Matching Items (479)
Description
With the growth of the additive manufacturing (AM) industry for metal components, there is an economic pressure for improved AM processes to overcome the shortcomings of current AM technologies (i.e., limited deposition rates, surface roughness, etc.). Unfortunately, the development of these processes can be time and capital-intensive due to the large

With the growth of the additive manufacturing (AM) industry for metal components, there is an economic pressure for improved AM processes to overcome the shortcomings of current AM technologies (i.e., limited deposition rates, surface roughness, etc.). Unfortunately, the development of these processes can be time and capital-intensive due to the large number of input parameters and the sensitivity of the process’s outputs to said inputs. There consequently has been a strong push to develop computational design tools (such as CFD models) which can decrease the time and cost of AM technology developments. However, many of the developments that have been made to simulate AM through CFD have done so on custom CFD packages (as opposed to commercially available packages), which increases the barrier to entry of employing computational design tools. For that reason, this paper has demonstrated a method for simulating fused deposition modeling using a commercially available CFD package (Fluent). The results from this implementation are qualitatively promising when compared to samples produced by existing metal AM processes, however additional work is needed to validate the model more rigorously and to reduce the computational cost. Finally, the developed model was used to perform a parameter sweep, thereby demonstrating a use case of the tool to help in parameter optimization.
Created2024-05
DescriptionAcademic interests combined into a speculative science fiction novel. Concepts from American Sign Language, mechanical engineering, and journalism studies were all utilized during development of the novel.
ContributorsGraziano, River (Author) / Irish, Jennifer (Thesis director) / Bell, Matt (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Department of English (Contributor)
Created2024-05
Description
The Tesla valve, originating from Nikola Tesla's "valvular conduit" patent in 1920, offers a unique solution to fluid control challenges by enabling unidirectional flow while impeding reverse flow. With applications ranging from fluid pumps to high-power engines, Tesla's design functions as a fluidic diode, inducing pressure drops across the valve

The Tesla valve, originating from Nikola Tesla's "valvular conduit" patent in 1920, offers a unique solution to fluid control challenges by enabling unidirectional flow while impeding reverse flow. With applications ranging from fluid pumps to high-power engines, Tesla's design functions as a fluidic diode, inducing pressure drops across the valve to define its efficiency through diodicity. Through computational fluid dynamics (CFD) simulations using ANSYS Fluent, the impact of removing the bifurcated section on Tesla valve efficiency is explored. The T45-R, D-Valve, and GMF Valve designs are analyzed across a range of Reynolds numbers (Re). Results show that while the absence of bifurcation can lead to higher diodicity values due to increased flow divergence and vortex formation, efficiency varies depending on flow conditions. The T45-R valve exhibits linear diodicity increase with Reynolds number, plateauing at higher values due to reduced fluid inertia influence. Conversely, the D-Valve with bifurcation excels at lower Re values, while the non-bifurcated version proves more efficient at higher Re values. The GMF Valve with bifurcation demonstrates efficiency at lower Re values but decreases in effectiveness as Re rises, with the non-bifurcated version showing lower efficiency overall. Overall, this research provides insights into the fundamental physics and design considerations of Tesla valves, offering guidance for optimizing fluid control applications across diverse industries. The study underscores the importance of considering geometric variations and flow conditions when designing Tesla valves for specific applications, highlighting the intricate relationship between valve geometry, flow dynamics, and efficiency.
ContributorsWiley, Sean (Author) / Huang, Huei-Ping (Thesis director) / Kim, Jeonglae (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2024-05
Description
This thesis examines how a recently proposed concept for a highly-truncated aerospike nozzle can be expected to perform at altitudes corresponding to ambient pressures from sea-level to full vacuum conditions, as would occur during second-stage ascent and during second-stage descent and return to Earth. Of particular importance is how the base pressure varies

This thesis examines how a recently proposed concept for a highly-truncated aerospike nozzle can be expected to perform at altitudes corresponding to ambient pressures from sea-level to full vacuum conditions, as would occur during second-stage ascent and during second-stage descent and return to Earth. Of particular importance is how the base pressure varies with ambient pressure, especially at low ambient pressures for which the resulting highly underexpanded flows exiting from discrete thrust chambers around the truncated aerospike merge to create a closed (unventilated) base flow. The objective was to develop an approximate but usefully accurate and technically rooted way of estimating conditions for which the jets issuing from adjacent thrust chambers will merge before the end of the truncated aerospike is reached. Three main factors that determine the merging distance are the chamber pressure, the altitude, and the spacing between adjacent thrust chambers. The Prandtl-Meyer expansion angle was used to approximate the initial expansion of the jet flow issuing from each thrust chamber. From this an approximate criterion was developed for the downstream distance at which the jet flows from adjacent thrust chambers merge. Variations in atmospheric gas composition, specific heat ratio, temperature, and pressure with altitude from sea-level to 600 km were accounted for. Results showed that with decreasing atmospheric pressure during vehicle ascent, the merging distance decreases as the jet flows become increasingly under-expanded. Increasing the number of thrust chambers decreases the merging distance exponentially, and increasing chamber pressure results in a decrease of the merging distance as well.
ContributorsHerrington, Katie (Author) / Dahm, Werner (Thesis director) / Takahashi, Timothy (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Department of Physics (Contributor)
Created2024-05
DescriptionThe Level Set Method was implemented via a coupled two-dimensional G-equation approach in successive axial segments.
ContributorsPodbielski, Adam (Author) / Dahm, Werner (Thesis director) / Waterhouse, Andrew (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2024-05
Description
This project involved testing and characterization on a shock loaded sample with a single engineered defect to study the effect of inclusions in engineering alloys. The sample was a single crystal copper with an embedded tungsten wire. Hardness testing and EBSD analysis were performed as independent methods of characterizing the

This project involved testing and characterization on a shock loaded sample with a single engineered defect to study the effect of inclusions in engineering alloys. The sample was a single crystal copper with an embedded tungsten wire. Hardness testing and EBSD analysis were performed as independent methods of characterizing the effect of a single defect on the adjacent material after a dynamic test. The objective was to define a region of the engineered defect's influence and quantify its effect for improved damage models and material design. EBSD images and hardness results complemented each other, showing evidence of plastic deformation and work hardening in the region around the tungsten wire that decreased moving radially further from it.
ContributorsPeterson, Camden (Author) / Peralta, Pedro (Thesis director) / Rajagopalan, Jagannathan (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2024-05
Description
In this thesis, we identify and analyze several chosen themes of Asian American identity that we feel are touched on in interesting ways within the body of films and media we’ve chosen to focus on. We do not argue that these themes are the most important for all Asian Americans,

In this thesis, we identify and analyze several chosen themes of Asian American identity that we feel are touched on in interesting ways within the body of films and media we’ve chosen to focus on. We do not argue that these themes are the most important for all Asian Americans, but we do believe that these themes reflect some of the commonly discussed questions of Asian American identity, particularly within the mainstream middle class. In one vein, these themes underline desires and longing present within Asian America and parallel competing notions of exclusion and integration: dreams of success, belonging, and connection.
ContributorsYao, Michelle (Author) / Wang, Sherry (Co-author) / Takada, Emy (Thesis director) / Kuo, Karen (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2024-05
Description

Phthalates are ubiquitous in the built environment and are used across various fields, despite known endocrine disruptive properties, and other associated health hazards, including abnormalities in reproductive health and development. I investigated the presence of phthalates in the built environment using the Health Product Declaration (HPD) repository to survey for

Phthalates are ubiquitous in the built environment and are used across various fields, despite known endocrine disruptive properties, and other associated health hazards, including abnormalities in reproductive health and development. I investigated the presence of phthalates in the built environment using the Health Product Declaration (HPD) repository to survey for products containing these chemicals, investigated the literature for possible health effects and alternatives to phthalates, and conducted a laboratoy-based feasibility study of urinary biomarkers associated with phthalates using wastewater-based epidemiology (WBE) on a US university campus at the building-scale. Of the 5,278 products in the HPD repository, 73 contained phthalates and were most commonly found in windows, doors, flooring, sealants, insulations, and furnishings. Alternative plasticizers (cardanol, epoxidized soybean oil, hydrogenated castor oil) usage were identified in 10 products from HPD repository. The two wastewater samples analyzed by liquid chromatography-tandem mass spectrometry (LC-MS-MS) showed that dimethyl phthalate (DMP) was detectable, as well as its human metabolite, monomethyl phthalate (MMP), observed at a concentration of 163-202 ng/L. These results indicate low human exposure from the building materials in the limited convenience sample investigated. Future studies of building scale wastewater-based epidemiology are recommended to investigate these and other phthalates commonly found in the built environment, including diisononyl phthalate (DINP) and diisononyl hexahydrophthalate (DINCH).

ContributorsGroves, Megan (Author) / Halden, Rolf (Thesis director) / Driver, Erin (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2023-05
Description

During the Dawn mission, bright spots were discovered on the surface of the dwarf planet Ceres, which were determined to be evaporite deposits of sodium carbonate, ammonium carbonate, and hydrohalite. These deposits are significant because they indicate the presence of subsurface water and potential geologic activity on Ceres. These evaporites

During the Dawn mission, bright spots were discovered on the surface of the dwarf planet Ceres, which were determined to be evaporite deposits of sodium carbonate, ammonium carbonate, and hydrohalite. These deposits are significant because they indicate the presence of subsurface water and potential geologic activity on Ceres. These evaporites form from the brine-water mixture in the deep Ceres reservoir, which likely possesses the conditions ideal for forming complex organics. Here, we report the results of a suite of laboratory techniques (CHN Elemental Analyzer, Secondary Ion Mass Spectrometry, Fourier-Transform Infrared Spectroscopy, Gas Chromatography, and Brunauer-Emmett-Teller Analysis) for quantifying the likelihood of primordial carbon survival and distribution in analog materials found on Ceres, particularly in salt evaporates. We are specifically looking at if the amino acid glycine can be preserved in sodium chloride crystals. Our results conclude that if the Ceres brine reservoir is saturated with organics, and with the lower limits that we have for our instrumentation thus far, these techniques should be more than sufficient to measure glycine content should we ever receive samples from Ceres.

ContributorsReynoso, Lucas (Author) / Bose, Maitrayee (Thesis director) / Castillo-Rogez, Julie (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / School of Earth and Space Exploration (Contributor)
Created2023-05
Description

This creative project is centered around the development and pitch of a 10-hour TV series consisting of story and character documents, pitch deck and pitch script; a full length draft of the series pilot is included. Development of the series' story and characters were done alongside Thesis Director Peter Murrieta.

ContributorsLe, Brian (Author) / Murrieta, Peter (Thesis director) / Bernstein, Gregory (Committee member) / Barrett, The Honors College (Contributor) / The Sidney Poitier New American Film School (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2023-05