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Design Of Wind Turbine Tower Height And Blade Length: An Optimization Approach, Ryan Wass 2018 University of Arkansas, Fayetteville

Design Of Wind Turbine Tower Height And Blade Length: An Optimization Approach, Ryan Wass

Mechanical Engineering Undergraduate Honors Theses

The wind industry is a fast growing market and is quickly becoming competitive with traditional non-renewable energy resources. As with any developing industry, research must continually be redefined as more complex understandings of design variables are learned. Optimization studies are common ways to quickly refine design variable selections. Historical wind turbine data shows that the tower hub height to rotor diameter ratio scales almost linearly. However there is no specific rule that dictates the optimum hub height for a given diameter. This study addresses this question by using an Excel based optimization program to determine the height to diameter ratio ...


Waste Heat Recovery From A Vented Electric Clothes Dryer Utilizing A Finned-Tube Heat Exchanger, Abdul Raheem A. Shaik, Stephen L. Caskey, Eckhard A. Groll 2018 Purdue University

Waste Heat Recovery From A Vented Electric Clothes Dryer Utilizing A Finned-Tube Heat Exchanger, Abdul Raheem A. Shaik, Stephen L. Caskey, Eckhard A. Groll

The Summer Undergraduate Research Fellowship (SURF) Symposium

Conventional residential clothes dryers continuously vent moist, hot air during the drying process. The vented air leaves the home but still has useful temperature and humidity that could be recovered to offset other heating demands in the home. A study is carried out to quantify the amount of heat extracted from the waste heat stream of a conventional, vented clothes dryer. To extract the heat, a water cooled, fin-and-tube heat exchanger is located within the exhaust duct. A steady state thermodynamic dry coil and wet coil model was built in Engineering Equation Solver (EES). The model accounts for the heat ...


A Swing Generator Using Water Power Produced By The Wind, Ruka Ozaki 2018 Tokyo Tech High School of Science and Technology

A Swing Generator Using Water Power Produced By The Wind, Ruka Ozaki

The International Student Science Fair 2018

I focus on various kinds of natural energy sources, especially wind. Wind power generation is the most-used method of electricity generation using wind power. Wind power generation has many merits; it achieves high efficiency of electric power generation, it can generate electricity even during the night, it doesn’t make any hazardous materials. However, there are not only merits but also demerits. It can cause bird strike, environment disruption from noise and low-frequency wave. And besides, we must comply building laws when we build wind power generators. Thus I built ‘a swing generator using water power produced by the wind ...


Increased Energy Yield Through Fast Pyrolysis: Empowering Malawian Villages, Diehl Mutamba 2018 Brigham Young University

Increased Energy Yield Through Fast Pyrolysis: Empowering Malawian Villages, Diehl Mutamba

Undergraduate Honors Theses

Biomass contributes to several renewable energy technologies. This project will explore the use of fast pyrolysis to produce fuels by designing an apparatus for fast pyrolysis. Malawian people harvest firewood from the forests, which is a major contributor to deforestation. Furthermore, they convert some of it to charcoal with about 10-15% efficiency to sell to city dwellers. The project will enable herbaceous fuels to replace wood, increase charcoal yields and create new products. Firewood and charcoal produce smoke and carbon monoxide (CO) that compromises the villagers’ health.

This project will address deforestation problems, improve sustainability, decrease health hazards and improve ...


Analysis Of The Properties Of Supercapacitors And Possible Applications For The Technology, Vincent Oliveto 2018 Union College

Analysis Of The Properties Of Supercapacitors And Possible Applications For The Technology, Vincent Oliveto

Honors Theses

Supercapacitors have a lot of excellent qualities that would make them a great substitute for batteries when it comes to electrical energy storage systems. Supercapacitors can discharge and charge very rapidly, they have a lifespan in the realm of millions of cycles, and they are much more efficient than batteries. Unfortunately, they cannot hold nearly as much charge as batteries. This paper seeks to further investigate the properties of supercapacitor technology and the best way to exploit these properties with the purpose of integrating them into renewable energy systems. There is currently a lot of research occurring around the world ...


Applications Of Latent Heat Storage Using Phase Change Materials, Daniel Giroux 2018 Union College

Applications Of Latent Heat Storage Using Phase Change Materials, Daniel Giroux

Honors Theses

Thermal Storage Systems are gaining more attention in recent years with the increased emphasis on more renewable energy sources. Energy storage is necessary whenever there is greater amounts of energy being produced than is required. Various improvements to the conventional heat storage system can be made by integrating latent heat storage into the conventional heat storage system. Latent heat storage can be utilized for thermal storage applications by using phase change materials, materials that will undergo a change in their physical state in the temperature range desired for heat storage.

Analysis was conducted on four different waxes considering the waxes ...


Universal Micro-Hydroelectric Generator, Luke McLaughlin, Owen Bensel, Damon Unland 2018 University of Wyoming

Universal Micro-Hydroelectric Generator, Luke Mclaughlin, Owen Bensel, Damon Unland

Honors Theses AY 17/18

As the demand for electricity continues to grow around the world, so does the ability to provide electricity. However, a significant portion of the global population is still without reliable electricity or any electricity at all. Inconsistent grid power caused by natural disaster, prohibitively expensive utility costs and isolation from grid access are a few factors preventing many people around the world from having access to reliable electricity. These issues can often be addressed through simple solutions such as the implementation of generators and solar panels. But, these solutions can be expensive and present several hurdles such as fuel transportation ...


Fluid Phase Separation Via Nanochannel Array, John Lee 2018 University of Arkansas, Fayetteville

Fluid Phase Separation Via Nanochannel Array, John Lee

Theses and Dissertations

Microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS) generate ideas and techniques for creating new devices at the micro/nano scale. This dissertation study designed a gas generator system utilizing nanochannels for phase separation that is useful for micro-pneumatic actuators, micro-valves, and micro-pumps. The new gas generator has the potential to be an integral part of a propulsion system for small-scale satellites. Nano/picosatellites have limited orientation capability partly due to the current limitations of microthruster devices. Development of a self-contained micro propulsion system enables dynamic orbital maneuvering of pico- and nano-class satellites.

Additionally, the new gas generator utilizes a high ...


Non-Covalent Functionalization Of Graphene Films For Uniform Nanoparticle Deposition Via Atoic Layer Deposition, Ty Seiwert 2018 University of Arkansas, Fayetteville

Non-Covalent Functionalization Of Graphene Films For Uniform Nanoparticle Deposition Via Atoic Layer Deposition, Ty Seiwert

Mechanical Engineering Undergraduate Honors Theses

Graphene functionalized with platinum (Pt) and palladium (Pd) has proven to be highly effective as a hydrogen sensor. Deposition methods such as Atomic layer deposition (ALD) can be further enhanced by pretreating the graphene with a non-covalent surfactant prior to nanoparticle deposition. In this study, graphene-based sensing devices will be fabricated by ALD deposition. The graphene will be non-covalently functionalized using sodium dodecyl sulfate (SDS) anionic surfactant prior to ALD deposition. The aim of this study is to test the deposition pattern achieved by varying the amount of time that graphene is treated with the SDS surfactant. Initially, ALD deposition ...


A Human Powered Micro-Generator For Charging Electronic Devices, John Adam 2018 Linfield College

A Human Powered Micro-Generator For Charging Electronic Devices, John Adam

Senior Theses

A hand-pulled generator has been designed and tested. A preliminary result has been obtained and discussed. This device was created to provide outlet-free charging. Electronic devices are useful when going out into the wilderness. A portable power supply is necessary to keep an electronic device alive. This project created a device that converts human energy into electricity to charge electronic devices. This thesis overviews the device’s design, build, and tests. Two different tests were run to determine that the device is capable of charging the storage battery. The device presented can provide 14 minutes of charging time with one ...


The Effects Of Surface Pace In Baseball, Jason Farlow 2018 Linfield College

The Effects Of Surface Pace In Baseball, Jason Farlow

Senior Theses

A baseball travels across different surfaces at different paces. The goal of this experiment is to find a percentage difference in speeds the ball will reflect off a given surface. The energy lost on the turf surface was far more significant than on dirt surface as the turf lost an average of 26% of its energy as compared to just 16% of the energy on dirt. In the Northwest conference, teams play on four turf-based infields and five dirt-based infields. The results of this study suggest that kinetic friction forces are more significant in reducing ball rebound speed than in ...


Measuring The Double Layer Capacitance Of Electrolyte Solutions Using A Graphene Field Effect Transistor, Agatha Ulibarri 2018 Linfield College

Measuring The Double Layer Capacitance Of Electrolyte Solutions Using A Graphene Field Effect Transistor, Agatha Ulibarri

Senior Theses

When operating graphene field effect transistors (GFETs) in fluid, a double layer capacitance (Cdl) is formed at the surface. In the literature, the Cdl is estimated using values obtained using metal electrode experiments. Due to the distinctive electronic and surface properties of graphene, there is reason to believe these estimates are inadequate. This work seeks to directly characterize the double layer capacitance of a GFET. A unique method for determining the Cdl has been implemented, and data has been obtained for three electrolytes and one ionic fluid. The results yield dramatically lower Cdl values than those ...


Uncertainty In Optical Particulate Counting Sensors, Jared Todd Blanchard 2018 Brigham Young University

Uncertainty In Optical Particulate Counting Sensors, Jared Todd Blanchard

Undergraduate Honors Theses

To mitigate the health problems and environmental damage caused by the burning of biomass in homes across the developing world, there is an international effort to design clean burning cookstoves that burn with greater efficiency and emit fewer harmful substances. An important tool for gauging the effectiveness of these alternate stoves is the optical particulate counting (OPC) sensor, which comes in many varieties. To facilitate comparison between measurements from different models, a mathematical model and uncertainty analysis method for OPC’s have been developed. These may be applied to any light-scattering OPC. In addition, a low-cost physical system was developed ...


Investigating Different Modeling Techniques For Quantifying Heat Transfer Through Building Envelopes, Sodiq Akande 2018 East Tennessee State University

Investigating Different Modeling Techniques For Quantifying Heat Transfer Through Building Envelopes, Sodiq Akande

Appalachian Student Research Forum

There is interest concerning the energy performance of buildings in the United States. Buildings, whether residential, commercial or institutional, generally underperform in terms of energy efficiency when compared to buildings that are constructed following sustainably and energy efficiency standards. A substantial percentage of energy loss in these buildings is associated with the thermal efficiency of its envelope (exterior walls, windows roof, floors and doors). The objective of this study will evaluate the results of three energy modeling techniques developed to investigate the energy transfer through the envelope of existing campus buildings. The techniques employed are solving the heat transfer calculations ...


Multicomponent Working Fluids In Organic Rankine Cycle Evaporators, Jennifer Fromm 2018 Union College

Multicomponent Working Fluids In Organic Rankine Cycle Evaporators, Jennifer Fromm

Honors Theses

Organic Rankine cycles are a promising technology to convert waste heat energy into usable mechanical or electric power, giving them the potential to reduce fossil fuel emissions generated by traditional energy generation. The heat exchangers of these devices are of particular interest, as maximizing energy extraction from these free heat sources will increase net electrical power output. For this project I created a model to predict the effects of mixture working fluids on the evaporator performance of an organic Rankine cycle generator for a wide range of waste heat source temperatures. This model combines empirically derived heat exchanger performance parameters ...


Assessing Spacing Impact On Coherent Features In A Wind Turbine Array Boundary Layer, Naseem Ali, Nicholas Hamilton, Dominic DeLucia, Raúl Bayoán Cal 2018 Portland State University

Assessing Spacing Impact On Coherent Features In A Wind Turbine Array Boundary Layer, Naseem Ali, Nicholas Hamilton, Dominic Delucia, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

As wind farms become larger, the spacing between turbines becomes a significant design consideration that can impose serious economic constraints. To investigate the turbulent flow structures in a 4 x 3 Cartesian wind turbine array boundary layer (WTABL), a wind tunnel experiment was carried out parameterizing the streamwise and spanwise wind turbine spacing. Four cases are chosen spacing turbines by 6 or 3D in the streamwise direction, and 3 or 1:5D in the spanwise direction, where D = 12 cm is the rotor diameter. Data are obtained experimentally using stereo particle image velocimetry. Mean streamwise velocity showed maximum ...


Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed 2018 CUNY City College

Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed

Publications and Research

Centralized communication-based control is one of the main methods that can be implemented to achieve autonomous advanced energy management capabilities in DC microgrids. However, its major limitation is the fact that communication bandwidth and computation resources are limited in practical applications. This can be often improved by avoiding redundant communications and complex computations. In this paper, an autonomous communication-based hybrid state/event driven control scheme is proposed. This control scheme is hierarchical and heuristic, such that on the primary control level, it encompasses state-driven local controllers, and on the secondary control level, an event-driven MG centralized controller (MGCC) is used ...


Investigation On The Potential Of A Co2 Capture System, Downstream Of The Aftertreatment System For A Heavy-Duty Engine Application, Murchana Pathak 2018 Michigan Technological University

Investigation On The Potential Of A Co2 Capture System, Downstream Of The Aftertreatment System For A Heavy-Duty Engine Application, Murchana Pathak

Dissertations, Master's Theses and Master's Reports

The transportation sector accounts for the second largest source of CO2 emissions after power generation. New Corporate Average Fuel Economy (CAFE) regulations are focusing on improving energy through reduced fuel consumption and greenhouse gas emissions. This work investigates the potential of a CO2 capture system downstream of an aftertreatment system for a heavy-duty engine application. Amine absorption has been described as one of the most effective ways to capture CO2 from the exhaust for point sources. Therefore, using thermal-swing absorption process with potassium carbonate (K2CO3) as the absorbent liquid, a process was analyzed for ...


Optimizing Gas-Turbine Operation Using Finite-Element Cfd Modeling, Manoj R. Rajanna, Fen Xu, Ming-Chen Hsu, Yuri Bazilevs, Muthuvel Murugan, Anindya Ghoshal, Luis Bravo 2018 Iowa State University

Optimizing Gas-Turbine Operation Using Finite-Element Cfd Modeling, Manoj R. Rajanna, Fen Xu, Ming-Chen Hsu, Yuri Bazilevs, Muthuvel Murugan, Anindya Ghoshal, Luis Bravo

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Gas turbine engines are generally optimized to operate at nearly a fixed speed with fixed blade geometries for the design operating condition. The performance of gas turbine reduces when operated at different operating condition. In this work, we present a parametric study to optimize gas-turbine performance under off-design conditions by articulating the rotor blades in both clockwise and counterclockwise directions. Articulating the pitch angle of turbine blades in coordination with adjustable nozzle vanes can improve performance by maintaining flow incidence angles within the optimum range at certain off-design conditions. To observe the effect of rotor pitching on the performance of ...


Articulating Axial-Flow Turbomachinery Rotor Blade For Enabling Variable Speed Gas Turbine Engine, Muthuvel Murugan, Anindya Ghoshal, Luis Bravo, Fei Xu, Ming-Chen Hsu, Yuri Bazilevs 2018 United States Army Research Laboratory

Articulating Axial-Flow Turbomachinery Rotor Blade For Enabling Variable Speed Gas Turbine Engine, Muthuvel Murugan, Anindya Ghoshal, Luis Bravo, Fei Xu, Ming-Chen Hsu, Yuri Bazilevs

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Current technology gas turbine engines are generally optimized to operate at nearly a fixed speed with fixed blade geometries for the design operating condition. When the operating condition of the engine changes, the flow incidence angles may not be optimum with the blade geometries resulting in reduced off-design performance. But, if we have the capability of articulating the pitch angle of axial-flow compressor/turbine blades in coordination with adjustable stator vanes, it can improve performance by maintaining flow incidence angles within the optimum range for given blade geometries at all operating conditions. Maintaining flow incidence angles within the optimum range ...


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