methods provide quicker weight estimation of the design and when coupled with KBE provide a better understanding. Integration of 1-D and 3-D models offers the best of both models: faster simulation, and superior geometrical representation. To validate both the framework and concepts generated from the tools, they are implemented in academia in several courses at Linköping University and in industry

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 AeroSandbox written by Peter David Sharpe and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This framework's modular approach to engineering analysis allows sophisticated aerospace problems to be constructed by connecting plug-and-play building blocks in code. This decreases the time required to go from a qualitative vehicle and mission concept to a quantitative, optimized performance estimate. The framework's emphasis on rapid development time and run time enables an engineer to interactively pose design questions, enabling human insight to be more readily applied to the computational design process.

Download or read book Non Deterministic Metamodeling for Multidisciplinary Design Optimization of Aircraft Systems Under Uncertainty written by Daniel L. Clark (Jr.) and published by . This book was released on 2019 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: To make coupled multi-physics-informed design decisions, multidisciplinary analysis, design optimization and uncertainty quantification must be present to accurately represent the full system under investigation. Unfortunately, all of these processes are computationally demanding, requiring a large number of system evaluations with identified uncertain variables, and iterative system evaluations with respect to the design variables of interest. Surrogate or metamodels are used to alleviate the computational burden in both these design exploration activities by trading accuracy with efficiency. The primary objective of this dissertation is to develop a flexible surrogate modeling technique capable of quantifying the uncertainty of multidisciplinary systems in an iterative and efficient procedure.In this work, the Non-Deterministic Kriging (NDK) method is derived. This surrogate model represents a flexible approach for approximating epistemic and aleatory uncertainty. To achieve an iterative and efficient computational framework additional tasks were established: (1) characterize and develop a unified stochastic process incorporating incomplete and mixed uncertainty data; (2) develop a novel adaptive sampling method that effectively and efficiently updates the NDK model to enable a global multidisciplinary design optimization technique under uncertainty; (3) derive analytic sensitivities to achieve non-deterministic sensitivities with respect to the design variables; (4) propose an efficient reliability-based design optimization framework for multidisciplinary systems using NDK to reduce the design space.

Download or read book Engineering Design Reliability Handbook written by Efstratios Nikolaidis and published by CRC Press. This book was released on 2004-12-22 with total page 1216 pages. Available in PDF, EPUB and Kindle. Book excerpt: Researchers in the engineering industry and academia are making important advances on reliability-based design and modeling of uncertainty when data is limited. Non deterministic approaches have enabled industries to save billions by reducing design and warranty costs and by improving quality. Considering the lack of comprehensive and defini

Download or read book Probabilistic Design Optimization of Built up Aircraft Structures with Application written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis discusses a methodology for probabilistic design optimization of aircraft structures subject to a multidisciplinary set of requirements originating from the desire to minimize structural weight while fulfilling the demands for quality, safety, producibility, and affordability. With this design methodology as the framework, a software is developed, which is capable of performing design optimization of metallic built-up beam structures where the material properties, external load, as well as the structural dimensions are treated as probabilistic random variables. The structural and failure analyses are based on analytical and semi-empirical methods whereas the component reliability analysis is based on advanced first-order second moment method. Metrics-based analytical models are used for the manufacturability analysis of individual parts with the total manufacturing cost estimated using models derived from the manufacturing cost / design guide developed by the Battelle's Columbus Laboratories. The resulting optimization problem is solved using the method of sequential quadratic programming. A wing spar design optimization problem is used as a demonstrative example including a comparison between non-buckling and buckling web design concepts. A sensitivity analysis is performed and the optimization results are used to highlight the tradeoffs among weight, reliability, and manufacturing cost.

Download or read book Robust and Reliability based Aeroelastic Design of Composite Wings written by Carl Scarth and published by . This book was released on 2016 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reliability based Design Optimization of Multiphysics Aerospace Systems written by Matthew R. Allen and published by . This book was released on 2004 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of Multi fidelity Aeroelastic Optimization Framework for Flexible Wing Conceptual Design written by Yanxin Huang and published by . This book was released on 2021 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation introduces a framework to carry out the aeroelastic optimization around the steady-state for flexible fixed wings. Such a framework captures geometrical nonlinearities and aerodynamic unsteadiness, which are the challenges in modern aircraft design. This also takes full advantage of structural geometry by integrating multi-fidelity structures with vortex-lattice method (UVLM), allowing effective and accurate multi-stage aircraft design with a variety of aspect ratios. Functions of structural consistency are used to close the gap between multi-stage designs at different fidelity levels. A model update tool is used to ensure structural consistency and allow communications between stages and fidelity levels. In addition, this framework shows its potential to involve more disciplinaries, such as control and stability, by revealing sensitivities with respect to UVLM vorticities and grids.The lower-fidelity aeroelastic model integrates nonlinear strain-based beam elements with UVLM, while the higher-fidelity model integrates nonlinear displacement-based shell elements with UVLM. The resulting aeroelastic models are coupled with a gradient-based method, focusing on overall performance and detailed analysis, respectively. An artificial neural network (ANN) is established for the model update from the lower- to the higher-fidelity structure. It builds a database and performs a statistical approach to address the parameter inequality. Aerodynamic equations are linearized by performing small perturbations and assuming a frozen aerodynamic geometry. The developed UVLM and aeroelastic models are validated by reference models. Analytical aerodynamic sensitivities are verified by the results of finite-difference. In addition, the feasibility of the model update tool is demonstrated by generating a two-dimensional shell and a three-dimensional wing box from original one-dimensional beams. The feasibility of this framework is demonstrated by optimizing a fixed wing under a large upward bending deflection. The impact of different design variables is also observed and discussed. This research illustrates a comprehensive process for an early design of flexible wings. Although the current framework is limited to the incompressible flow and isotropic shell elements, it has the potential to involve more applications with compressibility corrections of UVLM and composite materials.

Download or read book Smart Intelligent Aircraft Structures SARISTU written by Piet Christof Wölcken and published by Springer. This book was released on 2015-09-04 with total page 1025 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book includes the research papers presented in the final conference of the EU funded SARISTU (Smart Intelligent Aircraft Structures) project, held at Moscow, Russia between 19-21 of May 2015. The SARISTU project, which was launched in September 2011, developed and tested a variety of individual applications as well as their combinations. With a strong focus on actual physical integration and subsequent material and structural testing, SARISTU has been responsible for important progress on the route to industrialization of structure integrated functionalities such as Conformal Morphing, Structural Health Monitoring and Nanocomposites. The gap- and edge-free deformation of aerodynamic surfaces known as conformal morphing has gained previously unrealized capabilities such as inherent de-icing, erosion protection and lightning strike protection, while at the same time the technological risk has been greatly reduced. Individual structural health monitoring techniques can now be applied at the part-manufacturing level rather than via extending an aircraft’s time in the final assembly line. And nanocomposites no longer lose their improved properties when trying to upscale from neat resin testing to full laminate testing at element level. As such, this book familiarizes the reader with the most significant develo pments, achievements and key technological steps which have been made possible through the four-year long cooperation of 64 leading entities from 16 different countries with the financial support of the European Commission.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optimization of Aircraft Tow Steered Composite Wing Structures written by Michael Chamberlain Henson and published by . This book was released on 2017 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: An efficient methodology for design of aircraft composite wing structures is presented. The developed approach provides a flexible and integrated strategy to leverage advantages of composite material tow steering to achieve more effective wing designs. This is accomplished by including the coupling between OML geometry, aerodynamics and structural response. Structural and aerodynamic analyses are derived from parametric aircraft geometry and assembled into a framework for aero-structural wing sizing. A Ritz equivalent plate solution is extended to model composite materials with variable fiber path geometry. The structural modeling approach is implemented to automate creation of both Ritz and finite element analyses. The Ritz structural model is coupled to a vortex lattice flow solver and implemented into an optimization framework. By using this approach we are more rapidly able to gain an understanding of optimal wing skin laminates that satisfy a variety of constrains and objective functions. The framework is suitable for conceptual and preliminary design of aircraft wing skins and it has been applied to accomplish a tow-steered wing skin design.

Download or read book Robust Design Methodology for Reliability written by Bo Bergman and published by John Wiley & Sons. This book was released on 2009-08-18 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on deep theoretical as well as practical experience in Reliability and Quality Sciences, Robust Design Methodology for Reliability constructively addresses practical reliability problems. It offers a comprehensive design theory for reliability, utilizing robust design methodology and six sigma frameworks. In particular, the relation between un-reliability and variation and uncertainty is explored and reliability improvement measures in early product development stages are suggested. Many companies today utilise design for Six Sigma (DfSS) for strategic improvement of the design process, but often without explicitly describing the reliability perspective; this book explains how reliability design can relate to and work with DfSS and illustrates this with real–world problems. The contributors advocate designing for robustness, i.e. insensitivity to variation in the early stages of product design development. Methods for rational treatment of uncertainties in model assumptions are also presented. This book promotes a new approach to reliability thinking that addresses the design process and proneness to failure in the design phase via sensitivity to variation and uncertainty; includes contributions from both academics and industry practitioners with a broad scope of expertise, including quality science, mathematical statistics and reliability engineering; takes the innovative approach of promoting the study of variation and uncertainty as a basis for reliability work; includes case studies and illustrative examples that translate the theory into practice. Robust Design Methodology for Reliability provides a starting point for new thinking in practical reliability improvement work that will appeal to advanced designers and reliability specialists in academia and industry including fatigue engineers, product development and process/ quality professionals, especially those interested in and/ or using the DfSS framework.

Download or read book Conceptual Design and Optimization Methodology for Box Wing Aircraft written by Paul Olugbeji Jemitola and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A conceptual design optimization methodology was developed for a medium range box wing aircraft. A baseline conventional cantilever wing aircraft designed for the same mis- sion and payload was also optimized alongside a baseline box wing aircraft. An empirical formula for the mass estimation of the fore and aft wings of the box wing aircraft was derived by relating conventional cantilever wings to box wing aircraft wings. The results indicate that the fore and aft wings would use the same correction coe cient and that the aft wing would be lighter than the fore wing on the medium range box wing aircraft because of reduced sweep. As part of the methodology, a computational study was performed to analyze di erent wing/tip n xities using a statically loaded idealized box wing con guration. The analy- ses determined the best joint xity by comparing the stress distributions in nite element torsion box models in addition to aerodynamic requirements. The analyses indicates that the rigid joint is the most suitable. Studies were also performed to investigate the structural implications of changing only the tip n inclinations on the box wing aircraft. Tip n inclination refers to the angle the tip n makes to the vertical body axis of the aircraft. No signi cant variations in wing structural design drivers as a function of tip n inclination were observed. Stochastic and deterministic optimization routines were performed on the baseline box wing aircraft using the methodology developed where the variables were wing area, av- erage thickness to chord ratio and sweep angle. The conventional aircraft design showed similar performance and characteristics to the equivalent in-service aircraft thereby pro- viding some validation to the methodology and the results for the box wing aircraft. Longitudinal stability investigations showed that the extra fuel capacity of the box wing in the ns could be used to reduce trim drag. The short period oscillation of the conventional cantilever wing aircraft was found to be satisfactory but the box wing aircraft was found to be unacceptable hence requiring stability augmentation systems. The eld and ight performance of the box wing showed to be better than the conventional cantilever wing aircraft. Overall, the economic advantages of the box wing aircraft over the conventional cantilever wing aircraft improve with increase in fuel price making the box wing a worthy replacement for the conventional cantilever wing aircraft.