Engineering Commons^™

Design And Simulation Analysis Of A Bipv (Building Integrated With Pv) Air-Duct System For Residential High-Performance Development, Arash Zarmehr

Electronic Theses and Dissertations, 2020-2023

A growing number of buildings are integrating building-integrated photovoltaics (BIPV) devices to increase energy efficiency and reduce energy costs. A building's heating and cooling loads are impacted by the thermal resistance of the air duct BIPV because of the change in thermal resistance. Therefore, augmenting the efficiency of (BIPV) devices will benefit many building architectures and mechanical engineering applications. This work introduces a low-cost and low- maintenance air duct system design augmenting BIPV systems. This novel approach increases airflow velocity and decreases air temperature for BIPV, resulting in improved performance for the PV system electricity output, increased PV lifespan due …

Simulating Energy Performance Of Buildings: A Study Using Equest And Energy Star® Portfolio Manager, Sabin Wagle

Graduate Theses, Dissertations, and Problem Reports

The urgent need for improving building energy efficiency in response to global warming and environmental sustainability has highlighted the importance of practical techniques to optimize energy performance. The study utilizes the eQUEST simulation engine and Energy Star® Portfolio Manager to evaluate retrofit and design parameters and conduct a sensitivity analysis to explore the impact of different parameters on building energy performance. The study develops building energy models in eQUEST using data from two fully operational Distribution centers. It is calibrated using the Normalized Mean Bias Error (NMBE) and Coefficient of Variation of Root Mean Square Error (CV(RMSE)) method, meeting the …

Mechanical Energy Harvester For Powering Rfid Systems Components: Modeling, Analysis, Optimization And Design, Alireza Babaei

Theses and Dissertations--Mechanical Engineering

Finding alternative power sources has been an important topic of study worldwide. It is vital to find substitutes for finite fossil fuels. Such substitutes may be termed renewable energy sources and infinite supplies. Such limitless sources are derived from ambient energy like wind energy, solar energy, sea waves energy; on the other hand, smart cities megaprojects have been receiving enormous amounts of funding to transition our lives into smart lives. Smart cities heavily rely on smart devices and electronics, which utilize small amounts of energy to run. Using batteries as the power source for such smart devices imposes environmental and …

System Analysis Of An Internal Combustion Engine (Ice) – Solid Oxide Fuel Cell (Sofc) Hybrid Cycle, Jose Javier Colon Rodriguez

Graduate Theses, Dissertations, and Problem Reports

Due to the intermittent nature of renewable energy and the rigid operation of existing coal plants, the need for flexible power generation technology is eminent. Hybrid energy systems have shown potential for flexible, grid following dynamics while maintaining higher efficiencies. The work below focuses on the performance analysis of a proposed 100 kW pressurized Internal Combustion Engine (ICE) and Solid Oxide Fuel Cell (SOFC) hybrid system. The un-utilized fuel from the SOFC stack provided the chemical energy to operate the engine. A turbocharger was used to deliver the necessary air flow for both the stack and engine. An external reformer …

Evaluating Electrification Of Fossil Fuel-Fired Boilers For Decarbonization Using Discrete Event Simulation, Nahian Ismail Chowdhury

Graduate Theses, Dissertations, and Problem Reports

Decarbonizing fossil fuel usage is crucial in mitigating the impacts of climate change. CO2, which comprises the major portion of greenhouse gas, is emitted from burning fossil fuels. One of the significant sources of fossil fuel user is industrial process heating, and most of the heating in industrial processes is achieved through boilers. Electrification is a promising solution for decarbonizing these boilers, as it enables renewable energy sources to generate electricity, which can then be used to power the electric boilers. The electrification of boilers can reduce greenhouse gas emissions, improve air quality, and increase energy efficiency. However, it requires …

Machine Learning Approach To Investigate Ev Battery Characteristics, Shayan Falahatdoost

Major Papers

The main factor influencing an electric vehicle’s range is its battery. Battery electric vehicles experience driving range reduction in low temperatures. This range reduction results from the heating demand for the cabin and recuperation limits by the braking system. Due to the lack of an internal combustion engine-style heat source, electric vehicles' heating system demands a significant amount of energy. This energy is supplied by the battery and results in driving range reduction. Moreover, Due to the battery's low temperature in cold weather, the charging process through recuperation is limited. This limitation of recuperation is caused by the low reaction …

Development Of A Computationally Efficient Method For Modelling Thermal Energy Storage In Packed Beds Of Spherically Encapsulated Phase Change Material, Colin Jaffray

Electronic Thesis and Dissertation Repository

A novel computationally efficient method for modelling melting and solidification processes in packed beds of PCM encapsulated spheres is introduced. The proposed method involves the full discretization of only one centrally located sphere to fully simulate the phase change process, while treating all other spheres in the packed bed as voids with boundary conditions derived from the simulated sphere. At each time step, the computed heat transfer parameters on the exterior surface of the simulated sphere undergoing the phase change process are extracted, and imposed as boundary conditions on surrounding spheres. The proposed method results in a significant reduction in …

Diffusion-Dependent Electrodes For All-Solid-State Lithium-Ion Batteries, Peiman Mardani

Electronic Thesis and Dissertation Repository

Electrode design, which is closely related to electronic and ionic transport, has a significant impact on all-solid-state batteries' performance. Typically, a combination of the active material and solid electrolyte serves as the electrode for all-solid-state batteries. An effective scaling technique to spatially organize the two components is essential for high-performance all-solid-state batteries. Here, an electrode design for all-solid-state batteries is given with a higher energy density than the typical composite-type electrode. The first section of the thesis presents a simple electrode design that primarily consists of blended active materials of graphite and phosphorus to meet the demands of all-solid-state batteries …

Numerical Study Of Advanced Solar Receiver Tubes Based On A Coupled Thermo-Mechanical Analysis For Concentrated Solar Power Tower Plant, Shawn Michael Hatcher

Theses and Dissertations

The search for more sustainable energy to match the growing energy demand begins with finding more dispatchable resources such as solar energy. As one of the promising solar technologies, concentrated solar power (CSP) has a full capacity to store thermal energy for extended operation. Nevertheless, some key components in CSP systems usually face extreme environment, such as uneven solar flux, cyclic thermal expansion, structural degradation on the solar absorber tubes in a Concentrated Solar Power Tower (CSPT) Plant. In this study, we applied Multiphysics simulation to explore the benefits of introducing optimized fins for heat transfer enhancement and uniform temperature …

Multiscale Investigation Of Freeze Cast Process And Ion Transport For Graphene Aerogel Electrodes, Yu-Kai Weng

Doctoral Dissertations

Effective use of renewable energy resources has been regarded as the most promising solution to climate emergency and energy crisis. However, the fluctuating and intermittent nature of renewable resources causes stability issues in the electric grid. High-capacity electrical energy storage is essential to stabilize the electric power supply using renewable resources. Among various types of energy storage systems, organic redox flow battery (ORFB) has attracted attentions due to their high stability, flexibility, low cost, and environmental compatibility, but the performance of the ORFB still needs a significant improvement due to their low energy or current density. Specifically, even though the …

Gasifier Wall Wash Manifold, Ashley Sieu Che, Gintaras Julius Baipsys, Peyton Joseph Archibald, Michael Thomas Kieran

Mechanical Engineering

The objective of our Gasifier Wall Wash Manifold Project is to design three different manifolds that will uniformly distribute water on the inner diameter of a pressure vessel. Also, the distributed water should completely cover the circumference of the inner walls. From extensive research of current solutions as well as the conduction of technical analyses, we were able to produce three designs that would be able to meet our engineering specifications. Time constraints led to the fabrication of one manifold design along with a test rig. With a fully functional test rig, we saw positive results from our design verification …

Numerical Investigation Of Flow And Thermal Behavior In Channels With Pcm-Filled Thermal Energy Storage Columns For Potential Application In Photobioreactors, Sameed Akber

Electronic Thesis and Dissertation Repository

Microalgae has been identified as a potential source in the production of biofuel. Photobioreactors, which are used for microalgae production, normally experience temperature variations over the diurnal cycle due to changes in ambient conditions. The thermal regulation of photobioreactors to minimize temperature variations will result in a higher yield of microalgae, which are sensitive to such variations. The present research is aimed to investigate a novel approach to thermally regulate photobioreactors using phase change materials (PCM) where the latent heat of the material is exploited as the energy storage. The present research uses a numerical approach to study the flow …

Comparison Of Layered Nickel Cobalt Manganese Oxide Cathodes With Different Compositions And Morphologies In Lithium-Ion Batteries, Fanny Poon

Electronic Thesis and Dissertation Repository

The revolutionary rechargeable lithium-ion battery paves the way for environmentally-friendly applications such as electric vehicles. Nevertheless, further improvements are required to match or exceed the performance of conventional internal combustion engine vehicles, such as higher energy density, faster charging speed, longer lifetime, better safety and lower cost. Lithium layered nickel cobalt manganese oxides (NCM) are a popular choice of cathode material, but they still suffer from problems such as cation mixing, volume changes, microcracking, surface side reactions, high temperature performance issues and structural reconstruction. This thesis compares various NCM materials to figure out what guidelines should be followed to improve …

Enhancing Bifacial Pv Efficiency With The Addition Of A Rear Side Reflector, Neila Watson

Honors Theses

Bifacial photovoltaics are an expanding sector of solar electricity production, collecting solar energy on the front, back, and sides of the module. This increases the efficiency by around 10% to 30% over a typical mono facial cell, which only collects sunlight on the front. However, the performance of bifacial PV arrays depends on a variety of factors, including temperature, shadows, solar insolation, and set-up geometry. The geometry is affected by the tilt angle, the azimuth angle, the height from the ground to the panel, and the reflectance from the ground surface. The addition of a reflector, usually white in color …

Sunsation’S Solar Powered Picnic Table, Michelle M. Barnett, Christopher Barber, Casey Durham, David Mason

Mechanical Engineering

Team SunSation is an interdisciplinary senior design project group that was tasked with developing a semi-permanent seating area for Cal Poly's electrical engineering courtyard. The EE courtyard is populated with plastic folding tables and chairs that are slowly falling apart. Dale Dolan, the head of the EE department, requested that a table design be developed that incorporates the use of solar panels. The addition of the solar panels to the table would help promote clean renewable energy as well as provide shade to those sitting in the courtyard.

The solution that SunSation arrived at is broken up into mechanical/structural, electrical, …

Mmteg Heatsink Design, Peyton Nienaber, Kadin Feldis, Alec Savoye, Jack Waeschle

Mechanical Engineering

In this document, Cal Poly Senior Design Team F16 presents a summary of its work developing a suitable heatsink for Gas Technology Institute’s Methane Mitigation Thermoelectric Generator. After several months of iterating between experimental testing and simulated heat transfer, a suitable prototype was selected for use in further refining simulation parameters. This was called the structural prototype and it allowed Team F16 to confirm several remaining unknowns relating to component thermal conductivity. All documentation of this process can be found in Preliminary, Critical, and Interim Design Review documents (PDR, CDR, IDR), included in this report. Having a realistic model …

Baker/Koob Final Report: Solar Solution For Mini Mars Rover, Jonathan Cederquist, Cole Korchek, Derick Louie, Michaella Ochotorena, Collin Petersen

Mechanical Engineering

This project focused on designing, building, and testing a functional prototype of a collapsible solar array on the mini Mars rover being developed by client and sponsor, Mr. Rich Murray. Although many previous collapsible solar arrays have been deployed for space missions, the previous solar-powered Mars rovers only deployed their arrays once upon landing. This solar array will be able to collapse and deploy multiple times to allow for greater rover mobility and stability when the rover is not charging. This system is critical to the success of the rover project because it provides power without which the rover cannot …

Solid Thermal Storage As An Energy Storage Device In Insulated Solar Electric Cookers: Thermal Modeling And Experiment, Michael Antonio Fernandez

Physics

The use of solid thermal storage (STS) as an energy storage device in insulated solar electric cookers (ISEC) was explored using a thermal simulation before retrofitting an existing cooker without energy storage and testing it under several conditions. STS sizing, material selection, and geometry were examined from both theoretical and practical perspectives and re-examined following experimental results. Characterization of the system’s thermal interfaces and methods to improve their thermal conductivities were investigated resulting in several performance enhancements to the system.

Enhancing Thermoelectric Generator Performance, Xi William Wang

Electronic Theses and Dissertations

Waste heat recovery plays an important role for alleviating the energy crisis and mitigating climate change. The thermoelectrical generator (TEG), a solid energy convertor, is a promising technology. However, the performance of a TEG is sensitive to its geometric structure and working conditions. An improved geometric structure and matching to the working conditions can make a TEG fully utilize its thermoelectrical conversion potential.

The TEG optimization is a kind of combinatorial problem. An effective algorithm is needed to optimize a TEG’s performance. The particle swarm optimization (PSO) algorithm is introduced in this study to optimize a TEG’s output power, efficiency, …

Nuclear Energy As A Reliable And Safe Source Of Power Generation, Sarup Dhungana

Honors Theses

There is a high demand of energy for generating civil applicable power in the world and in the USA, correspondingly. The world has been consuming various sources to extract the power to meet its demands. Most of the power sources include renewable and non-renewable sources like fossil fuels, natural gas, coal, water, solar, wind, and nuclear power. Although most of these sources have many advantages in terms of their capacity and cost of production, nuclear power can be categorized as the emerging driving force in the United States and in the world for power generation, because of its reliability and …

Development And Testing Of A 1:70 Scale Model Wind Turbine Of The Iea Reference 15 Mw Floating Offshore System, Amber Parker

Electronic Theses and Dissertations

This thesis presents the development of a 1/70th scale performance-matched wind turbine intended for wind and wave basin model testing of commercially viable floating wind turbine structures based off of the International Energy Agency (IEA) Wind 15 MW design. The focus of this demonstration is to test active blade pitch response controls and to provide an experimental dataset for use by modelers and industry for future turbine improvements. Future research is planned to test the turbine in conjunction with an actively damping hull to test the interactions between the two control systems.

Outlined in this thesis are the methods of …

Efficient Energy Harvesting With Applications In Vibration And Implantable Biosensors, Mohammad Atmeh

Mechanical Engineering Theses

The world has stepped into the fourth industrial revolution in many ways such as using the internet of things (IoT) in various applications, and removing the rechargeable power sources seeking for batteryless systems. Since energy is widely abundant around us and it is going to waste, numerous of recent studies have been conducted to propose sustainable solutions to harvest the free ambient power from the surrounding and convert it into electricity. Heat energy, kinetic energy, and radio waves are examples of these potentially harvestable energy sources. Mechanical vibrations represent one of the most plentiful forms of kinetic energy that can …

Environmental Design And Optimization Of Modular Hydropower Plants, Colin Sasthav

Doctoral Dissertations

This research aimed to understand the pathways to cost-effective and sustainable low-head hydropower. Designing viable hydropower projects requires optimization across many economic, environmental, and social outcomes. However, existing run-of-river hydropower design models often focus on economic performance and customizing technologies for high-head diversion schemes. Standard modular hydropower is a new design approach that uses standardized rather than custom-designed technologies to achieve economies of scale. Oak Ridge National Laboratory established a conceptual outline for module classes based on functions, such as generation modules and fish passage modules, but further research was needed to identify how modules should be selected and operated …

Enhancing Stability Of High-Nickel Cathodes For Lithium-Ion Batteries Through Additive Manufacturing Of Cathode Structure, Matthew Sullivan

Mechanical Engineering Undergraduate Honors Theses

Lithium-ion batteries (LIBs) are currently the best method to store electrical energy for use in portable electronics and electronic vehicles. New cathode materials for LIBs are consistently studied and researched, but few are as promising and attainable as nickel-rich transition metal oxides such as LiNi1-x-yMnxCoyO2 (NMC). NMC materials exist with many different mass ratios, but higher nickel content materials provide higher energy density. With this increase in capacity comes a sacrifice with cyclability, as high-nickel NMC variants are prone to structure collapse, transition metal dissolution, and cracks due to volume change. In this report, mechanical modification of the electrode by …

Cal Poly Fluid Power Vehicle Challenge 2022, Sangmin Sung, Eddy Rodriguez, Travis Welch, Jeremy Baechler, Kevin Pauls

Mechanical Engineering

In this report, the Featherweight Cycles design team puts forth the scope and overview of their design project, discusses background research and competitor analysis, and presents the project’s final design and manufacturing plans. The overall goal of this project is to fabricate and compete in the Fluid Power Vehicle Challenge, hosted by the National Fluid Power Association. To better define the design process, the team researched previous year’s designs from Cal Poly, as well as winning designs from the last two years to form a baseline of knowledge about competing schools’ designs. After researching multiple design paths, Featherweight Cycles chose …

Nucleate Boiling Under Different Gravity Values: Numerical Simulations & Data-Driven Techniques., Sandipan Banerjee

Electronic Theses and Dissertations

Nucleate boiling is important in nuclear applications and cooling applications under earth gravity conditions. Under reduced gravity or microgravity environment, it is significant too, especially in space exploration applications. Although multiple studies have been performed on nucleate boiling, the effect of gravity on nucleate boiling is not well understood. This dissertation primarily deals with numerical simulations of nucleate boiling using an adaptive Moment-of-Fluid (MoF) method for a single vapor bubble (water vapor or Perfluoro-n-hexane) in saturated liquid for different gravity levels. Results concerning the growth rate of the bubble, specifically the departure diameter and departure time have been provided. The …

Understanding Thermal Comfort Impact And Air Movement Around Open Stairs Through The Use Of Cfd Modeling, Ethan Davidson

Graduate Theses and Dissertations

The air exchange between two floors of a building has an impact on thermal comfort. The present research attempts to quantify this impact and identify the contributing factors disrupting the thermal comfort on and around stairs. Various heating and cooling scenarios were analyzed, using CFD modeling, in a simple two-story building separated by a single staircase. The research examines a single building layout with a fixed inlet and outlet configuration. In addition, the study investigated the short-term impact on thermal comfort. As a result, the duration of the simulations varies from two and half minutes to ten minutes, consistent with …

Development Of An Accelerated Life Testing Method For Reliability Assessment Of Wire Bonded Interconnects Subjected To Mechanical And Electromigratory Stresses, Whit Vinson

Graduate Theses and Dissertations

Power electronic advancement trends indicate that device power density will continue to increase as a result of increased power requirements and desired device form factor reduction in order to reduce weight and material costs and increase ease of integration into next-generation power systems. With these advancements come concerns regarding device reliability. The compounded effects of increased power density and form factor reduction in electrical conductors will yield amplified joule heating effects in addition to the already increasing device temperature profiles resulting from the incorporation of wide bandgap technology into power systems. Joule heating effects can lead to a variety of …

Dc Microgrid Fault Detection Using Multiresolution Analysis Of Traveling Waves, Rudy Montoya

Mechanical Engineering ETDs

Fast detection and isolation of faults in a DC microgrid is of particular importance. Fast tripping protection (i) increases the lifetime of power electronics (PE) switches by avoiding high fault current magnitudes and (ii) enhances the controllability of PE converters. This thesis proposes a traveling wave (TW) based scheme for fast tripping protection of DC microgrids. The proposed scheme utilizes a discrete wavelet transform (DWT) to calculate the high-frequency components of DC fault currents. Multiresolution analysis (MRA) using DWT is utilized to detect TW components for different frequency ranges. The Parseval energy calculated from the MRA coefficients are then used …

Zero-Power Ac Current Sensor, Omar Aragonez

Mechanical Engineering ETDs

In this study, a magnetic piezoelectric cantilever powered AC current and frequency sensor is proposed. This paper covers the configuration of the experimental setup, finite element modeling of the magnetic coupling, and the optimal spatial location of the magnetic proof mass in relation to the wire for smart grid applications. Solid and stranded copper wires of various gauges were used and carried current up to 30A. The magnets act as a proof mass to lower the frequency while also coupling to the magnetic field generated by the current carrying wire. The frequency of the AC current produces a sinusoidal force …