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Full-Text Articles in Engineering

Mathematical Modeling Of Fruit Drying And System Analysis Of The Process (On The Example Of Persimmon), Gani Dadayev, Jasur Safarov, Shakhnoza Sultanova, Qobiljon Muxiddinov Jan 2024

Mathematical Modeling Of Fruit Drying And System Analysis Of The Process (On The Example Of Persimmon), Gani Dadayev, Jasur Safarov, Shakhnoza Sultanova, Qobiljon Muxiddinov

Technical science and innovation

Vegetable raw materials, as an object of drying, are characterized by a large amount of water and a low content of dry substances. Vegetable raw materials have a capillary-porous structure. Food products contain both bound and free moisture at the same time. The removal of moisture from the material during drying depends on the total moisture content and the form of connection of moisture with the material. Adsorption and osmotic - bound moisture is retained at the interface of colloidal particles with the environment. Food products contain both bound and free moisture at the same time. The quantitative ratio between …


Evaluation Of Digital Twin Approaches For Thermal Modeling And Energy Optimization For Existing Buildings, Jason Bastie Muermann Sep 2023

Evaluation Of Digital Twin Approaches For Thermal Modeling And Energy Optimization For Existing Buildings, Jason Bastie Muermann

Theses and Dissertations

Residential, commercial, and industrial building sectors in the United States were responsible for 42% of the nation’s consumption of 100.2 quadrillion BTUs of energy in 2019 [1]. 80% of the nation’s energy is sourced from fossil fuels, including coal, natural gas, and petroleum. Fossil fuels are known contributors to carbon emissions and climate change, making energy reduction vital. Consequently, New Jersey Department of Military and Veterans Affairs (NJDMAVA) is tasked with evaluating energy consumption and efficiency in all New Jersey Army National Guard (NJARNG) facilities, as mandated by TAG Policy Letter 18-5, Executive Order 13990, and the Energy Independence and …


Heat Transfer Characteristics Of Latent Heat Thermal Energy Storage, Kedar Prashant Shete Apr 2023

Heat Transfer Characteristics Of Latent Heat Thermal Energy Storage, Kedar Prashant Shete

Doctoral Dissertations

Latent heat thermal energy storage (LHTES) systems can be used to reduce electric demand when used in conjunction with Combined Heat and Power Plants or HVAC(Heating, Ventilation, Refrigeration and Air-Conditioning), as they can regulate the demand and supply of thermal energy. They can also be used to integrate renewable energy sources with the grid. A design procedure and performance modeling is required for designing and using thermal energy storage systems effectively. We propose hypotheses about the performance of an LHTES device with different operating conditions and material properties, for devices that are governed by different modes of heat transfer. We …


Halloysite Reinforced Natural Esters For Energy Applications, Jaime Taha-Tijerina, Karla Aviña, Victoria Padilla-Gainza, Aditya Akundi Feb 2023

Halloysite Reinforced Natural Esters For Energy Applications, Jaime Taha-Tijerina, Karla Aviña, Victoria Padilla-Gainza, Aditya Akundi

Informatics and Engineering Systems Faculty Publications and Presentations

Recently, environmentally friendly and sustainable materials are being developed, searching for biocompatible and efficient materials which could be incorporated into diverse industries and fields. Natural esters are investigated and have emerged as eco-friendly high-performance alternatives to mineral fluids. This research shows the evaluations on thermal transport and tribological properties of halloysite nanotubular structures (HNS) reinforcing natural ester lubricant at various filler fractions (0.01, 0.05, and 0.10 wt.%). Nanolubricant tribotestings were evaluated under two configurations, block-on-ring, and 4-balls, to obtain the coefficient of friction (COF) and wear scar diameter (WSD), respectively. Results indicated improvements, even at merely 0.01 wt.% HNS concentration, …


System Analysis Of An Internal Combustion Engine (Ice) – Solid Oxide Fuel Cell (Sofc) Hybrid Cycle, Jose Javier Colon Rodriguez Jan 2023

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 …


Elevation-Distributed Multistage Reverse Osmosis Desalination With Seawater Pumped Storage, Hani E. Elsayed-Ali Jan 2023

Elevation-Distributed Multistage Reverse Osmosis Desalination With Seawater Pumped Storage, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

A seawater reverse osmosis (RO) plant layout based on multistage RO with stages located at different elevations above sea level is described. The plant uses the weight of a seawater column from pumped storage as head pressure for RO (gravity-driven multistage RO) or to supplement high-pressure pumps used in RO (gravity-assisted multistage RO). The use of gravitational force reduces the specific energy for RO compared to using high-pressure pumps. By locating the RO stages at different elevations based on demand sites, the total specific energy consumption for RO and permeate transport to different elevations above sea level is reduced from …


Development And Testing Of A 1:70 Scale Model Wind Turbine Of The Iea Reference 15 Mw Floating Offshore System, Amber Parker May 2022

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 …


Energy Planning Model Design For Forecasting The Final Energy Consumption Using Artificial Neural Networks, Haidy Eissa Dec 2021

Energy Planning Model Design For Forecasting The Final Energy Consumption Using Artificial Neural Networks, Haidy Eissa

Theses and Dissertations

“Energy Trilemma” has recently received an increasing concern among policy makers. The trilemma conceptual framework is based on three main dimensions: environmental sustainability, energy equity, and energy security. Energy security reflects a nation’s capability to meet current and future energy demand. Rational energy planning is thus a fundamental aspect to articulate energy policies. The energy system is huge and complex, accordingly in order to guarantee the availability of energy supply, it is necessary to implement strategies on the consumption side. Energy modeling is a tool that helps policy makers and researchers understand the fluctuations in the energy system. Over the …


Modeling Portfolios Of Low Carbon Energy Generation Under Deep Uncertainty, Franklyn Kanyako Oct 2021

Modeling Portfolios Of Low Carbon Energy Generation Under Deep Uncertainty, Franklyn Kanyako

Doctoral Dissertations

In the 2015 Paris Agreement, nearly every country pledge through the Nationally Determined Contributions (NDCs) increased adoption of low carbon energy technologies in their energy system. However, allocating investments to different low carbon energy technologies under rising demand for energy and budget constraints, uncertain technical change in these technologies involves maneuvering significant uncertainties among experts, models, and decision-makers. We examine the interactions of low carbon energy sources (LCES) under the condition of deep uncertainty. Deep uncertainty directly impacts the understanding of the role of low carbon energy technologies in climate change mitigation and how much R&D investment should be allocated …


Dynamic Hvac Energy Management Using Commercial Building Occupancy Metrics & Neural Networks, Krishna Chaitanya Jagadeesh Simma Jul 2021

Dynamic Hvac Energy Management Using Commercial Building Occupancy Metrics & Neural Networks, Krishna Chaitanya Jagadeesh Simma

Civil Engineering ETDs

With the rise of technology use in buildings, it is now possible to collect data that can be used to improve building energy consumption. One factor that has significant impact on building energy consumption is occupancy. Recent studies have shown promising results in obtaining occupancy information from existing infrastructure such as WiFi router networks. However, these existing frameworks require additional investments through software upgrades, added infrastructure, computational resources, and may raise occupant privacy concerns. Additionally, with occupant thermal comfort statistics being lower than ASHAREA specified standards, a novel approach for indoor climate control is needed. To address the limitations in …


Cal Poly Wind Power: Wind Turbine Prototype, Sophie A. Spencer, Maggie Nevrly, Michael Reyna, Loi Q. Nguyen Jun 2021

Cal Poly Wind Power: Wind Turbine Prototype, Sophie A. Spencer, Maggie Nevrly, Michael Reyna, Loi Q. Nguyen

Mechanical Engineering

The Cal Poly Wind Power (CPWP) club is competing in the Collegiate Wind Competition (CWC) hosted by the National Renewable Energy Laboratory (NREL). The CWC is hosted annually by NREL to increase the number of skilled workers prepared to work in the wind energy industry. Our senior project team is one of several design teams contributing to the CPWP prototype turbine design including the pitching mechanism, blade design, generator, and shaft. The scope of this project is to design the yaw mechanism, tower, and nacelle. The goal is to create components that function well with other planned components and are …


Sustainable Energy Storage, Jacob S. Grillo, Alyse C. Coonce, Jack R. Linchey, Nick P. Schnorr Jun 2021

Sustainable Energy Storage, Jacob S. Grillo, Alyse C. Coonce, Jack R. Linchey, Nick P. Schnorr

Mechanical Engineering

This Final Design Review document covers the work we, students at California Polytechnic State University – San Luis Obispo, have performed in collaboration with Mr. Harish Bhutani and Dr. Mohammad Noori. The project’s intent is to create an energy storage system for off-grid and developing region applications using alternative technologies to lithium-ion battery storage. We plan to manufacture and assemble a scale model of the energy storage system to prove effectiveness and practicality. This system will store enough energy to power basic appliances and essential devices for a house or community. The chosen design direction will be a flywheel, as …


Feasibility Study Of Portable Solar Powered Blood Storing Refrigerator, Saroj Subedi May 2021

Feasibility Study Of Portable Solar Powered Blood Storing Refrigerator, Saroj Subedi

Honors Theses

This report is focused on the preliminary feasibility of portable solar-powered blood-storing refrigerators primarily based on calculations of energy required to maintain the temperature of the refrigerator, the electricity required throughout the day, calculating sufficiency of power supplied by the solar panel, and selection of battery for power storage. The method and the trend of a feasibility study involve the study of blood properties, separation of blood components after donation, and their storage conditions. Then, the portable size of the refrigeration has been proposed with three different compartments for storage of each blood component. The further methods involve the selection …


Smud Solar Regatta, Logan Garby, Nam Le, Jacob Singer, Alejandro Carrera, Laura Casas Mar 2021

Smud Solar Regatta, Logan Garby, Nam Le, Jacob Singer, Alejandro Carrera, Laura Casas

Mechanical Engineering

The Sacramento Municipal Utility District (SMUD) hosts the Solar Regatta every year in Rancho Seco, CA, a competition which consists of teams building a solar powered boat to compete in three races: the sprint race, endurance race, and slalom race. The Cal Poly Solar Regatta team was informed mid-project by SMUD that the competition has been canceled once again for spring 2021, but the team decided to move forward with the construction of the boat. The previous Cal Poly team from 2019/2020 designed the hull and propulsion system of the boat. The 2020/2021 team worked with the previous team in …


A Theoretical Study On Integration And Optimization Of Gas Turbine Problems With Solar Energy System, Ahmad M. Abubaker Jan 2021

A Theoretical Study On Integration And Optimization Of Gas Turbine Problems With Solar Energy System, Ahmad M. Abubaker

Theses and Dissertations--Mechanical Engineering

Gas Turbine (GT) power plants suffer from sensitivity to ambient-air temperatures, high fuel consumption, and a high amount of waste heat dumped into the ambient. Various solutions were proposed to solve these drawbacks, which could simultaneously solve at most two problems, usually at the expense of the third. For instance, inlet-air cooling can reduce ambient-air temperatures but will result in increased fuel consumption. However, in this work, a novel cascaded system was integrated into a combined cycle, capable of simultaneously solving all the aforementioned GT drawbacks. Parabolic trough collectors were used to preheat the air at the combustion chamber inlet …


Use Of Energy Consumption During Milling To Fill A Measurement Gap In Hybrid Additive Manufacturing, K. L. M. Avegnon, P. Noll, M. R. Uddin, G. Madireddy, R. Williams, A. Achuthan, M. P. Sealy Jan 2021

Use Of Energy Consumption During Milling To Fill A Measurement Gap In Hybrid Additive Manufacturing, K. L. M. Avegnon, P. Noll, M. R. Uddin, G. Madireddy, R. Williams, A. Achuthan, M. P. Sealy

Department of Mechanical and Materials Engineering: Faculty Publications

Coupling additive manufacturing (AM) with interlayer peening introduces bulk anisotropic properties within a build across several centimeters. Current methods to map high resolution anisotropy and heterogeneity are either destructive or have a limited penetration depth using a nondestructive method. An alternative pseudo-nondestructive method to map high-resolution anisotropy and heterogeneity is through energy consumption during milling. Previous research has shown energy consumption during milling correlates with surface integrity. Since surface milling of additively manufactured parts is often required for post-processing to improve dimensional accuracy, an opportunity is available to use surface milling as an alternative method to measure mechanical properties and …


Triboelectric Energy Harvester With Large Bandwidth Under Harmonic And Random Excitations, Alwathiqbellah Ibrahim, Abdallah Ramini, Shahrzad Towfighian Nov 2020

Triboelectric Energy Harvester With Large Bandwidth Under Harmonic And Random Excitations, Alwathiqbellah Ibrahim, Abdallah Ramini, Shahrzad Towfighian

Mechanical Engineering Faculty Publications and Presentations

This paper investigates an approach to impact vibration energy harvesting using a triboelectric mechanism under harmonic and random excitation. The harvester consists of a clamped–clamped beam with a stiff plate in the middle to realize the impact electrification process when subjected to external vibrations. The harvester uses stiffening in the clamped–clamped beam introduced by the impact between two triboelectric layers to increase the frequency bandwidth. A piecewise theoretical model is used to model the harvester for two scenarios of motions, before and after impact. The harvester is tested experimentally under different harmonic excitation to validate the theoretical model. The outcomes …


Improving The Piezoelectric Properties Of Flexible Polymer-Nanoparticle Energy Harvesters, Muhammet Emin Cavusoglu Jun 2020

Improving The Piezoelectric Properties Of Flexible Polymer-Nanoparticle Energy Harvesters, Muhammet Emin Cavusoglu

Theses and Dissertations

In this research, one of the widely used polymers, poly(vinylidene fluoride)(PVDF), was used to develop thin-film polymer energy harvesters. Dimethylformamide (DMF) and methyl ethyl ketone (MEK) were used to dissolve the PVDF powder. Four different (0%, 3%, 5%, and 7%) ZnO nanoparticle (NP) concentrations were used to enhance the electrical output of the thin-film energy harvesters. A sonication bath and additional MEK were used in dispersing the ZnO NPs to obtained uniform PVDF/ZnO NP solution. The electrode poling technique was used for dipole alignment to improve the electrical performance of the devices. The fabricated samples were tested using the tensile …


Integrated Resource Plan For Portland General Electric (Pge), Mary Biswal, Alejandro Castelan May 2020

Integrated Resource Plan For Portland General Electric (Pge), Mary Biswal, Alejandro Castelan

Master's Projects and Capstones

An integrated resource plan (IRP) for Portland General Electric (PGE) is developed in this master’s project. The IRP is based on capacity expansion modeling for zero-carbon emission scenarios. PGE is a public electric utility based in Oregon and serves around 887,000 customers across a territory of 4,000 sq. miles. The utility’s resource mix is currently heavily dependent on natural gas making up almost 50% of its capacity. While the state renewable portfolio standards (RPS) require Oregon power utilities to derive 50% of their generation from renewable sources by 2040, PGE plans to move rapidly into a clean energy mix by …


An Integrated Resource Plan For Arizona Public Service Electric (Aps), Irene Boghdadi, Randy Chiu May 2020

An Integrated Resource Plan For Arizona Public Service Electric (Aps), Irene Boghdadi, Randy Chiu

Master's Projects and Capstones

Our Masters Capstone Project is an Integrated Resource Plan (IRP) for Arizona’s largest electric utility, Arizona Public Service Electric (APS).

An IRP is developed by utilities to identify the optimal combination of demand- and supply-side resources needed to reliably meet forecasted demand for energy and capacity, including a planning reserve margin, over a future period.

In addition to APS’s obligation to serve the growing load in Arizona while minimizing costs, it is required by the state to adhere to the Renewable Energy Standard (RES) policy of 15 percent retail sales from renewable energy resources by 2025.

The analysis described in …


An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald May 2020

An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald

Honors Scholar Theses

The purpose of this project is to design a clean energy-sourced microgrid for UConn’s main campus that would reduce the university’s energy emissions while remaining within the geographic boundaries of viable UConn-owned land. Economic cost was not considered in this analysis; instead, emissions and space constraints were the optimized measures of value and feasibility. Sources of energy that were considered include photovoltaics (PV), wind turbines, hydrokinetic systems, and fuel cells. Energy storage capacity was included in the analysis as well. The overall system was optimized first by ignoring space constraints and for a minimum of 10% reduction from the current …


Adaptable Clean Energy Laboratory, Joao Marcelo Rocha Belmonte, Marc D. Compere Jan 2020

Adaptable Clean Energy Laboratory, Joao Marcelo Rocha Belmonte, Marc D. Compere

Sustainability Conference

The Adaptable Clean Energy (ACE) Lab is a real-world, long term, test platform that will guide the courses of the Energy Systems track. The lab will provide realistic electrical and HVAC loads that mimic a solar powered office. The lab is a 20’ high cube shipping container modified with a door, windows, lights computers, air conditioner and appliances. The lab is Net-Zero and powered entirely from the sun. Two insulation test sections expose the exterior walls for research access to real external heat loads in a real building


Dual-Axis Solar Tracker, Bryan Kennedy Jan 2020

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …


On The Energy Sustainability Of Active And Passive Building Integrated Technologies In The Context Of A Changing Climate For Tropical Coastal Cities, Rabindra Pokhrel Jan 2020

On The Energy Sustainability Of Active And Passive Building Integrated Technologies In The Context Of A Changing Climate For Tropical Coastal Cities, Rabindra Pokhrel

Dissertations and Theses

Caribbean Sea surface temperatures have been rising at an alarming rate of 0.020C/year. The effect of rising sea surface temperatures is reflected in increasing in 2m air temperature over the Caribbean. The rise in extreme temperatures increases human discomfort and energy demands for air conditioning (AC) putting both the population and energy infrastructure at higher risk of vulnerability. This vulnerability is amplified in compact cities where anthropogenic heat removal from the built environment further increases the temperature of the urban canyon with feedback on human comfort and energy demands. Although there has been prior work reported on mitigating energy demands …


Hvac System Energy Audit For Leverett Elementary School, Connor Smalling Dec 2019

Hvac System Energy Audit For Leverett Elementary School, Connor Smalling

Biological and Agricultural Engineering Undergraduate Honors Theses

Leverett Elementary School is located in Fayetteville, AR. The school needs significant upgrades to its infrastructure. The Fayetteville Public School District has voted to pursue an Energy Services Performance Contract (ESPC) in order to finance the desired upgrades to Leverett Elementary, among other schools in the district.

The scope of this thesis was to perform an energy audit on the existing heating, ventilation, and air conditioning (HVAC) system. By using an energy modeling software, eQuest, the building and the existing base system were modeled to determine utility consumption. Three different HVAC system alternatives were analyzed against the base system by …


Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James Aug 2019

Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Expanders allow pressurized fluids to undergo a pressure decrease in a controlled environment via volumetric growth to extract fluid energy. There are many types of expanders, and the objective of this thesis is to model the efficiencies of the planetary rotor expander (PRE), a century-old design undeveloped due to insufficient manufacturing capabilities (until recently). Geometric relationships are derived and mathematical models are generated to determine the efficiency of the PRE as a function of design variables. Two industrially relevant case studies show that, to maximize isentropic efficiency, the planetary rotor expander (PRE) rotational frequency is maximized and rotor geometry optimized.


Swarm Behavior To Mitigate Rebound In Air Conditioning Demand Response Events, Jason Yasuto Kuwada Aug 2019

Swarm Behavior To Mitigate Rebound In Air Conditioning Demand Response Events, Jason Yasuto Kuwada

Boise State University Theses and Dissertations

Thermostatically Controlled Loads (TCLs) have shown great potential for Demand Response (DR) events. However, it has been commonly seen that DR events using TCLs may cause demand rebound, especially in homogeneous populations. To further explore the potential for DR events, as well as the negative effects, a stability and resilience analysis were performed on multiple populations and verified with agent based modeling simulations.

At the core of this study is an added thermostat criterion created from the combination of a proportional gain and the average compressor operating state of neighboring TCLs. Where DR events in TCLs are commonly controlled by …


Energy Transformation And Conservation Investigation, Mike Jackson, Holly Haney Jul 2019

Energy Transformation And Conservation Investigation, Mike Jackson, Holly Haney

High School Lesson Plans

Students will use a thermoelectric generator module to analyze the relationship between thermal and electrical energies. Using data collection sensors and analysis software, students will investigate the relationship between the temperature gradient across a thermoelectric generator module and the resulting electrical potential. Students will then use their data and analysis to solve problems relating to waste thermal energy in electrical systems and communicate their work to their peers and teacher.


Numerical Investigation Of Coalescence-Induced Self-Propelled Behavior Of Droplets On Non-Wetting Surfaces And Wedged Surfaces., Yan Chen May 2019

Numerical Investigation Of Coalescence-Induced Self-Propelled Behavior Of Droplets On Non-Wetting Surfaces And Wedged Surfaces., Yan Chen

Electronic Theses and Dissertations

When small drops coalesce on a superhydrophobic surface, the merged drop can jump away from the surface due to the surface energy released during the coalescence. This self-propelled behavior has been observed on various superhydrophobic surfaces and has potential applications in areas related to the heat and mass transfer, such as heat exchangers, anti-icing and anti-frost devices, thermal management and water harvesting. The jumping velocity model was obtained based on published experimental data and the balance of various energy terms described in previous studies. However, the self-propelled mechanism is still not fully understood. In this study, the self-propelled droplet phenomenon …


Solar Tracker Renewable Energy, Stephanie Christie, Annabeth Helmly, Matthew Smith, Katrina Vaughan Jan 2019

Solar Tracker Renewable Energy, Stephanie Christie, Annabeth Helmly, Matthew Smith, Katrina Vaughan

ENERGY Research and Lesson Plans

No abstract provided.