Aeronautical engineering: A continuing bibliography with indexes (supplement 282)

This bibliography lists 623 reports, articles, and other documents introduced into the NASA scientific and technical information system in Aug. 1992. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles

Enabling an ageing workforce: Using design to innovate the workplace and empower older workers

Australia’s population is ageing, but with enhanced health prospects and insufficient retirement funds, and industries impacted by a dwindling itinerate manual labour supply, workers will want, and may need, to remain in the workforce for longer. However, as people age, they lose muscular strength, experience a decline in physical and cognitive performance, and are more vulnerable to muscular-skeletal issues caused by repetitive or awkward movement patterns. Consequently, ageing workers in occupations that require sustained physical activities are at increased risk of injury and exacerbated physical decline and may experience ageist discrimination in the workplace that impacts their psychological wellbeing. This research, Enabling an Ageing Workforce, recognises the issues facing the older worker across a range of different workplace contexts and asks the question: How can design and new technologies address the compounding factors of an ageing (working) population and enable older workers to continue to be productive and effective whilst ensuring their personal wellbeing? Enabling an Ageing Workforce’ is a collaborative research and design project between RMIT University’s ‘Safeness by Design’ initiative and the Innovation Centre of WorkSafe Victoria. This project investigates ageing, wellbeing, and workplace safeness within specific industries to identify areas of concern, opportunities for design intervention, and the proposal of future-focused design solutions. The researchers conduct a substantial scope of enquiry, while concurrently undertaking a partnered design studio with Industrial Design students, to develop and respond with appropriate design solutions. The research identifies that safeness issues exist across specific industry contexts because of workplace culture, practices and predominant behaviours, specific work actions and activities, workplace design, economic and time pressures, and poor risk literacy, training and awareness. The design studio component sees students addressing research-identified issues across many industry sectors and workplace contexts to: • prevent musculoskeletal issues in healthcare workers in the homecare environment, • correct harmful movement behaviours in manufacturing environments, • support older workers in manual tasks, through assistive technologies, • address mental health in the construction industry, • reduce ladder injuries in the residential construction industry, • reduce vibration related injuries in the agricultural sector. This research reveals insights into how a ‘safeness by design’ lens can enable an ageing Australian workforce. Such an approach needs to balance pre-emptive and reactive safety measures, focusing on creating a safe and supportive working environment for all workers. Whilst it is important to support older workers to reduce risk or injury and to promote their capability and performance, enabling longevity, it is also critical to implement measures that protect younger workers from unsafe workplace behaviours, processes and expectations that can lead to longer-term impairment, and may result in them leaving that industry prematurely

Aeronautical engineering: A special bibliography with indexes, supplement 80

This bibliography lists 277 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1977

The 1992 Research/Technology report

The 1992 Research & Technology report is organized so that a broad cross section of the community can readily use it. A short introductory paragraph begins each article and will prove to be an invaluable reference tool for the layperson. The approximately 200 articles summarize the progress made during the year in various technical areas and portray the technical and administrative support associated with Lewis technology programs

Développement des méthodes d’ingénierie pour la spécification et la quantification du bruit structurel SBN dans les cabines des hélicoptères

La prédiction du comportement vibroacoustique à l’intérieur d’une cabine d’hélicoptère nécessite la modélisation vibroacoustique de l’ensemble de la boite de transmission principale, toit et fuselage. Ce projet a pour objectif de développer et mettre en place une méthode hybride au profit des constructeurs d’hélicoptères pour leur permettre de prédire le bruit solidien à l’intérieur de la cabine, hors les conditions de fonctionnement d’origine de l’hélicoptère. Le but est de pouvoir caractériser les forces injectées dans le toit de l’hélicoptère à la suite du fonctionnement de la boite de transmission principale, quantifier le bruit solidien rayonné à l’intérieur de la cabine, identifier les chemins de transfert dominants, et mettre en place des solutions de conception pour réduire la transmission solidienne de vibrations mécaniques et par la suite diminuer la transmission acoustique du bruit dans la cabine. Les méthodes développées et utilisées sont basées sur les techniques d’analyse des chemins de transfert et de la sous-structuration dynamique, en prenant en compte plusieurs paramètres qui peuvent influencer la qualité des résultats.La réduction des nuisances sonores dans les hélicoptères constitue un élément compétitif dans le marché, et une préoccupation pour la santé de l’équipage. La prédiction du comportement vibroacoustiques à l’intérieur de la cabine nécessite la modélisation vibroacoustique de l’ensemble de la boite de transmission principale, toit et fuselage pour comprendre les phénomènes de transmission vibroacoustique à travers ces sous-systèmes. Ce projet a pour objectif de développer et mettre en place une méthode hybride au profit des constructeurs d’hélicoptères pour leur permettre de prédire le bruit solidien SBN à l’intérieur de la cabine, sans avoir besoin d'opérer l’hélicoptère dans des conditions réelles. Pour cela, il faut caractériser les forces injectées sur le toit de l’hélicoptère, quantifier le bruit solidien rayonné à l’intérieur de la cabine, identifier les chemins de transfert dominants, et mettre en place des solutions de conception pour réduire la transmission solidienne de vibrations mécaniques et par la suite diminuer la transmission acoustique du bruit dans la cabine. Plusieurs études numériques et expérimentales ont été réalisées sur des systèmes académiques représentatifs d’hélicoptère et systèmes réels. Les méthodes développées et utilisées sont basées sur les techniques d’analyse des chemins de transfert et de la sous-structuration dynamique, en considérant plusieurs paramètres, comme le couplage vs le découplage, l’utilisation des matrices de sous-mobilité à la place d’une mobilité globale, le nombre des points indicateurs pour déterminer les forces équivalentes, la méthode d’inversion, et le nombre des degrés de liberté choisis. Une première partie de cette thèse porte sur la caractérisation expérimentale d’un isolateur vibratoire utilisé dans les avions. Une méthode inverse hybride expérimentale a été développée pour permettre sa caractérisation sur un banc d’essai dans le laboratoire, pour mesurer les forces transmises aux structures connectées. La deuxième partie concerne une étude numérique effectuée sur un système représentatif d’un hélicoptère. Les mesures réalisées en utilisant les méthodes d’intérêts (TPA et CB-TPA), ont pour but d’investiguer leurs applicabilités sur le système et vérifier la qualité des résultats. La troisième partie est dédiée aux mesures expérimentales effectuées dans le laboratoire sur le système académique représentatif d’un hélicoptère, pour mettre en application les méthodes utilisées, et vérifier les résultats obtenus. La dernière partie est réservée aux études expérimentales réalisées sur un hélicoptère Bell 407. À partir des propriétés mécaniques des sous-systèmes, les méthodes permettent de prédire le comportement vibroacoustique à l’intérieur de la cabine. La contribution des chemins de transfert dominants est étudiée, et les résultats montrent que les méthodes proposées sont capables de prédire le bruit solidien, permettant aux constructeurs d’hélicoptères de partager le travail entre plusieurs équipes pour réduire le temps des mesures, et accélérer le processus de correction avant la phase de l’assemblage final, ce qui permet sans doute de réduire le niveau de bruit rayonné dans la cabine.Abstract : The reduction of noise in helicopters is a competitive element in the market, and a concern for the health of the crew. The prediction of the vibroacoustic behavior inside the cabin requires the vibroacoustic modeling of the entire main gearbox, roof, and fuselage to understand the vibroacoustic transmission phenomena through these subsystems. The objective of this project is to develop and implement a hybrid method for the benefit of helicopter manufacturers to enable them to predict structure-borne-noise SBN inside the cabin, without having to operate the helicopter in real conditions. To do so, it is necessary to characterize the forces injected on the helicopter roof, to quantify the radiated structure-borne-noise inside the cabin, to identify the dominant transfer paths, and to implement design solutions to reduce the structure-borne transmission of mechanical vibrations and subsequently reduce the acoustic transmission of noise in the cabin. Several numerical and experimental studies have been performed on representative academic helicopter systems and real systems. The methods developed and used are based on the transfer paths analysis techniques and dynamic substructuring, considering several parameters, such as the coupling vs. the decoupling, the use of sub-mobility matrices instead of a global mobility, the number of indicator points to determine the equivalent forces, the inversion methods, and the number of degrees of freedom chosen. The first part of this thesis deals with the experimental characterization of an aircraft noise abatement isolator. An experimental hybrid inverse method has been developed to allow its characterization on a test bench in the laboratory, to measure the forces transmitted to the connected structures. The second part concerns a numerical study performed on a representative system of a helicopter. The measurements carried out using the methods of interest (TPA and CB-TPA), aim to investigate their applicability to the system and verify the quality of the results. The third part is dedicated to the experimental measurements carried out in the laboratory on the representative academic system of a helicopter, to apply the methods used, and to verify the results obtained. The last part is reserved for the experimental studies carried out on a Bell 407 helicopter. From the mechanical properties of the subsystems, the methods allow them to predict the vibroacoustic behavior inside the cabin. The contribution of the dominant transfer paths is studied, and the results show that the proposed methods can predict structure-borne-noise, allowing the helicopter manufacturers to share the work between several teams to reduce measurement time, and speed up the process of correction before the final assembly phase, which undoubtedly reduces the level of noise radiated into the cabin

Sensors Fault Diagnosis Trends and Applications

Fault diagnosis has always been a concern for industry. In general, diagnosis in complex systems requires the acquisition of information from sensors and the processing and extracting of required features for the classification or identification of faults. Therefore, fault diagnosis of sensors is clearly important as faulty information from a sensor may lead to misleading conclusions about the whole system. As engineering systems grow in size and complexity, it becomes more and more important to diagnose faulty behavior before it can lead to total failure. In the light of above issues, this book is dedicated to trends and applications in modern-sensor fault diagnosis

Bibliography of Lewis Research Center technical publications announced in 1989

This compilation of abstracts describes and indexes the technical reporting that resulted from the scientific and engineering work performed and managed by the Lewis Research Center in 1989. All the publications were announced in the 1989 issues of STAR (Scientific and Technical Aerospace Reports) and/or IAA (International Aerospace Abstracts). Included are research reports, journal articles, conference presentations, patents and patent applications, and theses

Research and Technology 1995

This report selectively summarizes the NASA Lewis Research Center's research and technology accomplishments for fiscal year 1995. It comprises over 150 short articles submitted by the staff members of the technical directorates. The report is organized into six major sections: aeronautics, aerospace technology, space flight systems, engineering support, Lewis Research Academy, and technology transfer. A table of contents, an author index, and a list of NASA Headquarters program offices have been included to assist the reader in finding articles of special interest. This report is not intended to be a comprehensive summary of all research and technology work done over the past fiscal year. Most of the work is reported in Lewis-published technical reports, journal articles, and presentations prepared by Lewis staff members and contractors (for abstracts of these Lewis-authored reports, visit the Lewis Technical Report Server (LETRS) on the World Wide Web-http://letrs.lerc.nasa.gov/LeTRS/). In addition, university grants have enabled faculty members and graduate students to engage in sponsored research that is reported at technical meetings or in journal articles. For each article in this report, a Lewis contact person has been identified, and where possible, reference documents are listed so that additional information can be easily obtained. The diversity of topics attests to the breadth of research and technology being pursued and to the skill mix of the staff that makes it possible. For more information about Lewis' research, visit us on the World Wide web-http://www.lerc.nasa.gov