Engineering Commons^™

Predicting The Performance Of A Solar Domestic Water Heating System With Evacuated Tube Collectors And Hydronic Radiant Flooring, Kimberly Nicole Hammer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Residential solar thermal system installations have been significantly increasing in the last decade and there exists limited resources for reasonably predicting the performance of those systems. A simulated model is developed in MATLAB® and used to predict the performance of a solar domestic water heating system. In the simulated system, hot water is generated using evacuated tube solar collectors and stored in a domestic hot water storage tank, which utilizes immersed coil heat exchangers. The system is designed to provide hydronic radiant floor heating to its occupants based on the heat loss of a building energy model for an energy-efficient …

Floatovoltaics: Quantifying The Benefits Of A Hydro-Solar Power Fusion, Abe Mckay

Pomona Senior Theses

To slow climate change, humans should take immediate and widespread action. One way to slow climate change is by switching to switch to renewable power plants such as solar fields. Recently, pioneering companies have built solar fields on water bodies. This study found that such a pairing of water and solar could increase production efficiency by 8-10% through panel cooling, save millions of liters of water from evaporation, and produce energy with under-utilized space.

Investigation Of Peak Load Reduction Strategies In Residential Buildings In Cooling Dominated Climates, Fady Atallah

UNLV Theses, Dissertations, Professional Papers, and Capstones

This investigation of peak load reduction strategies in residential buildings contributes to the global international efforts in reducing energy consumption and is related directly to energy efficiency in residential and commercial buildings. Work reported here involves computer aided building energy simulation of energy efficient and non-energy efficient residential homes coupled with empirical energy consumption data gathered from monitoring an array of energy efficient residential homes. The latter have been implemented for peak load reduction strategies. In addition non-energy efficient residential homes have been monitored to compare performance to the energy efficient homes. This study demonstrates the crucial importance of energy …

Investigating The Feasibility Of Growing Algae For Fuel In Southern Nevada, Faegheh Moazeni

UNLV Theses, Dissertations, Professional Papers, and Capstones

Microalgae capable of growing in waste are adequate to be mass-cultivated for biodiesel, avoiding fertilizers and clean water, two obstacles to sustainability of the feedstock production. This study replaces fertilizers and clean water with waste products. The investigated wastes include (1) the liquid fraction of sewage after solids and particles are removed, known as centrate, and (2) algal biomass residue, i.e. the algae remaining at the end of the lipids extraction process at biofuel plants. These wastes contain sufficient amount of nitrogen and phosphorus required for algal growth. This study proposes a system in which centrate would be used as …

Sustainable Urban Rail Trails: Designing The Cross Kirkland Corridor, Mia Cooledge

Scripps Senior Theses

This thesis is a guide to building a sustainable rail-trail, wherein I focus on invasive species removal, green pavement, and creating an inviting space with the inclusion of integrated art. When the City of Kirkland, WA purchased the 5.75 mile long section of railroad going through the city, I approached city manager Kurt Triplett to ask about his plans for the corridor. He liked the idea of aiming for a sustainable trail, so I wrote a guide to building an environmentally friendly trail based on a number of prominent readings on sustainable design.

Greening The Streets: A Comparison Of Sustainable Stormwater Management In Portland, Oregon And Los Angeles, California, Na'ama Schweitzer

Pomona Senior Theses

Stormwater runoff is one of the main sources of pollution for urban waterways. Stormwater has traditionally been managed through concrete-based storm drainage systems, but the past twenty years have introduced an alternative in the form of green infrastructure. Green infrastructure for stormwater management involves the use of low impact development (LID), often vegetated facilities to mimic natural hydrologic systems that capture and allow infiltration of rainwater where it falls and from impervious surfaces upstream, before entering the drainage system. Portland, Oregon and Los Angeles, California have adopted green infrastructure into their stormwater management plans. For this project, bioswales, a form …

Evaluating Alternatives For Augmented Water Quality Improvement Utilizing Oyster Restoration As Best Management Practice (Bmp), Stephanie Roberts Long

Civil & Environmental Engineering Theses & Dissertations

Due to several anthropogenic influences, the Chesapeake Bay has experienced a marked decrease in water quality since the colonists arrived at the Jamestown settlement in Virginia during the 1600s. Higher concentrations of nitrogen and phosphorus have enriched the estuaries and coastal waters via point sources (sewage treatment plants and industrial wastes), nonpoint sources (agricultural run-off and septic tank discharges) and the atmosphere (Newell et al., 2005). Restoring oyster beds is considered a Best Management Practice (BMP) to improve water quality as well as provide physical habitat for aquatic species and a healthier estuarine system (USACE Native Oyster Restoration Master …

Csp Desalination/Water Purification Unit, Sean Goodison

Industrial Technology and Packaging

An estimated 3.4 million people die each year from unsanitary water or inaccessible water supply. Most of these deaths take place in the developing, third world (99%). There is a dilemma arising on the world stage as well. The water demand/supply deficit is expected to increase significantly over the next 37 years if preemptive action isn’t taken. 97% of the world water supply is oceanic, making it an attractive solution to the water deficit. Providing autonomous, “deploy and watch” systems for utilizing sustainable energy to provide purified water for unitized low pricing has the potential to penetrate a large world …

Effects Of Molecular Structure Of The Oxidation Products Of Reactive Atmospheric Hydrocarbons On The Formation Of Secondary Organic Particulate Matter, Including The Effects Of Water, Negar Niakan

Dissertations and Theses

Organic aerosols have significant effects on human health, air quality and climate. Secondary organic aerosols (SOA) are produced by the oxidation of primary-volatile organic compounds (VOC). For example, α-pinene reacts with oxidants such as hydroxyl radical (OH), ozone (O₃), and nitrate radical (NO₃), accounting for a significant portion of total organic aerosol in the atmosphere. Experimental studies have shown that the oxidation process between α-pinene and ozone has the most significant impact in the formation of SOA (Hoffmann et al., 1997). Most of the models used to predict SOA formation, however, are limited in that they …

Similarity Of Climate Control On Base Flow And Perennial Stream Density In The Budyko Framework, Liuliu Wu

Electronic Theses and Dissertations

Streams are classified into perennial, intermittent, and ephemeral streams based on flow durations. Perennial stream is the basic network, while intermittent or ephemeral stream is the expanded network. Connection between perennial stream and base flow at the mean annual scale exists since one of the hydrologic functions of perennial stream is to deliver runoff even in low flow seasons. The partitioning of precipitation into runoff and evaporation at the mean annual scale, on the first order, is captured by the ratio of potential evaporation to precipitation (Ep/P called climate aridity index) based on the Budyko hypothesis. The primary focus of …

Mission Aware Energy Saving Strategies For Army Ground Vehicles, Macam Dattathreya

Wayne State University Dissertations

Fuel energy is a basic necessity for this planet and the modern technology to perform many activities on earth. On the other hand, quadrupled automotive vehicle usage by the commercial industry and military has increased fuel consumption. Military readiness of Army ground vehicles is very important for a country to protect its people and resources. Fuel energy is a major requirement for Army ground vehicles. According to a report, a department of defense has spent nearly $13.6 billion on fuel and electricity to conduct ground missions. On the contrary, energy availability on this plant is slowly decreasing. Therefore, saving energy …

Evaluation Of Non-Stationarity In Annual Maximum Flood Series Of Moderately Impaired Watersheds In The Upper Midwest And Northeastern United States, Neila Salvadori

Dissertations, Master's Theses and Master's Reports - Open

United States federal agencies assess flood risk using Bulletin 17B procedures which assume annual maximum flood series are stationary. This represents a significant limitation of current flood frequency models as the flood distribution is thereby assumed to be unaffected by trends or periodicity of atmospheric/climatic variables and/or anthropogenic activities. The validity of this assumption is at the core of this thesis, which aims to improve understanding of the forms and potential causes of non-stationarity in flood series for moderately impaired watersheds in the Upper Midwest and Northeastern US. Prior studies investigated non-stationarity in flood series for unimpaired watersheds; however, as …

An Investigation Of Waste Glass-Based Geopolymers Supplemented With Alumina, Mary U. Christiansen

Dissertations, Master's Theses and Master's Reports - Open

An increased consideration of sustainability throughout society has resulted in a surge of research investigating sustainable alternatives to existing construction materials. A new binder system, called a geopolymer, is being investigated to supplement ordinary portland cement (OPC) concrete, which has come under scrutiny because of the CO2 emissions inherent in its production.

Geopolymers are produced from the alkali activation of a powdered aluminosilicate source by an alkaline solution, which results in a dense three-dimensional matrix of tetrahedrally linked aluminosilicates. Geopolymers have shown great potential as a building construction material, offering similar mechanical and durability properties to OPC. Additionally, geopolymers have …

Stilling Basin Scour Remediation Using Air Injection And Flat Plate Extension, Rachael Barlock

Dissertations, Master's Theses and Master's Reports - Open

The South Florida Water Management District (SFWMD) is responsible for managing over 2500 miles of waterways and hundreds of water control structures. Many of these control structures are experiencing erosion, known as scour, of the sediment downstream of the structure. Laboratory experiments were conducted in order to investigate the effectiveness of two-dimensional air diffusers and plate extensions (without air injection) on a 1/30 scale model of one of SFWMD gated spillway structures, the S65E gated spillway. A literature review examining the results of similar studies was conducted. The experimental design for this research was based off of previous work done …

Ionization In Diesel Combustion For On-Board Diagnostics And Engine Control, Tamer Hassan Badawy

Wayne State University Dissertations

Diesel engines have been known for their high thermal efficiency and specific power output, but there is concern about engine-out NOx and particulate matter emissions. To meet the current emission standards, advanced diesel engines are fitted with electronically controlled fuel injection systems and sophisticated and expensive after-treatment devices. Further improvements are still needed to meet future goals in better fuel economy and the more stringent emission standards. In order to meet these goals, there is a need for the control of the combustion process to reduce engine-out emissions in real-time and reduce the demand on the after-treatment devices. This requires …

Green Diesel Production Via Catalytic Hydrogenation/Decarboxylation Of Triglycerides And Fatty Acids Of Vegetable Oil And Brown Grease, Elvan Sari

Wayne State University Dissertations

Increase in the petroleum prices, projected increases in the world’s energy demand and environmental awareness have shifted the research interest to the alternative fuel technologies. In particular, green diesel, vegetable oil/animal fat/waste oil and grease derived hydrocarbons in diesel boiling range, has become an attractive alternative to biodiesel— a mixture of fatty acid methyl esters, particularly due to its superior fuel properties that are similar to petroleum diesel. Hence, green diesel can be used as a drop-in fuel in the current diesel engines. The current technology for production of green diesel– hydrodeoxygenation of triglycerides and fatty acids over conventional hydrotreating …

Thermal Barrier Coatings (Tbc's) For High Heat Flux Thrust Chambers, Christopher Michael Bradley

Open Access Theses & Dissertations

The last 30 years materials engineers have been under continual pressure to develop materials with a greater temperature potential or to produce configurations that can be effectively cooled or otherwise protected at elevated temperature conditions. Turbines and thrust chambers produce some of the harshest service conditions for materials which lead to the challenges engineers face in order to increase the efficiencies of current technologies due to the energy crisis that the world is facing. The key tasks for the future of gas turbines are to increase overall efficiencies to meet energy demands of a growing world population and reduce the …

Accurate Prediction Of Spectral Phonon Relaxation Time And Thermal Conductivity Of Intrinsic And Perturbed Materials, Tianli Feng

Open Access Theses

The prediction of spectral phonon relaxation time, mean-free-path, and thermal conductivity can provide significant insights into the thermal conductivity of bulk and nanomaterials, which are important for thermal management and thermoelectric applications. We perform frequency-domain normal mode analysis (NMA) on pure bulk argon and pure bulk germanium. Spectral phonon properties, including the phonon dispersion, relaxation time, mean free path, and thermal conductivity of argon and germanium at different temperatures have been calculated. We find the dependence of phonon relaxation time τ on frequency ω and temperature T vary from ~ω^-1.3 to ~ω^-1.8 and ~T^-0.8 to ~T^{-1.8 …}

Climate Change Impacts On Rainfed Corn Production In Malawi, Kondwani Msowoya

Electronic Theses and Dissertations

Agriculture is the mainstay of the economy in Malawi and accounts for 40% of the Gross Domestic Product (GDP) and 90% of the export revenues. Corn (maize) is the major cereal crop grown as staple food under rainfed conditions, covers over 92% of the total agricultural area, and contributes 54% of the caloric intake. Corn production is the principle occupation and major source of income for over 85% of the total population in Malawi. Issues of hunger and food insecurity for the entire nation are associated with corn scarcity and low production. Global warming is expected to cause climate change …

Developing A Group Decision Support System (Gdss) For Decision Making Under Uncertainty, Soroush Mokhtari

Electronic Theses and Dissertations

Multi-Criteria Decision Making (MCDM) problems are often associated with tradeoffs between performances of the available alternative solutions under decision making criteria. These problems become more complex when performances are associated with uncertainty. This study proposes a stochastic MCDM procedure that can handle uncertainty in MCDM problems. The proposed method coverts a stochastic MCDM problem into many deterministic ones through a Monte-Carlo (MC) selection. Each deterministic problem is then solved using a range of MCDM methods and the ranking order of the alternatives is established for each deterministic MCDM. The final ranking of the alternatives can be determined based on winning …

Virtual Interactions With Real-Agents For Sustainable Natural Resource Management, Tyler Pierce

Electronic Theses and Dissertations

Common pool resource management systems are complex to manage due to the absence of a clear understanding of the effects of users’ behavioral characteristics. Non-cooperative decision making based on individual rationality (as opposed to group rationality) and a tendency to free ride due to lack of trust and information about other users’ behavior creates externalities and can lead to tragedy of the commons without intervention by a regulator. Nevertheless, even regulatory institutions often fail to sustain natural common pool resources in the absence of clear understanding of the responses of multiple heterogeneous decision makers to different regulation schemes. While modeling …

Determinants Of Neighborhood Exposure To Extreme Heat: A Spatial Examination Of El Paso And Juárez, 2010, Faraj Mohamad Aboargob

Open Access Theses & Dissertations

Numerous studies have been conducted on the modification of local weather by the urban environment. In studying urban environmental effects on the urban heat island (UHI), researchers have investigated influences such as land use, vegetation density, topography, population density, and neighborhood socioeconomic status. Many studies have used data collected from field observations, while other studies relied solely on computer modeling. This Dissertation research used a spatial analysis approach, which has been less widely employed, to investigate neighborhood level biophysical, built environmental and socio-demographic determinants of the El Paso and Juárez UHI. The research utilized inexpensive data obtained from US and …

Investigation Of The Radiative Heat Release Factor Of Premixed Oxy-Syngas Flames, Martin De La Torre

Open Access Theses & Dissertations

A significant part of the United States is being powered by combustion devises relying on coal since it is abundant and is a high emitting source of electricity per unit energy, however; the burning of this fuel is responsible for a significant contribution for the pollutant emissions causing global warming. Because coal is one of the main sources of energy in the U.S. and around the globe, the scientific community has been investigating ways to meet current and future governmental emission requirements. It is now well established that radiating heat from the flame is a major contributor of the heat …

Potential For Electrical Power Generation Using Forest Wood Biomass In Rural Areas Of Catalonia, Arnau Gonzalez

Open Access Theses

Biomass is a renewable energy source that has been used for many years. However, its usage as an electricity source in Spain is not well developed due to many causes, among which highlights the lack of knowledge about the available technical potential. This research sought to close this gap assessing the technical potential for electricity generation using forest wood biomass in rural areas of Catalonia. The study characterizes the amount and type of biomass available in Catalonian forests that can be used to produce electricity without going beyond the capacity of regeneration of the forest, as well as the state-of-the-art …

Synthetic Asphaltene As A Novel Dye In Dye Sensitized Solar Cells Dsscs, Hassan Sharif

Open Access Theses & Dissertations

This dissertation approves the possibility of the first time use of synthetic asphaltene as new dye in dye sensitized solar cells. In which the conversion efficiency of synthetic asphaltene DSSC has improved up to 2.0 %. Synthetic asphaltene sample was prepared from the starting material as in literature and applied for various solar cell parameters of TiO2 based dyesensitized solar cell DSSC. DSSCs were fabricated using the synthetic asphaltene as dye. Different variables and parameters were carried out to test the photovoltaic performance of the cells, these parameters include open-circuit voltage, short-circuit current; fill factor. The first result was obtained …

Pressure And Heat Flux Effects On The Heat Transfer Characteristics Of Liquid Methane, Chance Paul Garcia

Open Access Theses & Dissertations

The heat transfer effects on liquid methane are investigated with the use of a carbo-thermal rig at the Center for Space Exploration Technology Research (cSETR) located at the University of Texas at El Paso (UTEP). The cSETR carbo-thermal rig design approach is presented along with the design of a methane condensing mobile unit (MCMU) to supply the laboratory and rig with liquid methane. The proposed research will generate useful insight in to heat transfer coefficient behavior, non-dimensional correlations, different flow conditions, varied inlet conditions, and varied heat flux for a subscale test article applicable to a regenerative cooled rocket engine …

An Evaluation Of The Cerro Process As An Efficient Ro Concentrate Management System, Guillermo Guadalupe Delgado

Open Access Theses & Dissertations

The Concentrate Enhanced Recovery Reverse Osmosis (CERRO) Process is a new method to treat RO concentrate and brackish water with high concentrations of silica and calcium sulfate. Prior investigations have shown that the CERRO process can treat this kind of water without fouling or scaling the membranes, but the main factors that allow the system to operate in such conditions were not studied. The research presented here is an evaluation of the CERRO process as an efficient RO concentrate management system. The parameters of operation of the system were evaluated and improved. The precipitation of calcium sulfate was identified as …

Hydromorphology Of The Econlockhatchee River, John Baker

Electronic Theses and Dissertations

Climate change and human activities alter the hydrologic systems and exerted global scale impacts on our environment with significant implications for water resources. Climate change can be characterized by the change of precipitation and temperature, and both precipitation pattern change and global warming are associated with the increase in frequency of flooding or drought and low flows. With increasing water demand from domestic, agricultural, commercial, and industrial sectors, humans are increasingly becoming a significant component of the hydrologic cycle. Human activities have transformed hydrologic processes at spatial scales ranging from local to global. Human activities affecting watershed hydrology include land …

Economic Valuation Of Florida Sea Turtles In Face Of Sea Level Rise, Ahmed Hamed

Electronic Theses and Dissertations

Sea level rise (SLR) is posing a great risk of flooding and inundation to coastal areas in Florida. Some coastal nesting species, including sea turtle species, have experienced diminished habitat from SLR. In an effort to assess the economic and ecosystem service loss to coastal areas with respect to sea turtles Contingent Valuation Method (CVM) and Habitat Equivalency Analysis (HEA) were used. The CVM was used to measure the economic impacts of SLR on sea turtles. Open-ended and dichotomous choice CVM was used to obtain the willingness to pay (WTP) values of Florida residents to implement certain mitigation strategies which …

Investigation Of Wastewater Treatment Plant Sustainability Potential In Terms Of Resource Recovery Essentials, Aoife Moloney

Theses

This thesis aims to explore the sustainability potential which exists in Wastewater Treatment Plants (WWTP's); particularly focusing on nutrient, energy, and water recovery and reuse. The core of the research will focus on the establishment of a sustainable Resource Recovery Treatment Plant (RRTP) plan for Limerick Main Drainage (LMD) WWTP, and potentially utilising this as a case study plant which could act as a foundation example within the sector.

There is a genuine need to investigate more sustainable options in wastewater treatment (WWT); increasing energy and sludge management costs are a real issue for non-sustainable WWTP's given that thousands of …