Download or read book Probabilistic Design of Damage Tolerant Composite Aircraft Structures written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reliability based Methods Applied to the Design of Damage Tolerant Aircraft Structures written by David Timothy Rusk and published by . This book was released on 2000 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book USAF Damage Tolerant Design Handbook written by and published by . This book was released on 1984 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Composite Structures Design Safety and Innovation written by Dr. Bjorn F. Backman and published by Elsevier. This book was released on 2005-06-09 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerospace structural design, especially for large aircraft, is an empirical pursuit dominated by rules of thumb and often-painful service experiences. Expertise on traditional materials is not transferable to “new materials, processes and structural concepts. This is because it is not based on or derived from well-defined measures of safety. This book addresses the need for safe innovation based on practical, explicit structural safety constraints for use in innovative structures of the future where guiding service experience is non-existent. The book covers new ground by the demonstration of ways to satisfy levels of safety by focusing on structural integrity; and complementing the lack of service experience with risk management, based on flexible inspection methods recognizing that safety is a function of time. Fundamentally the book shoes demonstrates how safety methods can be made available to the engineering community without requiring huge statistical databases to establish internal and external loads distributions for use in reliability analysis. An essential title for anyone working on structural integrity, or composite structures. It will be of equal interest to aerospace engineers and materials scientists working in academia, industry and government. Demonstrates a practically manageable way to produce safe innovation using composites in environments with no service experience New approach to a subject that has not previously been treated in a holistic manner This book could not have come at a more topical time, Boeing are currently launching the first commercial plane made entirely of composite materials The focus of this book is Composite Materials but other fields of innovation could be treated in the same manner
Download or read book Estimation of Probability of Failure for Damage Tolerant Aerospace Structures written by Keith Halbert and published by . This book was released on 2014 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The majority of aircraft structures are designed to be damage-tolerant such that safe operation can continue in the presence of minor damage. It is necessary to schedule inspections so that minor damage can be found and repaired. It is generally not possible to perform structural inspections prior to every flight. The scheduling is traditionally accomplished through a deterministic set of methods referred to as Damage Tolerance Analysis (DTA). DTA has proven to produce safe aircraft but does not provide estimates of the probability of failure of future flights or the probability of repair of future inspections. Without these estimates maintenance costs cannot be accurately predicted. Also, estimation of failure probabilities is now a regulatory requirement for some aircraft. The set of methods concerned with the probabilistic formulation of this problem are collectively referred to as Probabilistic Damage Tolerance Analysis (PDTA). The goal of PDTA is to control the failure probability while holding maintenance costs to a reasonable level. This work focuses specifically on PDTA for fatigue cracking of metallic aircraft structures. The growth of a crack (or cracks) must be modeled using all available data and engineering knowledge. The length of a crack can be assessed only indirectly through evidence such as non-destructive inspection results, failures or lack of failures, and the observed severity of usage of the structure. The current set of industry PDTA tools are lacking in several ways: they may in some cases yield poor estimates of failure probabilities, they cannot realistically represent the variety of possible failure and maintenance scenarios, and they do not allow for model updates which incorporate observed evidence. A PDTA modeling methodology must be flexible enough to estimate accurately the failure and repair probabilities under a variety of maintenance scenarios, and be capable of incorporating observed evidence as it becomes available. This dissertation describes and develops new PDTA methodologies that directly address the deficiencies of the currently used tools. The new methods are implemented as a free, publicly licensed and open source R software package that can be downloaded from the Comprehensive R Archive Network. The tools consist of two main components. First, an explicit (and expensive) Monte Carlo approach is presented which simulates the life of an aircraft structural component flight-by-flight. This straightforward MC routine can be used to provide defensible estimates of the failure probabilities for future flights and repair probabilities for future inspections under a variety of failure and maintenance scenarios. This routine is intended to provide baseline estimates against which to compare the results of other, more efficient approaches. Second, an original approach is described which models the fatigue process and future scheduled inspections as a hidden Markov model. This model is solved using a particle-based approximation and the sequential importance sampling algorithm, which provides an efficient solution to the PDTA problem. Sequential importance sampling is an extension of importance sampling to a Markov process, allowing for efficient Bayesian updating of model parameters. This model updating capability, the benefit of which is demonstrated, is lacking in other PDTA approaches. The results of this approach are shown to agree with the results of the explicit Monte Carlo routine for a number of PDTA problems. Extensions to the typical PDTA problem, which cannot be solved using currently available tools, are presented and solved in this work. These extensions include incorporating observed evidence (such as non-destructive inspection results), more realistic treatment of possible future repairs, and the modeling of failure involving more than one crack (the so-called continuing damage problem). The described hidden Markov model / sequential importance sampling approach to PDTA has the potential to improve aerospace structural safety and reduce maintenance costs by providing a more accurate assessment of the risk of failure and the likelihood of repairs throughout the life of an aircraft.
Download or read book USAF Damage Tolerant Design Handbook written by and published by . This book was released on 1984 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural Design Methodology Based on Concepts of Uncertainty written by K. Y. Lin and published by . This book was released on 2000 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this report, an approach to damage-tolerant aircraft structural design is proposed based on the concept of an equivalent "Level of Safety" that incorporates past service experience in the design of new structures. The discrete "Level of Safety" for a single inspection event is defined as the compliment of the probability that a single flaw size larger than the critical flaw size for residual strength of the structure exists, and that the flaw will not be detected. The cumulative 'Level of Safety" for the entire structure is the product of the discrete "Level of Safety" values for each flaw of each damage type present at each location in the structure. Based on the definition of "Level of Safety", a design procedure was identified and demonstrated on a composite sandwich panel for various damage types, with results showing the sensitivity of the structural sizing parameters to the relative safety of the design. The "Level of Safety" approach has broad potential application to damage-tolerant aircraft sturctural design with uncertainty.
Download or read book Probabilistic Damage Tolerance Analysis of Aircraft Structures written by Björn Palmberg and published by . This book was released on 1985 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling the Effect of Damage in Composite Structures written by Christos Kassapoglou and published by John Wiley & Sons. This book was released on 2015-03-11 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensively covers new and existing methods for the design and analysis of composites structures with damage present Provides efficient and accurate approaches for analysing structures with holes and impact damage Introduces a new methodology for fatigue analysis of composites Provides design guidelines, and step by step descriptions of how to apply the methods, along with evaluation of their accuracy and applicability Includes problems and exercises Accompanied by a website hosting lecture slides and solutions
Download or read book Advanced Durability and Damage Tolerance Design and Analysis Methods for Composite Structures Lessons Learned from NASA Technology Development Programs written by Charles E. Harris and published by . This book was released on 2003 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Damage Tolerance of Metallic Aircraft Structures written by Sérgio M. O. Tavares and published by Springer. This book was released on 2018-08-06 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a state-of-the-art review of the fail-safe and damage tolerance approaches, allowing weight savings and increasing aircraft reliability and structural integrity. The application of the damage tolerance approach requires extensive know-how of the fatigue and fracture properties, corrosion strength, potential failure modes and non-destructive inspection techniques, particularly minimum detectable defect and inspection intervals. In parallel, engineering practice involving damage tolerance requires numerical techniques for stress analysis of cracked structures. These evolved from basic mode I evaluations using rough finite element approaches, to current 3D modeling based on energetic approaches as the VCCT, or simulation of joining processes. This book provides a concise introduction to this subject.
Download or read book Damage Tolerance in Aircraft Structures written by M. S. Rosenfeld and published by ASTM International. This book was released on 1971-03 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Damage Tolerance in Aircraft Structures written by American Society for Testing and Materials and published by ASTM International. This book was released on 1971 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Damage Tolerance in Advanced Composites written by Golam Newaz and published by Routledge. This book was released on 2018-12-13 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: This recent book provides a detailed presentation of damage tolerance assessment and characterization methods for advanced composites, as well as an examination of the role of damage tolerance in the design of composites. Included are analytical models for different types of damage in different composite materials. Tables provide helpful reference
Download or read book Design of Composite Structures for Reliability and Damage Tolerance written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-25 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: A summary of research conducted during the first year is presented. The research objectives were sought by conducting two tasks: (1) investigation of probabilistic design techniques for reliability-based design of composite sandwich panels, and (2) examination of strain energy density failure criterion in conjunction with response surface methodology for global-local design of damage tolerant helicopter fuselage structures. This report primarily discusses the efforts surrounding the first task and provides a discussion of some preliminary work involving the second task. Rais-Rohani, Masoud Langley Research Center
Download or read book Development of Probabilistic Design Methodology for Composite Structures written by P. M. Gary and published by . This book was released on 1997 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: This program was conducted by Vought Aircraft Company, Dallas, Texas, to perform technical studies to aid in the development of a probabilistic design methodology. The foundation of the probabilistic design approach, applied to composite structure, is to base design criteria and objectives on reliability targets instead of factors of safety. Control of the process, in terms of how much it differs from the traditional approach, is maintained by the "Probability of Structural Failure." The key technical issues addressed in this contract were the overall assessment of the accuracy of the methodology, current reliability experience, definition of appropriate goals, and database development. The overall assessment of the accuracy of the methodology was done by reviewing current published documents and papers in the probabilistic design field. This review focused on similarities and differences between approaches. The database development was done by visiting airline maintenance depots and naval aviation depots to collect data on structural failures. The analyses of such data produced historical values for aircraft structural reliability. Current structural reliability issues and reliability goals were addressed by analyzing the wing box of the Lear Fan aircraft using Vought's Probabilistic Design Model. Measures of structural reliability such as single flight hour probability of failure for the whole wing box, including upper skin, lower skin, and substructure were produced.
Download or read book Analysis and Support Initiative for Structural Technology ASIST written by Peggy C. Miedlar and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
