Matching Items (189)
Description
Desorption processes are an important part of all processes which involve utilization of solid adsorbents such as adsorption cooling, sorption thermal energy storage, and drying and dehumidification processes and are inherently energy-intensive. Here, how those energy requirements can be reduced through the application of ultrasound for three widely used adsorbents namely zeolite 13X, activated alumina and silica gel is investigated. To determine and justify the effectiveness of incorporating ultrasound from an energy-savings point of view, an approach of constant overall input power of 20 and 25 W was adopted. To measure the extent of the effectiveness of using ultrasound, the ultrasonic-power-to-total power ratios of 0.2, 0.25, 0.4 and 0.5 were investigated and the results compared with those of no-ultrasound (heat only) at the same total power. Duplicate experiments were performed at three nominal frequencies of 28, 40 and 80 kHz to observe the influence of frequency on regeneration dynamics. Regarding moisture removal, application of ultrasound results in higher desorption rate compared to a non-ultrasound process. A nonlinear inverse proportionality was observed between the effectiveness of ultrasound and the frequency at which it is applied. Based on the variation of desorption dynamics with ultrasonic power and frequency, three mechanisms of reduced adsorbate adsorption potential, increased adsorbate surface energy and enhanced mass diffusion are proposed. Two analytical models that describe the desorption process were developed based on the experimental data from which novel efficiency metrics were proposed, which can be employed to justify incorporating ultrasound in regeneration and drying processes.
ContributorsDaghooghi Mobarakeh, Hooman (Author) / Phelan, Patrick (Thesis advisor) / Wang, Liping (Committee member) / Wang, Robert (Committee member) / Calhoun, Ronald (Committee member) / Deng, Shuguang (Committee member) / Arizona State University (Publisher)
Created2021
Description
The phase change process of freezing water is an important application in several fields such as ice making, food freezing technologies, pharmaceuticals etc. Due to the widespread usage of ice-related products, process improvements in this technology can potentially lead to substantial energy savings. After studying the freezing process of water, the supercooling phenomenon was found to occur which showed a negative effect. Therefore, ultrasound was proposed as a technique to reduce the supercooling effect and improve the heat transfer rate. An experimental study was conducted to analyze the energy expenditures in the freezing process with and without the application of ultrasound. After a set of preliminary experiments, an intermittent application of ultrasound at 10W & 3.5W power levels were found to be more effective than constant-power application, and were explored in further detail. The supercooling phenomenon was thoroughly studied through iterative experiments. It was also found that the application of ultrasound during the freezing process led to the formation of shard-like ice crystals. From the intermittent ultrasound experiments performed at 10W and 3.5W power levels, percentage energy enhancements relative to no ultrasound of 8.9% ± 12.4% and 11.9% ± 24.6% were observed, respectively.
ContributorsSubramanian, Varun (Author) / Phelan, Patrick (Thesis advisor) / Calhoun, Ronald (Committee member) / Rykaczewski, Konrad (Committee member) / Arizona State University (Publisher)
Created2021
Description
Climatic variables such as temperature have been shown to correlate with demand for mental health services in other countries. An attempt by the present study to replicate this correlation using existing USA treatment data on mental health was not substantiated. Using annual state-level data from 2007 through 2015, the rate of mental health service utilization per 1000 population was correlated with average temperature and precipitation, while adjusting for Gross Domestic Product (GDP), unemployment, and urbanization. No statistically significant correlation was found.
ContributorsPhelan, Patrick (Author) / Phelan, Bernadette (Author) / Ira A. Fulton Schools of Engineering (Contributor)
Created2017-10-08
Description
In this work, a selective solar absorber made of nanostructured titanium gratings deposited on an ultrathin MgF2 spacer and a tungsten ground film is proposed and experimentally demonstrated. Normal absorptance of the fabricated solar absorber is characterized to be higher than 0.9 in the UV, visible and, near infrared (IR) regime, while the mid-IR emittance is around 0.2. The high broadband absorption in the solar spectrum is realized by the excitation of surface plasmon and magnetic polariton resonances, while the low mid-IR emittance is due to the highly reflective nature of the metallic components. Further directional and polarized reflectance measurements show wide-angle and polarization-insensitive high absorption within solar spectrum. Temperature-dependent spectroscopic characterization indicates that the optical properties barely change at elevated temperatures up to 350 °C. The solar-to-heat conversion efficiency with the fabricated metamaterial solar absorber is predicted to be 78% at 100 °C without optical concentration or 80% at 400 °C with 25 suns. The performance could be further improved with better fabrication processes and geometric optimization during metamaterial design. The strong spectral selectivity, favorable diffuse-like behavior, and good thermal stability make the metamaterial selective absorber promising for significantly enhancing solar thermal energy harvesting in various systems at mid to high temperatures.
ContributorsWang, Hao (Author) / Sivan, Vijay Prasad (Author) / Mitchell, Arnan (Author) / Rosengarten, Gary (Author) / Phelan, Patrick (Author) / Wang, Liping (Author) / Ira A. Fulton Schools of Engineering (Contributor)
Created2015-06-01
Description
ABSTRACT
This project features five new pieces for clarinet commissioned from three different composers including:
1. Rasa by Jeffrey Ouper
2. Faerie Tale Dances by Jeffrey Ouper
3. Amalgamated Widget by Tavia Sullens
4. Faerie Suite by Theresa Martin
5. Time Lapse by Theresa Martin
Faerie Suite and Amalgamated Widget are for unaccompanied clarinet; Time Lapse is a trio for clarinet, bass clarinet, and piano; Faerie Tale Dances is a trio for E-flat clarinet, sopranino recorder, and toy piano; and Rasa is a quartet for E-flat clarinet, two A clarinets, and bass clarinet. These pieces challenge the performer in various ways, including complex rhythm, use of extended techniques such as glissando, flutter tongue, and circular breathing, and synthetic and non-traditional scales. The composers were given guidelines prior to the compositional process to create works with a thematic connection to mythology, folklore, or fairy tales, and inspired by dance and non-western or traditional harmonies and idioms. This document offers background information about the composers and the works, and a performance guide is included for each. This guide provides recommendations and suggestions for each piece. Also included are interviews with each of the composers. Accompanying this document are recordings of each of the five pieces, performed by the author.
This project features five new pieces for clarinet commissioned from three different composers including:
1. Rasa by Jeffrey Ouper
2. Faerie Tale Dances by Jeffrey Ouper
3. Amalgamated Widget by Tavia Sullens
4. Faerie Suite by Theresa Martin
5. Time Lapse by Theresa Martin
Faerie Suite and Amalgamated Widget are for unaccompanied clarinet; Time Lapse is a trio for clarinet, bass clarinet, and piano; Faerie Tale Dances is a trio for E-flat clarinet, sopranino recorder, and toy piano; and Rasa is a quartet for E-flat clarinet, two A clarinets, and bass clarinet. These pieces challenge the performer in various ways, including complex rhythm, use of extended techniques such as glissando, flutter tongue, and circular breathing, and synthetic and non-traditional scales. The composers were given guidelines prior to the compositional process to create works with a thematic connection to mythology, folklore, or fairy tales, and inspired by dance and non-western or traditional harmonies and idioms. This document offers background information about the composers and the works, and a performance guide is included for each. This guide provides recommendations and suggestions for each piece. Also included are interviews with each of the composers. Accompanying this document are recordings of each of the five pieces, performed by the author.
ContributorsApplegate, James Patrick (Author) / Spring, Robert (Thesis advisor) / Gardner, Joshua (Thesis advisor) / Holbrook, Amy (Committee member) / Arizona State University (Publisher)
Created2018
Description
This study focuses on three songs from stage works of Kurt Weill (1900-1950): “September Song” from Knickerbocker Holiday (1938), “Speak Low” from One Touch of Venus (1943), and “Lost in the Stars” from Lost in the Stars (1949). All from Weill’s time in the United States, these songs are adaptable as solos and have become American standards performed in various arrangements and styles of popular music by many different artists.
The first part of this study is a biographical sketch of Weill’s life and music. It is intended to provide context for the three songs by tracing his beginnings as a German composer of stage works with volatile political messages, to his flight to the United States and his emergence as a composer of Broadway successes.
The second part is a commentary on the composition of the three selected songs. The lyrics and musical content are examined to show how Weill’s settings convey the dramatic mood and meaning as well as the specific nuances of the words. Description of the context of these songs explains how they were textually and musically intended to advance the plot and the emotional arc of the dramatic characters. The popularity of these songs endures beyond their original shows, and so there is discussion of how other artists have adapted and performed them, and available recordings are cited.
Weill’s songs, his little masterpieces, have proven to be truly evocative and so attractive to American audiences that they have undergone myriad adaptations. This study seeks to provide the personal and historical background of Kurt Weill’s music and to demonstrate why these three songs in particular have proven to have such lasting appeal.
The first part of this study is a biographical sketch of Weill’s life and music. It is intended to provide context for the three songs by tracing his beginnings as a German composer of stage works with volatile political messages, to his flight to the United States and his emergence as a composer of Broadway successes.
The second part is a commentary on the composition of the three selected songs. The lyrics and musical content are examined to show how Weill’s settings convey the dramatic mood and meaning as well as the specific nuances of the words. Description of the context of these songs explains how they were textually and musically intended to advance the plot and the emotional arc of the dramatic characters. The popularity of these songs endures beyond their original shows, and so there is discussion of how other artists have adapted and performed them, and available recordings are cited.
Weill’s songs, his little masterpieces, have proven to be truly evocative and so attractive to American audiences that they have undergone myriad adaptations. This study seeks to provide the personal and historical background of Kurt Weill’s music and to demonstrate why these three songs in particular have proven to have such lasting appeal.
ContributorsKimball, Abigail S (Author) / May, Judy (Thesis advisor) / Holbrook, Amy (Committee member) / Kopta, Anne (Committee member) / Arizona State University (Publisher)
Created2016
Description
As part of a United States-Australian Solar Energy Collaboration on a Micro Urban Solar Integrated Concentrator project, the purpose of the research was to design and build a bench-top apparatus of a solar power concentrator thermal storage unit. This prototype would serve to be a test apparatus for testing multiple thermal storage mediums and heat transfer fluids for verification and optimization of the larger system. The initial temperature range for the system to test a wide variety of thermal storage mediums was 100°C to 400°C. As for the thermal storage volume it was decided that the team would need to test volumes of about 100 mL. These design parameters later changed to a smaller range for the initial prototype apparatus. This temperature range was decided to be 210°C to 240°C using tin as a phase change material (PCM). It was also decided a low temperature (<100°C) test using paraffin as the PCM would be beneficial for troubleshooting purposes.
ContributorsLee, William John (Author) / Phelan, Patrick (Thesis director) / Wang, Robert (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / School of International Letters and Cultures (Contributor)
Created2015-05
Description
Solar panels need to be both cost effective and environmentally friendly to compete with traditional energy forms. Photovoltaic recycling has the potential to mitigate the harm of waste, which is often landfilled, while putting material back into the manufacturing process. Out of many, three methods show much promise: Full Recovery End-of-Life Photovoltaic (FRELP), mechanical, and sintering-based recycling. FRELP recycling has quickly gained prominence in Europe and promises to fully recover the components in a solar cell. The mechanical method has produced high yields of valuable materials using basic and inexpensive processes. The sintering method has the potential to tap into a large market for feldspar. Using a levelized cost of electricity (LCOE) analysis, the three methods could be compared on an economic basis. This showed that the mechanical method is least expensive, and the sintering method is the most expensive. Using this model, all recycling methods are less cost effective than the control analysis without recycling. Sensitivity analyses were then done on the effect of the discount rate, capacity factor, and lifespan on the LCOE. These results showed that the change in capacity factor had the most significant effect on the levelized cost of electricity. A final sensitivity analysis was done based on the decreased installation and balance of systems costs in 2025. With a 55% decrease in these costs, the LCOE decreased by close to $0.03/kWh for each method. Based on these results, the cost of each recycling method would be a more considerable proportion of the overall LCOE of the solar farm.
ContributorsMeister, William Frederick (Author) / Goodnick, Stephen (Thesis director) / Phelan, Patrick (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Failures in the cold chain, the system of refrigerated storage and transport that provides fresh produce or other essentials to be maintained at desired temperatures and environmental conditions, lead to food and energy waste. The mini container (MC) concept is introduced as an alternative to conventional refrigerated trucks (“reefers”), particularly for small growers. The energy consumption and corresponding GHG emissions for transporting tomatoes in two cities representing contrasting climates is analyzed for conventional reefers and the proposed mini containers. The results show that, for partial reefer loads, using the MCs reduces energy consumption and GHG emissions. The transient behavior of the vapor compression refrigeration cycle is analyzed by considering each component as a “lumped” system, and the resulting sub-models are solved using the Runge Kutta 4th-order method in a MATLAB code at hot and cold ambient temperatures. The time needed to reach steady state temperatures and the temperature values are determined. The maximum required compressor work in the transient phase and at steady state are computed, and as expected, as the ambient temperature increases, both values increase. Finally, the average coefficient of performance (COP) is determined for varying heat transfer coefficient values for the condenser and for the evaporator. The results show that the average COP increases as heat transfer coefficient values for the condenser and the evaporator increase. Starting the system from rest has an adverse effect on the COP due to the higher compressor load needed to change the temperature of the condenser and the evaporator. Finally, the impact on COP is analyzed by redirecting a fraction of the cold exhaust air to provide supplemental cooling of the condenser. It is noted that cooling the condenser improves the system's performance better than cooling the fresh air at 0% of returned air to the system.To sum up, the dissertation shows that the comparison between the conventional reefer and the MC illustrates the promising advantages of the MC, then a transient analysis is developed for deeply understanding the behaviors of the system component parameters, which leads finally to improvements in the system to enhance its performance.
ContributorsSyam, Mahmmoud Muhammed (Author) / Phelan, Patrick (Thesis advisor) / Villalobos, Rene (Thesis advisor) / Huang, Huei-Ping (Committee member) / Bocanegra, Luis (Committee member) / Al Omari, Salah (Committee member) / Arizona State University (Publisher)
Created2023