Aerospace Engineering Commons^™

Aerodynamics And Turbulent Wake-Flow Characteristics Of Owls During Flapping Flight, Krishnamoorthy Krishnan

Electronic Theses and Dissertations

Owls exhibit unique flight capabilities in the low Reynolds number flow regime which is prone to complex viscous flow phenomena. They possess unique feather features and flexible wing structures which are postulated to help them fly nearly silently and stably at low speeds in a complex flow setting. Understanding the aerodynamics of owls could pave the way to enhance the future designs of small flying vehicles. Though it has been a focus of research over multiple decades, no conclusive agreement has been attained on the aerodynamic mechanisms associated with owl flight. Particularly, the aerodynamics of flapping owl flight is severely …

Development And Testing Of A 1:70 Scale Model Wind Turbine Of The Iea Reference 15 Mw Floating Offshore System, Amber Parker

Electronic Theses and Dissertations

This thesis presents the development of a 1/70th scale performance-matched wind turbine intended for wind and wave basin model testing of commercially viable floating wind turbine structures based off of the International Energy Agency (IEA) Wind 15 MW design. The focus of this demonstration is to test active blade pitch response controls and to provide an experimental dataset for use by modelers and industry for future turbine improvements. Future research is planned to test the turbine in conjunction with an actively damping hull to test the interactions between the two control systems.

Outlined in this thesis are the methods of …

Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan

Electronic Theses and Dissertations

In recent years the development of rocket engines has been mainly focused on improving the engine cycle and creating new fuels. Rocket nozzle design has not been changed since the late 1960s. Recent needs for reliable and reusable rockets, as well as advancements in additive manufacturing, have brought new interest into the aerospike nozzle concept. This nozzle is a type of altitude adjusting nozzle that is up to 90% more efficient than bell nozzles at low altitudes and spends up to 30% less fuel. Since the nozzle body is submerged in the hot exhaust gasses it is difficult to keep …

A Non-Reacting Passive Scalar Comparison Of Starccm And Openfoam In A Supersonic Cavity Flame Holder, Thomas Nuese

Electronic Theses and Dissertations

The scramjet engine equipped with a modern-day airliner would allow for very quick travel across the United States. The major problem is that designing such an engine and testing it to make sure it is safe would cost millions if not billions of dollars. Computational fluid dynamics allows for complex designs to be tested but can still take many days, weeks, or even months to complete. With the use of computational fluid dynamics (CFD), the scramjet engine can be analyzed to determine a quicker way to test and develop a reliable configuration in addition to analyzing the effects of different …

Comparative Analysis Of Winglet Efficiency On Supercritical Versus Traditionally Cambered Airfoils, Evan Cathers

Electronic Theses and Dissertations

This study serves to define the performance of several industry-recognized and exploratory wing tip devices on aircraft wings utilizing contemporary supercritical airfoil geometry. For comparison, the same examination is performed on a wing comprised of traditionally cambered airfoils, the platform upon which winglets were initially developed. The supercritical wing design is based on that of the Airbus A320, while the conventional airfoil is based upon the Boeing 737-800 platform. Tip devices selected for analysis include blended, raked, split scimitar, fence, and spiroid winglets, as well as tip sails, characterized by the spreading of a bird’s primary flight feathers. Methodology for …