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Full-Text Articles in Engineering
Analysis Of Turbulent Flow Behavior In Helicopter Rotor Hub Wakes, Forrest Mobley
Analysis Of Turbulent Flow Behavior In Helicopter Rotor Hub Wakes, Forrest Mobley
Masters Theses
The rotor hub is one of the most important features of all helicopters, as it provides the pilot a means for controlling the vehicle by changing the characteristics of the main and tail rotors. The hub also provides a structural foundation for the rotors and allows for the rotor blades to respond to aerodynamic forces while maintaining controllability and stability. Due to the inherent geometry and high rate of rotation, the rotor hub in its current form acts a large bluff body and is the primary source of parasite drag on the helicopter, despite its relatively small size. The rotor …
Modeling Dynamic Stall For A Free Vortex Wake Model Of A Floating Offshore Wind Turbine, Evan M. Gaertner
Modeling Dynamic Stall For A Free Vortex Wake Model Of A Floating Offshore Wind Turbine, Evan M. Gaertner
Masters Theses
Floating offshore wind turbines in deep waters offer significant advantages to onshore and near-shore wind turbines. However, due to the motion of floating platforms in response to wind and wave loading, the aerodynamics are substantially more complex. Traditional aerodynamic models and design codes do not adequately account for the floating platform dynamics to assess its effect on turbine loads and performance. Turbines must therefore be over designed due to loading uncertainty and are not fully optimized for their operating conditions. Previous research at the University of Massachusetts, Amherst developed the Wake Induced Dynamics Simulator, or WInDS, a free vortex wake …
Computational Analysis Of A Wing Oscillator, Ryne Derrick Radermacher
Computational Analysis Of A Wing Oscillator, Ryne Derrick Radermacher
Masters Theses
An analysis of a newly proposed wind power extraction device called a wing oscillator was performed using computational fluid dynamics (CFD). A wing oscillator is a device that consists of two airfoils attached to a central pivot by means of a frame or shaft. Oscillatory motion is produced by controlling the angle of attack of the airfoils as a fluid flow is passed over the device. A robust mathematical scheme was developed to investigate the performance of the wing oscillator and was hooked to the CFD software package FLUENT through User Defined Functions (UDFs). Using the dynamic meshing analysis methods …
A Survey Of Gaps, Obstacles, And Technical Challenges For Hypersonic Applications, Timothy Andrew Barber
A Survey Of Gaps, Obstacles, And Technical Challenges For Hypersonic Applications, Timothy Andrew Barber
Masters Theses
The object of this study is to canvas the literature for the purpose of identifying and compiling a list of Gaps, Obstacles, and Technological Challenges in Hypersonic Applications (GOTCHA). The significance of GOTCHA related deficiencies is discussed along with potential solutions, promising approaches, and feasible remedies that may be considered by engineers in pursuit of next generation hypersonic vehicle designs and optimizations. Based on the synthesis of several modern surveys and public reports, a cohesive list is formed, consisting of widely accepted areas needing improvement and falling under several general categories. These include: aerodynamics, propulsion, materials, analytical modeling, CFD modeling, …