A wind tunnel test of a very flexible wing model has been conducted to collect data suitable for correlating with and validating nonlinear aeroelastic analysis methods. Nonlinear methods are necessary to accurately predict the response of high altitude long endurance vehicles such as the NASA Helios or the DARPA Vulture class of vehicles and very little test data is available for validating such methods. A 9 foot semi-span cantilever mounted flexible model was designed and built to withstand a wing tip deflection of 5 feet. The model included actuated control surfaces and a side wall turntable mount for adjusting angle of attack. The model was fully instrumented to collect structural response data and an optical deflection measurement system was utilized to collect deflection data. During seven days of testing and 132 runs, data was collected from over 700 hundred static test conditions and 200 dynamic conditions. During the testing, a low speed instability region was discovered and limit cycle oscillation behavior observed. A maximum wing tip deflection of 45 inches was achieved during the higher speed test conditions. NomenclatureAOA = Angle of Attack CMT = Cantilever Model Test HT = Horizontal Tail (positive (+) trailing edge down) MEMS = Micro Electro Mechanical Systems COTS = Commercial Off The Shelf UWAL = University of Washington Aeronautical Laboratory OML = Outer Mold Line DAQ = Data Acquisition System WT = Wing Tip Surface (positive (+) trailing edge down) I. Backgrounduture high altitude and extremely long endurance aircraft have mission requirements that challenge aircraft design. The very light weight structure and high aspect ratio wing designs required to meet performance requirements creates unique problems related to understanding and predicting the aeroelastic response of the vehicle. This class of vehicle can undergo large structural deflections in turbulence and operates very closely to aerodynamic stall limits. The investigation of the NASA Helios vehicle accident 1 emphasized the necessity to include these nonlinear effects in the aeroelastic models used for flight loads development, flight dynamics simulation and control design. The DARPA Vulture II program 2 is a recent entry into this class of vehicles with a 5 year uninterrupted
This study explores the individual and institutional factors that affect the scientific production of Ecuadorian universities. Through the design and application of a linear regression model, the affectation of each variable to the production as a whole is exposed. The results show that the institutional factors, projects and laboratories are significant and that they positively influence the final product of the scientific research process. Researchers and the number of PhDs that universities have are still of little significance despite their impact. The result says that women are less productive than men and that researchers produce more between the ages of 30 and 39. It is also established that the number of collaborators can have a negative effect. This information may allow decision-makers to consider incentives within the public policy framework of the National Higher Education System to promote higher levels of scientific production.
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