Matching Items (19)
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- All Subjects: Heat Transfer
- Creators: Mechanical and Aerospace Engineering Program
- Creators: El Asmar, Mounir
- Status: Published
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 creative thesis project is to create the framework of an educational class package based off of a course offered at Arizona State University. The course chosen for this project is an honors course titled Deductive Logic: Leadership and Management Techniques and is taught by Dean Kashiwagi, PhD. The class package is designed to be published over an online platform so students and professors from various institutions can access the material. Currently the platform is in its final stages of development and is slated to go live on July of 2014. The future development of the package will be geared towards facilitating interdisciplinary collaboration between institutions based off of course concepts.
ContributorsGunnoe, Jake Alan (Author) / Kashiwagi, Dean (Thesis director) / Kashiwagi, Jacob (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Del E. Webb Construction (Contributor)
Created2014-05
Description
The ASU Compact X-ray Free Electron Laser (CXFEL) is a first of its kind instrument that will illuminate the processes of life and allow scientists to create more effective treatments for disease. The dimensions of the linear accelerator (LINAC) cavities must remain stable during operation, for a change in the geometry alters the standing wave microwave energy resonance within the cavities and leads to reflected rather than coupled and useful microwave energy to electric field coupling. This disturbs the electron bunch acceleration dynamics critical to the ultimate generation of x-ray pulses. Cooling water must be supplied to the electron generating RF-GUN, and linear accelerator (LINAC) structures at unique flowrate and temperature setpoints that are specific to the operating mode of the CXFEL. Design specifications for the water supply to the RF-GUN and three LINACs and were made for the nominal operating mode, which adds a 3 kW heat load to the water. To maintain steady cavity dimensions, water must be supplied to each device under test at 30.0 ºC ± 0.06 ºC. The flowrate of water must be 3.5 GPM to the RF-GUN and 2.5 GPM to each of the three LINACs with ± 0.01 GPM flowrate resolution. The primary function of the Dedicated-Precision Thermal Trim Unit (D-PTTU) is to control the flowrate and temperature of water supply to each device under test. A simplified model of the system was developed to select valves that would meet our design specifications for flowrate and temperature control. After using this model for valve selection, a detailed system model was created to simulate relevant coupled-domain physics of the integrated system. The detailed system model was used to determine the critical sensitivities of the system and will be used to optimize the performance of the system in the future. Before the detailed system model can be verified and tuned with experiments, the sensors were calibrated in an ice-bath to ensure the sensors measure accurate and precise values. During initial testing, the D-PTTU was able to achieve ± 0.02 ºC temperature resolution, which exceeds the design specification by a factor of three.
ContributorsGardeck, Alex John (Author) / Holl, Mark (Thesis director) / Smith, Dean (Committee member) / Department of Physics (Contributor) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The temperature of exhaust pipes can be dangerous in dry areas where there is a lot of brush. The temperatures of exhaust pipes can reach a high enough temperature to start a fire if touching the dry brush, which ignites around 300°C. The goal of this project was to explore different techniques to limit the possibility of these brush fires. Specifically, different methods were explored to reduce the temperature of the pipe that would be contacting the brush. Fires can begin within seconds of contacting the hot exhaust pipes [10]. This experiment found that of the three options tested: exhaust wrap, heat sink with thermoelectric devices, and high temperature paint, adding a heat shield/sink is the best way to limit the high temperatures from igniting the brush. There was a cooling difference of nearly 100°C when a heat shield/sink was added to the bare pipe. The additional thermal mass as well as the finned heat sinks attached to the heat sink helped dissipate the heat from the pipe and release the waste heat into the surroundings. The increase in surface area in correspondence with forced convection from the surrounding air lowered the temperature of the metal in contact with the dry brush.
ContributorsHodges, Andrew (Author) / Benson, David (Thesis director) / Bocanegra, Luis (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This thesis project explains what thermal interface materials (TIMs) are, what they are used for, and how to measure their properties. Thermal interface materials are typically either a grease like paste or a soft polymer pad that is placed between two solids to increase the heat transfer rate. Solids in contact with each other experience a very large thermal contact resistance, this creates a thermal bottleneck which severely decreases the heat transfer from one solid to another. To solve this, particles with a high thermal conductivity are used as filler material in either a grease or polymer. A common application for TIMs is in computer components, where a TIM is used to remove the heat generated from computer chips. These materials allow for computer chips to run faster without overheating or throttling performance. However, further improvements to TIMs are still desired, which are needed for more powerful computer chips. In this work, a Stepped Bar Apparatus (SBA) is used to evaluate the thermal properties of TIMs. The SBA is based on Fourier’s Law of one-dimensional heat transfer. This work explains the fundamentals of the SBA measurement, and develops a reliable way to confirm the SBA’s measurement consistency through the use of reference samples. Furthermore, this work evaluates the effects of volume fraction and magnetic alignment on the performance of nickel flakes mixed into a polymer to create a soft TIM composite pad. Magnets are used to align the nickel flakes into a column like arrangement in the direction that heat will travel. Magnetic alignment increases the thermal conductivity of the composite pads, and has peak performance at low compression.
ContributorsHart, Matthew (Author) / Rykaczewski, Konrad (Thesis director) / Wang, Robert (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-12
Description
Nuclear power has recently experienced a resurgence in interest due to its ability to generate significant amounts of relatively clean energy. However, the overall size of nuclear power plants still poses a problem to future advancements. The bulkiness of components in the plant contribute to longer construction times, higher building and maintenance costs, and the isolation of nuclear plants from populated areas. The goal of this project was to analyze the thermal performance of nanocrystalline copper tantalum (NC Cu-Ta) inside the steam generator of a pressurized water reactor to see how much the size of these units could be reduced without affecting the amount of heat transferred through it. The analysis revealed that using this material, with its higher thermal conductivity than the traditional Inconel Alloy 600 that is typically used in steam generators, it is possible to reduce the height of a steam generator from 21 meters to about 18.6 meters, signifying a 11.6% reduction in height. This analysis also revealed a diminishing return that occurs with increasing the thermal conductivity on both reducing the required heat transfer area and increasing the overall heat transfer coefficient.
ContributorsRiese, Alexander (Author) / Phelan, Patrick (Thesis director) / Bocanegra, Luis (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The following report followed three separate construction crews at a construction site at ASU and performed labor productivity analysis to quantitatively measure the efficiency of the workers performing specific tasks. These crews were tasked with electrical wiring, concrete pouring, and drywall sanding. Crew balance measured the down time of individual crew members compared to the overall time spent on a task, and the results of these observations were calculated, and suggested improvements given.
ContributorsScollick, Evelyn (Author) / Grau, David (Thesis director) / Lamanna, Anthony (Committee member) / School of Film, Dance and Theatre (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This thesis examines the mechanical properties of an origami inspired structure and its equivalent cube counterpart to determine if this origami configuration is an effective load bearing and energy absorption structure. To test this, a folded paper model was created for visual realization and then 3D printed models were created to undergo compression testing using the Instron 4411. The data from testing was used to create stress-strain curves for each sample, which were then used to determine the maximum stress and toughness of each structure. The performance of these structures was also compared to other known material performance. The origami structure was found to outperform the equivalent cube in both maximum stress it could withstand before failure and toughness. These results are grounds for further research to be done to determine the validity of origami structures as viable alternatives to current material configurations.
ContributorsFong, Jessica (Author) / Jiang, Hanqing (Thesis director) / Kingsbury, Dallas (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Sustainable Materials Management and Circular Economy are both frameworks for considering the way we interact with the world's resources. Different organizations and institutions across the world have adopted one philosophy or the other. To some, there seems to be little overlap of the two, and to others, they are perceived as being interchangeable. This paper evaluates Sustainable Materials Management (SMM) and Circular Economy (CE) individually and in comparison to see how truly different these frameworks are from one another. This comparison is then extended into a theoretical walk-through of an SMM treatment of concrete pavement in contrast with a CE treatment. With concrete being a ubiquitous in the world's buildings and roads, as well as being a major constituent of Construction & Demolition waste generated, its analysis is applicable to a significant portion of the world's material flow. The ultimate test of differentiation between SMM and CE would ask: 1) If SMM principles guided action, would the outcomes be aligned with or at odds with CE principles? and conversely 2) If CE principles guided action, would the outcomes be aligned with or at odds with SMM principles? Using concrete pavement as an example, this paper seeks to determine whether or not Sustainable Materials Management and Circular Economy are simply different roads leading to the same destination.
ContributorsAbdul-Quadir, Anisa (Author) / Kelman, Candice (Thesis director) / Buch, Rajesh (Committee member) / Barrett, The Honors College (Contributor)
Created2017-05
Description
A public North American university needed a tool to automate their Vendor of Record rotation program. The goal was to give each vendor in the program fair opportunities and to be open and honest with how vendors were selected. This tool was created in Microsoft Excel with VBA to code macros. The three major Excel sheets are the Masters, the FM Interface, and the Executive Interface. The Masters act as a database and house data for each project. It is a plain Excel worksheet populated with tables. The FM Interface is a macro-enabled Excel workbook. It is distributed to every Facilities Manager in the program. The FM Interface communicates with the Masters in the background. The FMs use the various inputs and buttons to go through every step of procuring a project. They start by initializing a project, and are given a generated list of vendors who are qualified. This list is automatically rotated for every project. Then they fill in an RFQ and it is automatically emailed to the required vendors. When the Facilities Manager receives every quote, they input them into the program and they are saved to the database. When the project is complete, the manager must fill out a satisfaction survey to measure safety, cost, schedule, and quality of work. This is the main method of tracking vendor performance. The last sheet, the Executive Interface, is given only to the administrator of the program. It generates various reports, such as vendor performance, FM performance, and insurance status. It also has many administrative functions including insurance updating, vendor input, and delete project/vendor. The automated tool has been used without error on over 50 projects by 11 different Facilities Managers. The university's Facilities Management team is pleased with the automated process.
ContributorsSchneider, Steven Andrew (Author) / Sullivan, Kenneth (Thesis director) / Savicky, John (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12