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Design of a Scaled Flight Test Vehicle Including Linear Aeroelastic EffectsEger, Charles Alfred Gaitan 23 May 2013 (has links)
A procedure for the design of a scaled aircraft using linear aeroelastic scaling is developed and demonstrated. Previous work has shown the viability in matching scaled structural frequencies and mode shapes in order to achieve consistent linear scaling of simple models. This methodology is adopted for use on a high fidelity joined-wing aircraft model. Natural frequencies and mode shapes are matched by optimizing structural ply properties and nonstructural mass. A full-scale SensorCraft concept developed by AFRL and Boeing serves as the target model, and a 1/9th span geometrically scaled remotely piloted vehicle (RPV) serves as the initial design point. The aeroelastic response of the final design is verified against the response of the full-scale model. Reasonable agreement is seen in both aeroelastic damping and frequency for a range of flight velocities, but some discrepancy remains in accurately capturing the flutter velocity. / Master of Science
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AERODYNAMIC ANALYSIS OF THE JOINED-WING CONFIGURATION OF A HIGH-ALTITUDE, LONG ENDURANCE (HALE) AIRCRAFTSIVAJI, RANGARAJAN 01 July 2004 (has links)
No description available.
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Failure load of joined zirconium dioxide componentsAlqarawi, Firas Khalid 28 September 2016 (has links)
STATEMENT OF PROBLEM. Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramic material has been reported to possess remarkably high flexural strength; however, after sintering zirconium dioxide (ZrO2) frameworks and fixed partial dentures, some may not fit properly when trying them on their master cast.
PURPOSE. The objective of this study was to investigate joining fully sintered YTZ-P by various methods including adhesive cements or fusion with intervening materials.
MATERIALS AND METHODS. 216 specimens were used in this study; bars were fabricated from Vita In-Ceram YZ blocks and three bars were joined using dental cements; RelyX Unicem 2 Clicker and Multilink Automix, or fusing them with VM9, Infusion Glass, Boron Oxide, Aluminum Oxide, LUDOX, Colloidal Zirconia and Mullite Zirconia. The load to failure in Newtons was determined using a 3-point bending test.
RESULTS. Sandblasted bars for RelyX (64.38N, RelyX-A-Sb) and Multilink (48.58N, M-Sb) wasn’t significantly higher compared to as-sintered groups (45.87N, RelyX-A) and (34.69N, M-A). Coating the bars with Monobond-Plus had a significantly higher load to failure 123.22N, RelyX-A-MP and 136.06N, M-MP compared to as-sintered and sandblasted groups. VM9 at an end firing temperature (EFT) of 1200 °C was significantly higher (228.97N, V-5) compared to lower fusing temperatures. Glass at an end firing temperature of 1200 °C was significantly higher (460.32N, G-6) compared to lower fusing temperatures. Frit at an end firing temperature of 1200 °C was significantly higher (214.52N, F-6) compared to lower fusing temperatures. Optical microscopy showed that Glass group G-6 (1200°C, EFT) had a thickness range from .09 to 0.03 mm while for Glass-A (1050°C, EFT) it was 0.5 mm.
CONCLUSIONS. Within the limitations of this study, we concluded that sandblasted bars didn’t significantly increase the means load to failure values compared to as-sintered groups. Coating the bars with Monobond-Plus had a significantly higher load to failure compared to as-sintered and sandblasted groups. VM9, Glass and Frit at an end firing temperature of 1200 °C showed significantly higher means load to failure compared to lower fusing temperature groups. / 2018-09-28T00:00:00Z
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Structural Modeling and Optimization of a Joined-Wing Configuration of a High-Altitude Long-Endurance (HALE) AircraftKaloyanova, Valentina B. January 2009 (has links)
No description available.
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An Experimental Investigation of a Joined Wing Aircraft Configuration Using Flexible, Reduced Scale Flight Test VehiclesRichards, Jenner 22 October 2014 (has links)
The United States Air Force has specified a need for the next generation, High Altitude, Long Endurance aircraft capable of carrying advanced sensor arrays over very large distances and at extreme altitudes. These extensive set of requirements has required a radical shift away from the conventional wing & tube configurations with a new focus placed on extremely light weight and unconventional structural and aerodynamic configurations. One such example is the Boeing Joined wing SensorCraft Concept.
The Joined wing concept has potential structural and sensor carrying benefits, but along with these potential benefits come several challenges. One of the primary concerns is the aeroelastic response of the aft wing, with potential adverse behaviours such as flutter and highly nonlinear structural behaviour of the aft wing under gust conditions. While nonlinear computation models have been developed to predict these responses, there exists a lack of experimental ground and flight test data for this unique joined wing configuration with which to benchmark the analytical predictions. The goal of this work is to develop a 5m, scaled version of the Boeing Joined Wing configuration and collect data, through a series of ground and flight based tests, which will allow designers to better understand the unique structural response of the configuration.
A computational framework was developed that is capable of linearly scaling the aeroelastic response of the full scale aircraft and optimize a reduced scale aircraft to exhibit equivalent scaled behaviour. A series of reduced complexity models was developed to further investigate the flying characteristics of the configuration, test avionics and instrumentation systems and the develop flight control laws to adequately control the marginally stable aircraft. Lessons learned were then applied the 5m flight test article that was designed and constructed by the author.
In the final stage of the project, the decision was made to relax the aeroelastically scaled constraint in order to allow additional softening of the structure to further investigate the nonlinear behaviour of the aircraft. Due to the added risk and complexity of flying this highly flexible aircraft the decision was made to produce the final aeroelastically scaled article at the 1.85m scale. This model was designed, developed and ground tested in the lead up to a follow on project which will see additional flight testing performed in conjunction with Boeing Inc. / Graduate
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Government department core business - managing the impact of potential conflicts on regional development projects and programsRodgers-Bell, Chloe Unknown Date (has links)
This research investigated core business conflict that occurs amongst government agencies when working together in regional development projects and initiatives. The intent is to develop methods to manage this conflict and so enhance the delivery of regional development outcomes. The research problem explored is: ‘Government Department core business – managing the impact of potential conflicts on regional development projects and programs’The research involves three discipline areas – Government and governance, public sector management practices, and regional development. Government agency (GA) core business is determined by Government and delivered using public sector management practices that have shaped individual agency’s strategic plans, processes and systems for core business delivery. Regional development involves multiple agencies delivering their core business outcomes that contribute to regional development. Due to the focus by each agency on their own core business, core business conflict can occur when agencies work together.A literature review did not uncover literature or research about GA core business conflict, therefore this is a new area of investigation. The literature studies and reports investigated and discussed a related area – issues and impediment to Whole-of- Government (WOG) and ‘joined-up’ government initiatives.A qualitative inquiry methodology is used to build knowledge about this new area. The sample of participants is drawn from GAs’ staff who are involved in regional development projects and programs, or projects and programs that contribute to regional development. Data collection is through interviews and surveys with GAs’ representatives from 18 agencies, across three levels of Government and from two distinctly different regions (coastal and inland).Two aspects of core business conflict are investigated – fundamental core business conflict that involves the underpinning philosophy and ideology of an agency, and functional/operational core business conflicts that include the strategic plans, policies, procedures and systems involved in delivery of core business, which also influence the design of program and project guidelines, and determine funding and staff resourcing.Research findings contribute new knowledge and expand current knowledge regarding challenges and barriers to agencies working together. Findings also enhance the application of approaches and tools to facilitate effective WOG and collaborative agency work.The research has resulted in a ‘process’ model to resolve the research problem that applies a holistic and comprehensive operational approach to addressing core business conflict. The ‘process’ model builds on the research findings and draws on information and tools from the literature.The research has implications for theory, policy and practice in the three discipline areas involved in the research problem and as a new area investigated, has generated further research opportunities.
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Government department core business - managing the impact of potential conflicts on regional development projects and programsRodgers-Bell, Chloe Unknown Date (has links)
This research investigated core business conflict that occurs amongst government agencies when working together in regional development projects and initiatives. The intent is to develop methods to manage this conflict and so enhance the delivery of regional development outcomes. The research problem explored is: ‘Government Department core business – managing the impact of potential conflicts on regional development projects and programs’The research involves three discipline areas – Government and governance, public sector management practices, and regional development. Government agency (GA) core business is determined by Government and delivered using public sector management practices that have shaped individual agency’s strategic plans, processes and systems for core business delivery. Regional development involves multiple agencies delivering their core business outcomes that contribute to regional development. Due to the focus by each agency on their own core business, core business conflict can occur when agencies work together.A literature review did not uncover literature or research about GA core business conflict, therefore this is a new area of investigation. The literature studies and reports investigated and discussed a related area – issues and impediment to Whole-of- Government (WOG) and ‘joined-up’ government initiatives.A qualitative inquiry methodology is used to build knowledge about this new area. The sample of participants is drawn from GAs’ staff who are involved in regional development projects and programs, or projects and programs that contribute to regional development. Data collection is through interviews and surveys with GAs’ representatives from 18 agencies, across three levels of Government and from two distinctly different regions (coastal and inland).Two aspects of core business conflict are investigated – fundamental core business conflict that involves the underpinning philosophy and ideology of an agency, and functional/operational core business conflicts that include the strategic plans, policies, procedures and systems involved in delivery of core business, which also influence the design of program and project guidelines, and determine funding and staff resourcing.Research findings contribute new knowledge and expand current knowledge regarding challenges and barriers to agencies working together. Findings also enhance the application of approaches and tools to facilitate effective WOG and collaborative agency work.The research has resulted in a ‘process’ model to resolve the research problem that applies a holistic and comprehensive operational approach to addressing core business conflict. The ‘process’ model builds on the research findings and draws on information and tools from the literature.The research has implications for theory, policy and practice in the three discipline areas involved in the research problem and as a new area investigated, has generated further research opportunities.
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Linear Finite Element Modeling of Joined Structures with Riveted ConnectionsKim, Jueseok 28 October 2019 (has links)
No description available.
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STRUCTURAL ANALYSIS OF REINFORCED SHELL WING MODEL FOR JOINED-WING CONFIGURATIONNARAYANAN, VIJAY 13 July 2005 (has links)
No description available.
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STRUCTURAL ANALYSIS OF AN EQUIVALENT BOX-WING REPRESENTATION OF SENSORCRAFT JOINED-WING CONFIGURATION FOR HIGH-ALTITUDE, LONG-ENDURANCE (HALE) AIRCRAFTMARISARLA, SOUJANYA 13 July 2005 (has links)
No description available.
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