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Full-Text Articles in Mechanical Engineering

Design And Simulation Analysis Of A Bipv (Building Integrated With Pv) Air-Duct System For Residential High-Performance Development, Arash Zarmehr Jan 2023

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-

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 …


Lithium-Ion Battery Prognosis With Variational Hybrid Physics-Informed Neural Networks, Renato Giorgiani Do Nascimento Jan 2022

Lithium-Ion Battery Prognosis With Variational Hybrid Physics-Informed Neural Networks, Renato Giorgiani Do Nascimento

Electronic Theses and Dissertations, 2020-

Lithium-ion batteries are an increasingly popular source of power for many electric applications. Applications range from electric cars, driven by thousands of people every day, to existing and future air vehicles, such as unmanned aircraft vehicles (UAVs) and urban air mobility (UAM) drones. Therefore, robust modeling approaches are essential to ensure high reliability levels by monitoring battery state-of-charge (SOC) and forecasting the remaining useful life (RUL). Building principled-based models is challenging due to the complex electrochemistry that governs battery operation, which would entail computationally expensive models not suited for prognosis and health management applications. Alternatively, reduced-order models can be used …


Synthesis And Assessment Of Sustainable Fuels For Transportation And Space Exploration, Katerina Chagoya Dec 2021

Synthesis And Assessment Of Sustainable Fuels For Transportation And Space Exploration, Katerina Chagoya

Electronic Theses and Dissertations, 2020-

As global energy sources transition towards renewable energy, the demand for sustainable fuels has never been greater. The sheer scale of this transition will require numerous solutions to accommodate for the diverse and complex situations worldwide. This dissertation will discuss 3 studies: the utilization of CO2 waste gas to produce fuels sustainably, characterizing biofuels for efficient use in automobiles, and developing a solid, emissonless fuel intended for spaceflight but also applicable on Earth. The hydrogenation of CO2 into value-added molecules could reduce greenhouse gas emissions if waste stream CO2 were captured for conversion. We found that atomic vacancies induced in …


Connected Water Heater Load Shifting And Energy Efficiency Evaluation For The Southeast: Winter Laboratory Assessment, Final Report, Florida Solar Energy Center, Karen Fenaughty Jun 2021

Connected Water Heater Load Shifting And Energy Efficiency Evaluation For The Southeast: Winter Laboratory Assessment, Final Report, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

The University of Central Florida's FSEC Energy Research Center (FSEC) and Pacific Northwest National Laboratory (PNNL) are conducting laboratory electrical load shifting experiments using the CTA-2045-A standard to demonstrate the viability of grid-connected heat pump water heaters (HPWH), compared to electric resistance water heaters (ERWH), in providing load shifting in the Southeastern United States (U.S.). The investigation applied different CTA-2045 shed and critical peak (CP) control command designs under two different water draw profiles. The highly-controlled laboratory experiments were conducted on four HPWHs and one ERWH from December 2020 through February 2021.

The research aimed to evaluate the load shifting …


Comparison Of The Residential Provisions Of The 7th Edition (2020) Florida Building Code, Energy Conservation With The 2021 Iecc, Florida Solar Energy Center, Jeffrey Sonne Jun 2021

Comparison Of The Residential Provisions Of The 7th Edition (2020) Florida Building Code, Energy Conservation With The 2021 Iecc, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

This report provides a comparison between the 7th Edition (2020) Florida Building Code, Energy Conservation (FBC-EC) and 2021 International Energy Conservation Code (IECC), based on approved 2018 to 2021 IECC changes included in the International Code Council's Complete Revision History to the 2021 I-Codes document. The first part of this study involved developing code change listings based on the Revision History document that identify changes that have potential energy and cost impacts. This second part of the study provides a stringency evaluation and cost-benefit analysis for those changes that impact energy use, to provide guidance for the upcoming 2020 FBC-EC …


Comparison Of The Commercial Provisions Of The 2020 Florida Building Code, Energy Conservation, 7th Edition With 2021 Iecc & Ashrae 90.1-2019, Florida Solar Energy Center, Bereket Nigusse Jun 2021

Comparison Of The Commercial Provisions Of The 2020 Florida Building Code, Energy Conservation, 7th Edition With 2021 Iecc & Ashrae 90.1-2019, Florida Solar Energy Center, Bereket Nigusse

FSEC Energy Research Center®

This report provides comparison of the commercial provisions of the 7th Edition (2020) Florida Building Code, Energy Conservation (FBC-EC) with the 2021 International Energy Conservation Code (IECC) and ASHREA 90.1-2019. The first part developed code changes listing identifying energy and construction cost impacts. The second part analyzed energy and energy cost savings potential of the 2021 IECC and the 2019 ASHRAE 90.1 compared to the 2020 FBC-EC using prototype buildings energy model and simulation. And performed cost-benefit analysis of code changes with energy impact and provided recommendation for consideration by Florida Building Commission for addition to the 8th Edition (2023) …


Mitigation Of Airborne Contaminant Spread Through Simple Interventions In An Occupied Single-Family Home, Florida Solar Energy Center, Nazim Muradov May 2021

Mitigation Of Airborne Contaminant Spread Through Simple Interventions In An Occupied Single-Family Home, Florida Solar Energy Center, Nazim Muradov

FSEC Energy Research Center®

Historically, reducing aerosol-based transmission of respired viruses in indoor environments has been of importance for controlling influenza viruses and common-cold rhinoviruses. The present public health emergency associated with SARS-CoV-2 makes this topic critically important. Yet to be tested is the potential effectiveness of simple interventions that create an isolation zone (IZ) for a suspected/confirmed sick or sensitive person requiring quarantine. The intent in existing homes is to find a practical means to mitigate exposure to airborne contaminants. In creating an IZ in an occupied single-family home in the study, four simple strategies were tested. The test configurations were: (1) IZ …


Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes, Florida Solar Energy Center, Tanvir Khan May 2021

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

Existing evidence strongly suggests that viral infectious diseases can be transmitted via an airborne route across distances in indoor environments. Accordingly, the risk of airborne transmission within homes should be managed. The public health emergency associated with SARS-CoV-2 makes controlling airborne transmission of respired viruses in indoor environments critical, especially in poorly ventilated indoor environments. The effectiveness of engineering interventions requiring minor efforts that create a negative-pressure isolation zone (IZ) for a contagious person has yet to be tested for existing residential homes.

To mitigate the risk of airborne virus transmission and maximize health protection for the population in existing …


Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes -- Fact Sheet, Florida Solar Energy Center, Tanvir Khan May 2021

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes -- Fact Sheet, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

The FSEC Energy Research Center at the University of Central Florida performed research to test the effectiveness of interventions to isolate an ill person recovering from a contagious disease in a single-family home from the rest of the occupants in the home. Focus was placed on interventions requiring minor cost and effort on the part of the occupants.

DOE/GO-102021-5537, https://www.nrel.gov/docs/fy21osti/79519.pdf


Survey Of Unvented Attics In Climate Zone 2a, Florida Solar Energy Center, Eric Martin Mar 2021

Survey Of Unvented Attics In Climate Zone 2a, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

Moisture risk must be managed in unvented attics to ensure durability of components and longevity of the system. The FSEC Energy Research Center (FSEC), at the University of Central Florida tested and collected data in six homes in the northern Florida portion of IECC Climate Zone 2A built after 2015 with unvented (semi-conditioned) attics to add to the body of knowledge on the accumulation of moisture in the attic and its effects on roof moisture that can impact durability.


Relative International Energy Conservation Code (Iecc) Energy Impacts By Compliance Path, Florida Solar Energy Center, Philip Fairey Mar 2021

Relative International Energy Conservation Code (Iecc) Energy Impacts By Compliance Path, Florida Solar Energy Center, Philip Fairey

FSEC Energy Research Center®

The EnergyGauge® USA (v.6.2) residential building energy simulation software tool is used to examine energy impacts in two-story, 2,376 ft2, single-family homes configured in accordance with the minimum requirements of Section R402-R404 of the 2018 IECC in fourteen representative U.S. cities.4 EnergyGauge USA is a RESNET-accredited HERS software tool capable of evaluating not only the HERS Index and the IECC Section R406 Energy Rating Index Compliance Alternative but also the IECC Section R405 Simulated Performance Alternative as well as the IECC Section R402 R-Value and Total UA Alternative prescriptive methods along with all of the IECC mandatory …


Resilient Florida Buildings: Alternative Fuel Options For Maintaining Power During Outages, Brochure, Florida Solar Energy Center, Colleen Kettles Feb 2021

Resilient Florida Buildings: Alternative Fuel Options For Maintaining Power During Outages, Brochure, Florida Solar Energy Center, Colleen Kettles

FSEC Energy Research Center®

Electricity outages impact buildings as well as the fueling infrastructure that delivers energy resources for power generation and transportation. A fueling infrastructure with minimal downtime during power outages is needed to increase the resiliency of buildings and the economy. This brochure describes alternative fuels to consider for a buildings resiliency plan. This material is based upon work supported by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE) under the Energy Technology Development Program Award Number DE-EE0008880. FSEC Art#: BLDG-89 Updated: 05/20/2021


Metal And Flexible Duct Systems Impacts Upon Cooling Energy And Performance, Florida Solar Energy Center, Charles Withers, Jr. Jan 2021

Metal And Flexible Duct Systems Impacts Upon Cooling Energy And Performance, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Flexible duct is commonly used throughout the U.S. in residential construction. It performs well when installed in accordance with industry standards, however, they are often not installed as such. Issues such as not cutting ducts to the exact length needed, and instead using significantly more duct, result in compression and higher static pressure. Poorly supported ducts or turns without proper radius also increase static pressure. A research project was completed to evaluate the differences in performance between a metal duct and flexible duct systems in two side-by-side otherwise identical residential laboratories. Testing evaluated three different flex duct system configurations compared …


Studies On Powder Compaction And Wire Extrusion Of Pure Metals And Metal/Cnt Nano Composites, Qiang Zhou Jan 2021

Studies On Powder Compaction And Wire Extrusion Of Pure Metals And Metal/Cnt Nano Composites, Qiang Zhou

Electronic Theses and Dissertations, 2020-

The goal of this dissertation is to fabricate wires made of Cu/CNT and Al/CNT composites with good mechanical strength and super thermal/electrical conductivities using powder compaction and wire extrusion manufacturing processes. Powder compaction was studied using both test and simulation. Cold compaction, hot compaction and vibration assisted (cold) compaction tests were conducted to achieve different density ratios. Hot compaction tests improved about 6% compared with cold compaction under the same compression pressure. Although the relative density ratio does not obviously improve at vibration assisted (cold) compaction, the strength of the specimens made under vibration loading is much better than those …


Econometric Frameworks For Energy Prediction, Naveen Chandra Iraganaboina Jan 2021

Econometric Frameworks For Energy Prediction, Naveen Chandra Iraganaboina

Electronic Theses and Dissertations, 2020-

Global warming and associated role of energy consumption across various sectors is a well-researched topic in recent years. Understanding current urban energy consumption patterns will allow us to understand how future energy consumption patterns will evolve. With electrification of vehicles and potentially altering culture of work from home, the energy usage at regional level would see a significant change in the future. The current PhD dissertation contributes to energy consumption analysis of a region by analyzing residential energy consumption, commercial energy consumption and transportation energy use by households. The aggregation of these energy consumption within a region contributes to the …


Harvesting Heat From Safer, Energy-Dense Slow Pyrolant Mixtures For Future Space Missions, Katerina Chagoya Jan 2021

Harvesting Heat From Safer, Energy-Dense Slow Pyrolant Mixtures For Future Space Missions, Katerina Chagoya

Electronic Theses and Dissertations, 2020-

Energy sources powering space missions range from highly energetic nuclear reactions to short-lifetime and low-output batteries. The proper selection of a power system is dependent on the mission duration and destination and oftentimes energy sources that may be optimal for the former may be unsuitable for the latter. Various limitations of these power sources hinder the capacity for regular and frequent space exploration. However, the ability to harvest heat for electrical power generation would allow for long-distance and long-duration missions at a reduced cost. By employing a regulated, self-propagating, exothermic chemical reaction between solid fuel and oxidizer, we hope to …


Florida Building Code, Energy Conservation, 7th Edition (2020) Vs. 2018 International Energy Conservation Code Residential Stringency Analysis, Florida Solar Energy Center, Jeffrey Sonne Dec 2020

Florida Building Code, Energy Conservation, 7th Edition (2020) Vs. 2018 International Energy Conservation Code Residential Stringency Analysis, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

This report summarizes the review and evaluation activities carried out to make a determination whether the residential provisions of the 7th Edition (2020) Florida Building Code, Energy Conservation meet or exceed those of the 2018 International Energy Conservation Code (IECC) code.


Market Driven Residential Energy Codes: Comparing Performance In A Changing Technical Environment, Code Official Survey Results, Florida Solar Energy Center, Karen Fenaughty Dec 2020

Market Driven Residential Energy Codes: Comparing Performance In A Changing Technical Environment, Code Official Survey Results, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

The DOE Code Survey conducted for this project was launched on 2/18/2020 and closed 3/20/2020. There were 907 participants responding to at least some portion of the 48 question survey, though some questions received poor attention. Note that the number of responses to each question varies by design and depends on answers to prior questions. Further, multiple answers are sometimes allowed.


Fsec Energy Research Center Highlights 2020, Brochure, Florida Solar Energy Center, Sherri Shields Sep 2020

Fsec Energy Research Center Highlights 2020, Brochure, Florida Solar Energy Center, Sherri Shields

FSEC Energy Research Center®

This 5-page "brochure" provides an overview of capabilities at the FSEC Energy Research Center. As Florida's statewide energy research center, FSEC has a 45-year history of basic and applied research excellence, which has grown in scope to include all aspects of renewable energy, energy storage, electric vehicles, and energy efficiency technologies. FSEC's education and outreach programs have trained thousands of energy practitioners and informed energy consumers. This document was originally created to inform City of Cocoa Council members about FSEC during their external visit to the Center in June 2020, during COVID-19. FSEC Art#: PIO-104


Who's Leading: The Dance Between Mini-Splits And Existing Hvac Systems, Florida Solar Energy Center, Cheryn Metzger Aug 2020

Who's Leading: The Dance Between Mini-Splits And Existing Hvac Systems, Florida Solar Energy Center, Cheryn Metzger

FSEC Energy Research Center®

Recently, many utilities across the U.S. have provided incentives for ductless mini-split heat pumps due to their relatively high efficiencies. However, when these ductless mini-splits are installed in existing homes, utilities and researchers find that they are not living up to their energy saving potential, due to a lack of coordinated controls with the existing HVAC system. The Pacific Northwest National Laboratory (PNNL), the Florida Solar Energy Center (FSEC), and The Levy Partnership are all leading projects across the country to address this problem. The goal for this body of work is to determine which control strategies provide the most …


Characterization Of Mechanical Ventilation Systems In New Us Homes: What Types Of Systems Are Out There And Are They Functioning As Intended?, Florida Solar Energy Center, Eric Martin Aug 2020

Characterization Of Mechanical Ventilation Systems In New Us Homes: What Types Of Systems Are Out There And Are They Functioning As Intended?, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

As the airtightness of homes improves to meet energy efficiency goals, it becomes more important for mechanical ventilation systems to help maintain a comfortable and healthy indoor air environment. ASHRAE Standard 62.2 provides national guidance for mechanical ventilation system design and installation, however adoption of those guidelines into local building codes has occurred at different rates. Once provisions for mechanical ventilation are adopted in a local code, are mechanical ventilation systems properly designed, installed, commissioned and operated according to code or above-code program requirements? This paper presents results from field studies that include characterization of whole house mechanical ventilation (WHMV) …


Targeting The Best Performing Home Efficiency Programs With Advanced Metering Evaluation Supplemented By Simulation, Florida Solar Energy Center, Robin Vieira Aug 2020

Targeting The Best Performing Home Efficiency Programs With Advanced Metering Evaluation Supplemented By Simulation, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

The authors investigated the impacts of seven residential rebate energy efficiency programs offered by a municipal utility. The evaluation examined energy use pre and post retrofit using the Advanced Mete1ing Infrastructure (AMI) data, disaggregated by major end-use and weather-adjusted; and also by detailed simulations. Residences modeled were representative of typical participants for that measure based on factors such as year built, conditioned square feet and number of bedrooms.

Our analysis found the residential rebate programs to be of highly varied effectiveness, but important differences surfaced between the simulation and the AMI data evaluation. Not surprisingly, programs with larger samples tended …


Measured Cooling Energy Savings From Reflective Wall Finishes: Evaluation As An Efficiency Measure Across Climates, Florida Solar Energy Center, Danny Parker Aug 2020

Measured Cooling Energy Savings From Reflective Wall Finishes: Evaluation As An Efficiency Measure Across Climates, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

In past research, reflective roofs have shown significant potential to reduce cooling in buildings. However, there have been few empirical evaluations of cooling reductions from changing wall reflectance. In the reported study, several experiments with instrumented scale test buildings are used to provide validation for a detailed simulation analysis across varied North American climates. The simulations establish the potential of reflective walls as an efficiency measure in existing buildings against climate.

This paper was published in the 2020 ACEEE Summer Study on Energy Efficiency in Buildings.


Analysis Techniques For Evaluating Energy Conservation Programs Using Utility Ami Data, Florida Solar Energy Center, Richard Raustad Aug 2020

Analysis Techniques For Evaluating Energy Conservation Programs Using Utility Ami Data, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

With the evolution of Advanced Metering Infrastructure (AMI) electric meters, utility companies now have direct access to whole building electricity use at a granular time scale. AMI data can be used for a variety of purposes beyond billing, for example, to evaluate the efficacy of energy conservation (EC) programs. Historical methods for calculating EC program savings include building simulation models and laboratory and/or field testing. With big data now available, which analysis methods are more likely to yield quality results?

In a recent project, the Orlando Utility Commission provided monitored AMI data from Oct 1, 2015 - Sep 27, 2018 …


Improving Energy Savings And Peak Demand Reduction Estimates Using Ami Data For Utility Commercial Rebate Programs, Florida Solar Energy Center, Karen Fenaughty Aug 2020

Improving Energy Savings And Peak Demand Reduction Estimates Using Ami Data For Utility Commercial Rebate Programs, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

Solar reflective, or cool roofs, are a demonstrated method of reducing air conditioning energy, particularly in cooling-dominated climates. Similarly, efficient lighting or mechanical equipment replacement programs have a reputation for achieving large savings in c01mnercial buildings. Savings estimates for such measures have historically used monthly utility bills, which only provide a macroscopic view of utility program savings. Advanced Metering Infrastructure (AMI) is commonly used in the U.S. by utilities for residential and commercial customers and provides not only a valuable record of changing premise energy use and demand profiles but in much greater detail than utility bills, if desired.

Partnering …


Measured Energy And Moisture Performance Impacts From Vented And Unvented Attic With Insulation On Top Of Ceiling In The Hot Humid Climate Zone, Florida Solar Energy Center, Charles Withers, Jr. Aug 2020

Measured Energy And Moisture Performance Impacts From Vented And Unvented Attic With Insulation On Top Of Ceiling In The Hot Humid Climate Zone, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Sealing attic vents helps decrease house air leakage and may reduce some moisture issues in attics in hot humid climates. new code-approved unvented attics can use different types of insulation materials, however, there are specific requirements that vary by materials used and climate zone. These requirements may be complex and may increase construction and operational energy costs.

This paper was published in the 2020 ACEEE Summer Study on Energy Efficiency in Buildings.


Fsec Energy Research Center Strategic Plan (2020-2025) Executive Summary, Florida Solar Energy Center, James Fenton Jun 2020

Fsec Energy Research Center Strategic Plan (2020-2025) Executive Summary, Florida Solar Energy Center, James Fenton

FSEC Energy Research Center®

The Florida Legislature created the Florida Solar Energy Center (FSEC) in 1975 to support the growth and development of renewable energy. The year 2025 will mark the half-century mark for FSEC's service as the statewide energy research and education institute. In preparation for the next 50 years of dynamic energy developments, the FSEC Energy Research Center is undertaking a strategic planning and rebranding process.


Side-By-Side Testing Of Solaire Solar Ac, Florida Solar Energy Center, John Sherwin Jan 2020

Side-By-Side Testing Of Solaire Solar Ac, Florida Solar Energy Center, John Sherwin

FSEC Energy Research Center®

The FSEC Energy Research Center performed a series of side-by-side tests to compare a heat pump system with a SolAire thermal collector against one without. The tests were performed in three phases: 1) baseline operation, 2) heat pump system operating with SolAire collector using collector manufacturer's wiring specifications, and 3) heat pump system operating with SolAire collector using Daiken/OEM wiring specifications. Each phase represented 5 full days of continuous operation during August of 2018 in Cocoa, Florida. Phase 1 baseline testing demonstrated that the two Daiken heat pump systems and test houses performed similarly and there were no differences between …


Engineering The Surface Chemistry And Surface Conditions To Optimize The Heat Removal Rate Of Various Surfaces, Thomas Germain Jan 2020

Engineering The Surface Chemistry And Surface Conditions To Optimize The Heat Removal Rate Of Various Surfaces, Thomas Germain

Electronic Theses and Dissertations, 2020-

As the demand for more powerful and smaller electronics rise, the need for creative cooling solutions to prevent burnout becomes increasingly paramount. In response to recent cooling needs, new cooling techniques, such as jet impingement cooling, spray cooling, and heat pipes, have risen in popularity for their simple design and efficiency in thermal transport. This interest has risen in both industry and academia, where research has been conducted to optimize the heat transfer performance for these systems and how these systems can be implemented in new technologies. One method that has risen in interest is affecting the surface, through physical …


Design Of An Annular Disc-Shaped Heat Pipe For Air-Cooled Steam Condensers, Ahmad Saleh Jan 2020

Design Of An Annular Disc-Shaped Heat Pipe For Air-Cooled Steam Condensers, Ahmad Saleh

Electronic Theses and Dissertations, 2020-

Limitations on water utilization are turning into an expanding issue for the power and electricity generation industry. As a contribution to the solution of water consumption problems, utility companies are shifting toward using air-cooled condensers (ACC) in replace to the typical water-cooling methods of once-through cooling and the surface condenser/wet-cooling tower combination. Although the ACC is a dry cooling method, the industry is quite hesitant to switch over to ACC mainly for three reasons: (a) lower power output, (b) higher capital cost, and (c) larger physical footprint. All these drawbacks are because of the high overall thermal resistance of condensing …