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A novel concept for integration of flame-assisted fuel cells (FFC) with a gas turbine is analyzed in this paper. Six different fuels (CH4, C3H8, JP-4, JP-5, JP-10(L), and H2) are investigated for the analytical model of the FFC integrated gas turbine hybrid system. As equivalence ratio increases, the efficiency of

A novel concept for integration of flame-assisted fuel cells (FFC) with a gas turbine is analyzed in this paper. Six different fuels (CH4, C3H8, JP-4, JP-5, JP-10(L), and H2) are investigated for the analytical model of the FFC integrated gas turbine hybrid system. As equivalence ratio increases, the efficiency of the hybrid system increases initially then decreases because the decreasing flow rate of air begins to outweigh the increasing hydrogen concentration. This occurs at an equivalence ratio of 2 for CH4. The thermodynamic cycle is analyzed using a temperature entropy diagram and a pressure volume diagram. These thermodynamic diagrams show as equivalence ratio increases, the power generated by the turbine in the hybrid setup decreases. Thermodynamic analysis was performed to verify that energy is conserved and the total chemical energy going into the system was equal to the heat rejected by the system plus the power generated by the system. Of the six fuels, the hybrid system performs best with H2 as the fuel. The electrical efficiency with H2 is predicted to be 27%, CH4 is 24%, C3H8 is 22%, JP-4 is 21%, JP-5 is 20%, and JP-10(L) is 20%. When H2 fuel is used, the overall integrated system is predicted to be 24.5% more efficient than the standard gas turbine system. The integrated system is predicted to be 23.0% more efficient with CH4, 21.9% more efficient with C3H8, 22.7% more efficient with JP-4, 21.3% more efficient with JP-5, and 20.8% more efficient with JP-10(L). The sensitivity of the model is investigated using various fuel utilizations. When CH4 fuel is used, the integrated system is predicted to be 22.7% more efficient with a fuel utilization efficiency of 90% compared to that of 30%.

ContributorsRupiper, Lauren Nicole (Author) / Milcarek, Ryan (Thesis director) / Wang, Liping (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / School for Engineering of Matter,Transport & Enrgy (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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In the last several years, there has been a significant growth in research in the field of power harvesting, the process of capturing the energy surrounding a system and converting it into usable electrical energy. This concept has received particular interest in recent years with the ever-increasing production of portable

In the last several years, there has been a significant growth in research in the field of power harvesting, the process of capturing the energy surrounding a system and converting it into usable electrical energy. This concept has received particular interest in recent years with the ever-increasing production of portable and wireless electronic devices. Many of these devices that are currently in production utilize electrochemical batteries as a power source, which while effective, maintain the drawback of having a finite energy supply, thus requiring periodic replacement. The concept of power harvesting, however, works to solve these issues through electronics that are designed to capture ambient energy surrounding them convert it into usable electronic energy. The use of power harvesting in energy scavenging devices allows for the possible development of devices that are self-powered and do not require their power sources to be replaced. Several models have been developed by Soldano et al [3] and Liao et al [2] that have been proven accurate at predicting the power output of a piezoelectric power harvester in a cantileaver beam configuration. The work in this paper will expand further on the model developed by Liao et al [2], and as its main goal will use a modified form of that model to predict the optimal dimensions for a beam power harvester to achieve the maximum power output possible. The model will be updated b replacing the mode shape function used to approximate the deflection of the beam with the true defletion, which is based on the complex wavenumber that incorporates the complex Young's modulus of the material used. Other changes to account for this replacement will also be presented, along with numerical results of the final model.
ContributorsWinterstein, Joshua (Author) / Liao, Yabin (Thesis director) / Jiang, Hanqing (Committee member) / Chen, Kangping (Committee member) / Barrett, The Honors College (Contributor)
Created2012-05
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The following document addresses two grand challenges posed to engineers: to make solar energy economically viable and to restore and improve urban infrastructure. Design solutions to these problems consist of the preliminary designs of two energy systems: a Packaged Photovoltaic (PPV) energy system and a natural gas based Modular Micro

The following document addresses two grand challenges posed to engineers: to make solar energy economically viable and to restore and improve urban infrastructure. Design solutions to these problems consist of the preliminary designs of two energy systems: a Packaged Photovoltaic (PPV) energy system and a natural gas based Modular Micro Combined Cycle (MMCC) with 3D renderings. Defining requirements and problem-solving approach methodology for generating complex design solutions required iterative design and a thorough understanding of industry practices and market trends. This paper briefly discusses design specifics; however, the major emphasis is on aspects pertaining to economical manufacture, deployment, and subsequent suitability to address the aforementioned challenges. The selection of these systems is based on the steady reduction of PV installation costs in recent years (average among utility, commercial, and residential down 27% from Q4 2012 to Q4 2013) and the dramatic decline in natural gas prices to $5.61 per thousand cubic feet. In addition, a large number of utility scale coal-based power plants will be retired in 2014, many due to progressive emission criteria, creating a demand for additional power systems to offset the capacity loss and to increase generating capacity in order to facilitate the ever-expanding world population. The proposed energy systems are not designed to provide power to the masses through a central location. Rather, they are intended to provide economical, reliable, and high quality power to remote locations and decentralized power to community-based grids. These energy systems are designed as a means of transforming and supporting the current infrastructure through distributed electricity generation.
ContributorsSandoval, Benjamin Mark (Author) / Bryan, Harvey (Thesis director) / Fonseca, Ernesto (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05
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The two central goals of this project were 1) to develop a testing method utilizing coatings on ultra-thin stainless steel to measure the thermal conductivity (k) of battery electrode materials and composites, and 2) to measure and compare the thermal conductivities of lithium iron phosphate (LiFePO4, "LFP") in industry-standard graphite/LFP

The two central goals of this project were 1) to develop a testing method utilizing coatings on ultra-thin stainless steel to measure the thermal conductivity (k) of battery electrode materials and composites, and 2) to measure and compare the thermal conductivities of lithium iron phosphate (LiFePO4, "LFP") in industry-standard graphite/LFP mixtures as well as graphene/LFP mixtures and a synthesized graphene/LFP nanocomposite. Graphene synthesis was attempted before purchasing graphene materials, and further exploration of graphene synthesis is recommended due to limitations in purchased product quality. While it was determined after extensive experimentation that the graphene/LFP nanocomposite could not be successfully synthesized according to current literature information, a mixed composite of graphene/LFP was successfully tested and found to have k = 0.23 W/m*K. This result provides a starting point for further thermal testing method development and k optimization in Li-ion battery electrode nanocomposites.
ContributorsStehlik, Daniel Wesley (Author) / Chan, Candace K. (Thesis director) / Dai, Lenore (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2014-05
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Currently, approximately 40% of the world’s electricity is generated from coal and coal power plants are one of the major sources of greenhouse gases accounting for a third of all CO2 emissions. The Integrated Gasification Combined Cycle (IGCC) has been shown to provide an increase in plant efficiency compared

Currently, approximately 40% of the world’s electricity is generated from coal and coal power plants are one of the major sources of greenhouse gases accounting for a third of all CO2 emissions. The Integrated Gasification Combined Cycle (IGCC) has been shown to provide an increase in plant efficiency compared to traditional coal-based power generation processes resulting in a reduction of greenhouse gas emissions. The goal of this project was to analyze the performance of a new SNDC ceramic-carbonate dual-phase membrane for CO2 separation. The chemical formula for the SNDC-carbonate membrane was Sm0.075Nd0.075Ce0.85O1.925. This project also focused on the use of this membrane for pre-combustion CO2 capture coupled with a water gas shift (WGS) reaction for a 1000 MW power plant. The addition of this membrane to the traditional IGCC process provides a purer H2 stream for combustion in the gas turbine and results in lower operating costs and increased efficiencies for the plant. At 900 °C the CO2 flux and permeance of the SNDC-carbonate membrane were 0.65 mL/cm2•min and 1.0×10-7 mol/m2•s•Pa, respectively. Detailed in this report are the following: background regarding CO2 separation membranes and IGCC power plants, SNDC tubular membrane preparation and characterization, IGCC with membrane reactor plant design, process heat and mass balance, and plant cost estimations.
ContributorsDunteman, Nicholas Powell (Author) / Lin, Jerry (Thesis director) / Dong, Xueliang (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor) / School of Sustainability (Contributor)
Created2014-05
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The recovery of biofuels permits renewable alternatives to present day fossil fuels that cause devastating effects on the planet. Pervaporation is a separation process that shows promise for the separation of ethanol from biologically fermentation broths. The performance of thin film composite membranes of polydimethylsiloxane (PDMS) and zeolite imidazolate frameworks

The recovery of biofuels permits renewable alternatives to present day fossil fuels that cause devastating effects on the planet. Pervaporation is a separation process that shows promise for the separation of ethanol from biologically fermentation broths. The performance of thin film composite membranes of polydimethylsiloxane (PDMS) and zeolite imidazolate frameworks (ZIF-71) dip coated onto a porous substrate are analyzed. Pervaporation performance factors of flux, separation factor and selectivity are measured for varying ZIF-71 loadings of pure PDMS, 5 wt%, 12.5 wt% and 25 wt% at 60 oC with a 2 wt% ethanol/water feed. The increase in ZIF-71 loadings increased the performance of PDMS to produce higher flux, higher separation factor and high selectivity than pure polymeric films.
ContributorsLau, Ching Yan (Author) / Lind, Mary Laura (Thesis director) / Durgun, Pinar Cay (Committee member) / Lively, Ryan (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / Chemical Engineering Program (Contributor)
Created2014-05
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There are three known materials that readily undergo fission, allowing their use as a base for nuclear fuel: uranium-235, a naturally-occurring but uncommon isotope; plutonium, created from irradiated natural uranium; and uranium-233, produced from thorium. Of the three, uranium-235 and plutonium feature heavily in the modern nuclear industry, while uranium-233

There are three known materials that readily undergo fission, allowing their use as a base for nuclear fuel: uranium-235, a naturally-occurring but uncommon isotope; plutonium, created from irradiated natural uranium; and uranium-233, produced from thorium. Of the three, uranium-235 and plutonium feature heavily in the modern nuclear industry, while uranium-233 and the thorium fuel cycle have failed to have significant presence in the field. Historically, nuclear energy development in the United States, and thorium development in particular, has been tied to the predominant societal outlook on the field, and thorium was only pursued seriously as an option during a period when nuclear energy was heavily favored, and resources seemed scarce. Recently, thorium-based energy has been experiencing a revival in interest in response to pollution concerns regarding fossil fuels. While public opinion is still wary of uranium, thorium-based designs could reduce reliance on fossil fuels while avoiding traditional drawbacks of nuclear energy. The thorium fuel cycle is more protected against proliferation, but is also much more expensive than the uranium-plutonium cycle in a typical reactor setup. Liquid-fueled molten salt reactor designs, however, bypass the prohibitive expense of U-233 refabrication by avoiding the stage entirely, keeping the chain reaction running with nothing but thorium input required. MSRs can use any fissile material as fuel, and are relatively safe to operate, due to passive features inherent to the design.
ContributorsGalbiati, Joseph Nicco (Author) / Martin, Thomas (Thesis director) / Foy, Joseph (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor)
Created2014-05
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The global energy demand is expected to grow significantly in the next several decades and support for energy generation with high carbon emissions is continuing to decline. Alternative methods have gained interest, and wind energy has established itself as a viable source. Standard wind farms have limited room for growth

The global energy demand is expected to grow significantly in the next several decades and support for energy generation with high carbon emissions is continuing to decline. Alternative methods have gained interest, and wind energy has established itself as a viable source. Standard wind farms have limited room for growth and improvement, so wind energy has started to explore different directions. The urban environment is a potential direction for wind energy due to its proximity to the bulk of energy demand. CFD analysis has demonstrated that the presence of buildings can accelerate wind speeds between buildings and on rooftops. However, buildings generate areas of increased turbulence at their surface. The turbulence thickness and intensity vary with roof shape, building height, and building orientation. The analysis has concluded that good wind resource is possible in the urban environment in specific locations. With that, turbine selection becomes very important. A comparison has concluded that vertical axis wind turbines are more useful in the urban environment than horizontal axis wind turbines. Furthermore, building-augmented wind turbines are recommended because they are architecturally integrated into a building for the specific purpose of generating more energy. The research has concluded that large-scale generation in the urban environment is unlikely to be successful, but small-scale generation is quite viable. Continued research and investigation on urban wind energy is recommended.
ContributorsKlumpers, Ryan Scott (Author) / Calhoun, Ronald (Thesis director) / Huang, Huei-Ping (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05
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The goal of this research was to identify why the federal government should invest in solar research and development, and which areas of solar improvement should be focused on. Motivation for this can be found in the pressing need to prevent and reverse the effects of climate change, the inevitability

The goal of this research was to identify why the federal government should invest in solar research and development, and which areas of solar improvement should be focused on. Motivation for this can be found in the pressing need to prevent and reverse the effects of climate change, the inevitability of fossil fuel resources eventually running out, and the economic and job creation potential which solar energy holds. Additionally, it is important to note that the best course of action will involve a split of funding between current solar rollout and energy grid updating, and the R&D listed in this research. Upon examination, it can be seen that an energy revolution, led by a federal solar jobs program and a Green New Deal, would be both an ethically and economically beneficial solution. A transition from existing fossil fuel infrastructure to renewable, solar-powered infrastructure would not only be possible but highly beneficial in many aspects, including massive job creation, a more affordable, renewable energy solution to replace coal-fired plants, and no fuel spending or negotiation required.<br/>When examining which areas of solar improvement to focus on for R&D funding, four primary areas were identified, with solutions presented for each. These areas for improvement are EM capture, EM conversion efficiency, energy storage capacity, and the prevention of overheating. For each of these areas of improvement, affordable solutions that would greatly improve the efficiency and viability of solar as a primary energy source were identified. The most notable area that should be examined is solar storage, which would allow solar PV panels to overcome their greatest real and perceived obstacle, which is the inconsistent power generation. Solar storage is easily attainable, and with enough storage capacity, excess solar energy which would otherwise be wasted during the day can be stored and used during the night or cloudy weather as necessary. Furthermore, the implementation of highly innovative solutions, such as agrivoltaics, would allow for a solar revolution to occur.

ContributorsWhitlow, Hunter Marshall (Author) / Fong, Benjamin (Thesis director) / Andino, Jean (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Membrane-based technology for gas separations is currently at an emerging stage of advancement and adoption for environmental and industrial applications due to its substantial advantages like lower energy and operating costs over the conventional gas separation technologies. Unfortunately, the available polymeric (or organic) membranes suffer a trade-off between permeance and

Membrane-based technology for gas separations is currently at an emerging stage of advancement and adoption for environmental and industrial applications due to its substantial advantages like lower energy and operating costs over the conventional gas separation technologies. Unfortunately, the available polymeric (or organic) membranes suffer a trade-off between permeance and selectivity. Mixed matrix membranes (MMMs) containing two-dimensional (2D) metal-organic frameworks (MOFs) as fillers are a highly sought approach to redress this trade-off given their enhanced gas permeabilities and selectivities compared to the pure polymeric membrane. These MMMs are increasingly gaining attention by researchers due to their unique properties and wide small- and large-scale gas separation applications. However, straightforward and scalable methods for the synthesis of MOFs nanosheets have thus far been persistently elusive. This study reports the single-phase preparation, and characterization of MMMs with 2D MOFs nanosheets as fillers. The prepared MOF and the polymer matrix form the ‘dense’ MMMs which exhibit increased gas diffusion resistance, and thus improved separation abilities. The single-phase approach was more successful than the bi-phase at synthesizing the MOFs. The influence of sonication power and time on the characteristics and performance of the membranes are examined and discussed. Increasing the sonication power from 50% to 100% reduces the pore size. Additionally, the ultimate effect on the selectivity and permeance of the MMMs with different single gases is reported. Analysis of results with various gas mixers indicates further performance improvements in these MMMs could be achieved by increasing sonication time and tuning suitable membrane thicknesses. Reported results reveal that MMMs are excellent candidates for next-generation gas mixture separations, with potential applications in CO2 capture and storage, hydrogen recovery, alkene recovery from alkanes, and natural gas purification.
ContributorsNkuutu, John (Author) / Mu, Bin (Thesis director) / Shan, Bohan (Committee member) / Chemical Engineering Program (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05