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The purpose of my Honors Thesis was to generate a tool that could be implemented by Aerospace students at Arizona State University. This tool was created using MatLab which is the current program students are using. The modeling system that was generated goes step-by-step through the flow of a two spool gas turbine engine. The code was then compared to an ideal case engine with predictable values. It was found to have less than a 3 percent error for these parameters, which included optimal net work produced, optimal overall pressure ratio, and maximum pressure ratio. The modeling system was then run through a parametric analysis. In the first case, the bypass ratio was set to 0 and the freestream Mach number was set to 0. The second case was with a bypass ratio of 0 and fresstream Mach number of 0.85. The third case was with a bypass ratio of 5 and freestream Mach number of 0. The fourth case was with a bypass ratio of 5 and fresstream Mach number of 0.85. Each of these cases was run at various overall pressure ratios and maximum Temperatures of 1500 K, 1600 K and 1700 K. The results modeled the behavior that was expected. As the freestream Mach number was increased, the thrust decreased and the thrust specific fuel consumption increased, corresponding to an increase in total pressure at the combustor inlet. It was also found that the thrust was increased and the thrust specific fuel consumption decreased as the bypass ratio was increased. These results also make sense as there is less airflow passing through the engine core. Finally the engine was compared to two real engines. Both of which are General Electric G6 series engines. For the 80C2A3 engine, the percent difference between thrust and thrust specific fuel consumption was less than five percent. For the 50B, the thrust was below a two percent difference, but the thrust specific fuel consumption clearly provided inaccurate results. This could be caused by the lack of inputs provided by General Electric. The amount of fuel injected is largely dependent on the maximum temperature which is not available to the public. Overall, the code produces comparable results to real engines and can display how isolating and modifying a certain parameter effects engine performance.
ContributorsCook, Rachel Nicole (Author) / Dahm, Werner (Thesis director) / Lee, Taewoo (Committee member) / Wells, Valana (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2015-05
Description
The thesis is an investigation on current regulations of commercial aircraft landing and take-off procedures and an analysis of potential weaknesses within the regulatory system for commercial aerospace. To determine such flaws, an area of worse-case scenarios with regard to the aforementioned flight operations was researched. The events selected to best-depict these scenarios where incidents of aircraft overrunning the runway, referred to as runway excursions. A case-study conducted of 44 federal investigations of runway excursions produced data indicating four influential factors within these incidents: weather, pilot error, instrument malfunction, and runway condition. Upon examination, all but pilot error appeared to have federal enforcement to diminish the occurrence of future incidents. This is a direct result of the broad possibilities that make up this factor. The study then searched for a consistent fault within the incidents with the results indicating an indirect relationship of thrust reversers, a technique utilized by pilots to provide additional braking, to these excursions. In cases of thrust reverser failure, pilots' over-reliance on the system lead to time being lost from the confusion produced by the malfunction, ultimately resulting in several different runway excursions. The legal implication with the situation is that current regulations are ambiguous on the subject of thrust reversers and thus do not properly model the usage of the technique. Thus, to observe the scope of danger this ambiguity presents to the industry, the relationship of the technique to commercial aerospace needed to be determined. Interviews were set-up with former commercial pilots to gather data related to the flight crew perspective. This data indicated that thrust reversers were actively utilized by pilots within the industry for landing operations. The problem with the current regulations was revealed that the lack of details on thrust reverser reflected a failure of regulations to model current industry flight operations. To improve safety within the industry, new data related to thrust reverser deployment must be developed and enforced to determine appropriate windows to utilize the technique, thus decreasing time lost in confusion that results from thrust reversers malfunction. Future work would be based on producing simulations to determine said data as well as proposing the policy suggestions produced by this thesis.
ContributorsCreighton, Andrew John (Author) / Takahashi, Timothy (Thesis director) / Marchant, Gary (Committee member) / Kimberly, Jimmy (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Politics and Global Studies (Contributor)
Created2014-05
Description
In this paper, the effectiveness and practical applications of cooling a computer's CPU using mineral oil is investigated. A computer processor or CPU may be immersed along with other electronics in mineral oil and still be operational. The mineral oil acts as a dielectric and prevents shorts in the electronics while also being thermally conductive and cooling the CPU. A simple comparison of a flat plate immersed in air versus mineral oil is considered using analytical natural convection correlations. The result of this comparison indicates that the plate cooled by natural convection in air would operate at 98.41[°C] while the plate cooled by mineral oil would operate at 32.20 [°C]. Next, CFD in ANSYS Fluent was used to conduct simulation with forced convection representing a CPU fan driving fluid flow to cool the CPU. A comparison is made between cooling done with air and mineral oil. The results of the CFD simulation results indicate that using mineral oil as a substitute to air as the cooling fluid reduced the CPU operating temperature by sixty degrees Celsius. The use of mineral oil as a cooling fluid for a consumer computer has valid thermal benefits, but the practical challenges of the method will likely prevent widespread adoption.
ContributorsTichacek, Louis Joseph (Author) / Huang, Huei-Ping (Thesis director) / Herrmann, Marcus (Committee member) / Middleton, James (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Winglets and wingtip structures have been prominent in commercial aircraft design in the past few decades. These designs are known to reduce the induced drag on an aircraft wing, thus increasing its overall fuel efficiency. Several different winglet designs exist, and little reason is offered as to why different winglet designs are used in practice on different aircraft, especially those of variable range. This research tests existing winglets (no winglet, raked winglet, flat plate winglet, blended winglet, and wingtip fence) on a span-constrained wing planform design both computationally and in the wind tunnel. While computational tests using a vortex lattice code indicate that the wingtip fence minimizes induced drag and maximizes lift to drag ratio in most cases, wind tunnel tests show that at different lift coefficients and angles of attack, the raked winglet and blended winglet optimize the aerodynamic efficiency at incompressible flow velocities. Applying the wing aerodynamic data to existing variable range commercial aircraft, mission performance analysis is run on a Bombardier CRJ200, Airbus A320, and Airbus A340-300. By comparing flight lift coefficients in cruise for these aircraft to the lift coefficients at which winglets minimize drag in compressible flows, optimal winglet designs are chosen. It is found that the short range CRJ200 is best equipped with a flat plate or blended winglet, the medium range A320 can reduce drag with either a wingtip fence, raked winglet, or blended winglet, and the long range A340 performs best with a flat plate, blended, or raked winglet. Overall, despite the discrepancy in winglet selection depending on which experimental results are used, it is clear that addition of a winglet to a span-constrained wing is beneficial in that it reduces induced drag and therefore increases overall fuel efficiency.
ContributorsOremland, Joshua Elan (Author) / Wells, Valana (Thesis director) / Mertz, Benjamin (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Materials Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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
Description
This paper outlines the development of a script which utilizes a series of user-defined input parameters to construct base-level CAD models of aircraft landing gear. With an increased focus on computation development of aircraft models to allow for a rapidprototyping design process, this program seeks to allow designers to check for the validity of design integration before moving forward on systems testing. With this script, users are able to visually analyze the landing gear configurations on an aircraft in both the gear up and gear down configuration. The primary purpose this serves is to determine the validity of the gear's potential to fit within the limited real estate on an aircraft body. This, theoretically, can save time by weeding out infeasible designs before moving forward with subsystem performance testing. The script, developed in Python, constructs CAD models of dual and dual-tandem main landing gear configurations in the CAD program Rhino5. With an included design template consisting of 33 parameters, the script allows for a reasonable trade off between conciseness and flexibility of design.
ContributorsPatrick, Noah Edward (Author) / Takahashi, Timothy (Thesis director) / Middleton, James (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This paper presents an experimental investigation into the effects of altering electrode surface area roughness on thermogalvanic cell performance. A temperature difference between two electrodes was induced and brought to steady state to achieve a difference of around 50 °C, which was maintained with a DC power generated hot wire and a pumped ice bath. The open-circuit voltage values at steady-state were measured by a programed multimeter and the temperatures were measured by a series of type K thermocouples. Electrode surface area roughness was altered using different grit values of sandpaper and measuring the values using a Zescope Optical Profilometer. Once three different surface area average values were achieved, 6 trials were performed with 2 trials per roughness value. The results were tabulated in Section 4 of this report.
It was predicted that increasing the surface area roughness would increase the number of electrons present in the reduction oxidation reaction and decrease the activation resistance of the thermogalvanic system. Decreasing the activation resistance, a component of total internal resistance, would therefore increase the power output of the cell by a small magnitude. The results showed that changing the surface area roughness of the Copper electrodes evidently had no effect on the outputs of the cell system. Additionally, the Seebeck coefficient was also unaffected by the presence of increased surface area roughness.
The work presented in the following paper is part of a continuing effort to better understand the performance of thermogalvanic cells and their heat to electrical energy transfer properties.
It was predicted that increasing the surface area roughness would increase the number of electrons present in the reduction oxidation reaction and decrease the activation resistance of the thermogalvanic system. Decreasing the activation resistance, a component of total internal resistance, would therefore increase the power output of the cell by a small magnitude. The results showed that changing the surface area roughness of the Copper electrodes evidently had no effect on the outputs of the cell system. Additionally, the Seebeck coefficient was also unaffected by the presence of increased surface area roughness.
The work presented in the following paper is part of a continuing effort to better understand the performance of thermogalvanic cells and their heat to electrical energy transfer properties.
ContributorsLopez, Maggie Marie (Author) / Phelan, Patrick (Thesis director) / Miner, Mark (Committee member) / School of Sustainability (Contributor) / School of Music (Contributor) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The traditional early design phase of an aircraft involves a design approach in which the model's characteristics are defined before the CAD model is built. This thesis discusses an alternative to the early design process employing the use of a parametric model. A parametric model is one in which its characteristics are defined as functions of input parameters that a user will choose, as opposed to being pre-defined. This allows for faster iterations of the CAD design of an aircraft going through its first design phases. In order to demonstrate the feasibility and efficiency, a tool was developed in the form of a script written in Python that compiles into a plugin that a user can install into Rhino. With a full template of about 70 parameters that have significant effects on the performance characteristics of an aircraft, a user with the plugin can generate a full model. The overall design phase and development of the script into a publicly available installation file is discussed below. Results for the thesis took the form of insight gained into the field of parametric modeling. After development and implementation, emphasis points such as generation time, focus on parameters with large effect on aircraft performance, and interpolation of parameters dependent upon others were concluded.
ContributorsElliott, Steven Joseph (Author) / Takahashi, Tim (Thesis director) / Middleton, James (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
This work summarizes the development of a dynamic measurement platform in a cryostat to measure sample temperature response to space-like conditions and the creation a MATLAB theoretical model to predict sample temperature responses in the platform itself. An interesting variable-emittance sample called a Fabry-Perot emitter was studied for its thermal homeostasis behavior using the two developments. Using the measurement platform, it was shown that there was no thermal homeostatic behavior demonstrated by the sample at steady state temperatures. Theoretical calculations show other ways to demonstrate the cooling homeostasis behavior through time-varying heat inputs. Factors within the system such as heat loss and thermal mass contributed to an inhibited sample performance in the platform. Future work will have to be conducted, not only to verify the findings of the initial experiments but also to improve the measurement platform and the theoretical model.
ContributorsBoman, Neal D (Author) / Wang, Liping (Thesis director) / Taylor, Syndey (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The purpose of this project is to assess how well today’s youth is able to learn new skills<br/>in the realm of engineering through online video-conferencing resources. Each semester of this<br/>last year, a class of students in both 3rd and 6th grade learned about computer-aided design (CAD)<br/>and 3D printing through their laptops at school. This was done by conducting online lessons of<br/>TinkerCAD via Zoom and Google Meet. TinkerCAD is a simple website that incorporates easy-to-learn skills and gives students an introduction to some of the basic operations that are used in<br/>everyday CAD endeavors. In each lesson, the students would learn new skills by creating<br/>increasingly difficult objects that would test both their ability to learn new skills and their overall<br/>enjoyment with the subject matter. The findings of this project reflect that students are able to<br/>quickly learn and retain new information relating to CAD. The group of 6th graders was able to<br/>learn much faster, which was expected, but the class of 3rd graders still maintained the<br/>knowledge gained from previous lessons and were able to construct increasingly complicated<br/>objects without much struggle. Overall, the students in both classes enjoyed the lessons and did<br/>not find them too difficult, despite the online environment that we were required to use. Some<br/>students found the material more interesting than others, but in general, the students found it<br/>enjoyable to learn about a new skill that has significant real-world applications
ContributorsWerner, Matthew (Author) / Song, Kenan (Thesis director) / Lin, Elva (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05