Barrett, The Honors College Thesis/Creative Project Collection
Barrett, The Honors College at Arizona State University proudly showcases the work of undergraduate honors students by sharing this collection exclusively with the ASU community.
Barrett accepts high performing, academically engaged undergraduate students and works with them in collaboration with all of the other academic units at Arizona State University. All Barrett students complete a thesis or creative project which is an opportunity to explore an intellectual interest and produce an original piece of scholarly research. The thesis or creative project is supervised and defended in front of a faculty committee. Students are able to engage with professors who are nationally recognized in their fields and committed to working with honors students. Completing a Barrett thesis or creative project is an opportunity for undergraduate honors students to contribute to the ASU academic community in a meaningful way.
Displaying 1 - 4 of 4
Description
This experiment used hotwire anemometry to examine the von Kármán vortex street and how different surface conditions affect the wake profile of circular airfoils, or bluff bodies. Specifically, this experiment investigated how the various surface conditions affected the shedding frequency and Strouhal Number of the vortex street as Reynolds Number is increased. The cylinders tested varied diameter, surface finish, and wire wrapping. Larger diameters corresponded with lower shedding frequencies, rougher surfaces decreased Strouhal Number, and the addition of thick wires to the surface of the cylinder completely disrupted the vortex shedding to the point where there was almost no dominant shedding frequency. For the smallest diameter cylinder tested, secondary dominant frequencies were observed, suggesting harmonics.
ContributorsCoote, Peter John (Author) / Takahashi, Timothy (Thesis director) / White, Daniel (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The purpose of this paper is to discover what geometric characteristics of a wing and airfoil help to maximize leading edge suction through experimental testing. Three different stages of testing were conducted: a Proof of Concept, a Primary Experiment, and a Secondary Experiment. The Proof of Concept shows the effects of leading edge suction and the benefits it can posses. The Primary Experiment provided inconclusive data due to inaccuracies in the equipment. As a result, the Secondary Experiment was conducted in order to reduce the error effect as much as possible on the data. Unfortunately the Secondary Experiment provided inaccurate data as well. However, this paper does provide enough evidence to begin to question some of the long held beliefs regarding theoretical induced drag and whether it is true under all circumstances, or if it is only a good approximation for airfoils with full leading-edge suction effects.
ContributorsMorrow, Martin (Author) / Takahashi, Timothy (Thesis director) / Middleton, James (Committee member) / School for the Engineering of Matter, Transport, and Energy (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
It is a common assumption in the bicycle industry that stiffer frames generally perform better than flexible frames, because they transfer power more efficiently and absorb less energy from the rider's pedal stroke in the form of spring potential energy. However, in the last few years, Jan Heine of Bicycle Quarterly has developed an alternative theory, which he calls "planing", whereby a flexible frame can improve rider performance by not resisting the leg muscles as much, preventing premature muscle fatigue and allowing the rider to actually produce more consistent power, an effect which overwhelms any difference in power transfer between the different stiffness levels of frames. I performed several tests in which I measured the power input to the bicycle through the crankset and power output through a power-measuring trainer in the place of the rear hub. Heart rate data was collected along with most of these tests. Four bicycles were used with three distinct levels of stiffness. After performing several ANOVA tests to determine the effect of stiffness on the parameters of average power output during a sprint, maximum power output during a sprint, maximum heart rate during a sprint, difference between power-in and power-out during both sprints and longer efforts, and power quotient during a sprint, I found no effects of frame stiffness on any of these factors except power quotient. The finding for power quotient suggests a positive relationship between quotient and stiffness, which directly refutes the Planing Theory for the test riders and levels of stiffness represented in this test. Also, no statistically significant effect of stiffness on the difference between power-in and power-out was found, refuting the Power Transfer Theory for the riders and levels of stiffness represented in this test.
ContributorsSparks, Graham Philip (Author) / Takahashi, Timothy (Thesis director) / Middleton, James (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
This paper describes an aircraft design optimization tool for wave drag reduction. The tool synthesizes an aircraft wing and fuselage geometry using the Rhinoceros CAD program. It then implements an algorithm to perform area-ruling on the fuselage. The algorithm adjusts the cross-sectional area along the length of the fuselage, with the wing geometry fixed, to match a Sears-Haack distribution. Following the optimization of the area, the tool collects geometric data for analysis using legacy performance tools. This analysis revealed that performing the optimization yielded an average reduction in wave drag of 25% across a variety of Mach numbers on two different starting geometries. The goal of this project is to integrate this optimization tool into a larger trade study tool as it will allow for higher fidelity modeling as well as large improvements in transonic and supersonic drag performance.
ContributorsLeader, Robert William (Author) / Takahashi, Timothy (Thesis director) / Middleton, James (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12