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Full-Text Articles in Engineering

Thermodynamic Analysis Of Closed Steady Or Cyclic Systems, Jim A. Mcgovern Sep 2015

Thermodynamic Analysis Of Closed Steady Or Cyclic Systems, Jim A. Mcgovern

Articles

Closed, steady or cyclic thermodynamic systems, which have temperature variations over their boundaries, can represent an extremely large range of plants, devices or natural objects, such as combined heating, cooling and power plants, computers and data centres, and planets. Energy transfer rates can occur across the boundary, which are characterized as heat or work. We focus on the finite time thermodynamics aspects, on energy-based performance parameters, on rational efficiency and on the environmental reference temperature. To do this, we examine the net work rate of a closed, steady or cyclic system bounded by thermal resistances linked to isothermal reservoirs in …


An Energy Cube Project For Teaching Engineering Design Process, Fionnuala Farrell, Shannon Chance, Micheal O'Flaherty Sep 2015

An Energy Cube Project For Teaching Engineering Design Process, Fionnuala Farrell, Shannon Chance, Micheal O'Flaherty

Conference papers

This year, the College of Engineering and the Built Environment at our institute inaugurated a new Common First Year design project module that helps inform students in the selection of a specific engineering discipline. Each student, prior to selecting their bachelor’s specialism, completes three group-based design projects: a bridge design project (to familiarise students with civil and structural engineering), a RoboSumo project (involving robotics, programming, electrical and electronics engineering), and an Energy Cube project (introducing fundamentals of mechanical, manufacturing and design, and building services engineering). This paper focuses on how the engineering design process was taught via the Energy Cube. …


Assessment Of Critical Technologies For Gas Turbine Engines Using Numerical Tools, Vinicius Pessoa Mapelli, Guillermo Paniagua, Jorge Sousa Aug 2015

Assessment Of Critical Technologies For Gas Turbine Engines Using Numerical Tools, Vinicius Pessoa Mapelli, Guillermo Paniagua, Jorge Sousa

The Summer Undergraduate Research Fellowship (SURF) Symposium

In 2014 gas turbine engine has reached a market value of 82.5 billion dollars, of which 59.5% are related to aircraft propulsion. The continuous market expansion attracts more and more the interest of researchers and industries towards the development of accurate numerical techniques to model thermodynamically the entire engine. This practice allows a performance and optimization analysis before the actual experimental testing, reducing the time and required investment in the design of a new engine. In this paper, a recently developed open source numerical tool named “Toolbox for the Modeling and Analysis of Thermodynamic Systems” (T-MATS) is used to assess …


Hot Surface Ignition, Yerbatyr Tursyn, Vikrant Goyal, Alicia Benhidjeb-Carayon, Richard Simmons, Scott Meyer, Jay P. Gore Aug 2015

Hot Surface Ignition, Yerbatyr Tursyn, Vikrant Goyal, Alicia Benhidjeb-Carayon, Richard Simmons, Scott Meyer, Jay P. Gore

The Summer Undergraduate Research Fellowship (SURF) Symposium

Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas turbine fuels Jet-A, JP-8, and JP-5 were measured. A test apparatus capable of providing reproducible data was designed and fabricated to experimentally investigate the hot surface ignition …


Fracture Mechanics-Based Simulation Of Pv Module Delamination, Dominic I. Jarecki, Johanna B. Palsdottir, Peter Bermel, Marisol Koslowski Aug 2015

Fracture Mechanics-Based Simulation Of Pv Module Delamination, Dominic I. Jarecki, Johanna B. Palsdottir, Peter Bermel, Marisol Koslowski

The Summer Undergraduate Research Fellowship (SURF) Symposium

Photovoltaic (PV) cells are rapidly growing as a renewable alternative to fossil fuels like coal, oil, and natural gas. However, greater adoption has also reduced government subsidies, placing the onus of making solar panels economically competitive on innovative research. While multiple methods have been considered for reducing costs, with each reduction in cost comes the associated peril of reduction in quality and useful lifetime. Several problems considered solved have now resurfaced as potential failure mechanisms with the introduction of cheaper PV cell technologies. However, to remain economically viable, PV modules will not only have to become cheaper, they will have …


Three-Dimensional Scaffolds Of Graphene, Carbon Nanotubes And Transition-Metal Oxides For Applications In Electronics, Sensors And Energy Storage, Gilbert N. Mbah Aug 2015

Three-Dimensional Scaffolds Of Graphene, Carbon Nanotubes And Transition-Metal Oxides For Applications In Electronics, Sensors And Energy Storage, Gilbert N. Mbah

Department of Chemistry: Dissertations, Theses, and Student Research

Electronics, sensors and energy storage devices are the new waves behind economic development, security and communication1. Engineering small sizes of electronic, sensors and energy storage devices is the hurdle limiting efficient, portable and vast applications of Nano-devices for economic, security and communication advancement2. Silicon the major material used in transistors has approached its limit to fabricated Nano-devices3. The discovery of free standing, one atomic layer thick and two-dimensional graphene sheets with high conductivity, inert, high specific surface area, stable and high tensile strength material in 2004 has shown capabilities to replaced silicon in electronics, …


Triboelectric Solar Generator Concept And Experimental Research, Elias Yazdanshenas Jul 2015

Triboelectric Solar Generator Concept And Experimental Research, Elias Yazdanshenas

Mechanical & Aerospace Engineering Theses & Dissertations

In this thesis, a novel concept, a triboelectric solar generator (TSG ), is proposed for generation of high voltage direct current (HVDC) electricity from solar radiation. An experimental investigation was conducted to prove the concepts of charge generation through the triboelectric effect and charge transmission using semiconductors. The triboelectric effect, also known as the contact electrification, is a well-known physical phenomenon that electrostatic charges are generated by rubbing dissimilar materials. However, traditional triboelectric generators had never been commercialized due to their poor power output. Physically, it is due to the difficulty of charge transmission from insulators, which generate charges. The …


Sunsense/Sunsmart Plus-Up Schools Program Final Inspection Report, Florida Solar Energy Center, Susan Schleith Jun 2015

Sunsense/Sunsmart Plus-Up Schools Program Final Inspection Report, Florida Solar Energy Center, Susan Schleith

FSEC Energy Research Center®

This report provides information regarding the photovoltaic systems that are associated with the 2014 Sunsense/Sunsmart School Plus-UP program. Dave Click led the project as Principal Investigator and technical expert. Susan Schleith, participated as Co-Principal Investigator and education/school liaison. Four schools participated in the program. Each of the photovoltaic systems installed at the schools was inspected by the University of Central Florida's Florida Solar Energy Center (FSEC), as well as the local authority having jurisdiction (AHJ). This report details the results of the final inspections associated with National Electric Code (NEC) and performance testing as required by the Sunsense/Sunsmart Schools Plus-UP …


The Epa P3 Program: An Opportunity For Growing Student Entrepreneurs, Marc Compere, Yan Tang, Yung Wong Jun 2015

The Epa P3 Program: An Opportunity For Growing Student Entrepreneurs, Marc Compere, Yan Tang, Yung Wong

Publications

In this paper we will share our experiences of fostering entrepreneurial spirit through projects funded by EPA (Environmental Protection Agency) P3 (People, Prosperity, and the Planet) Program which hosts the P3 collegiate competition for designing solutions for a sustainable future. Since 2012, we have integrated the P3 competition with the capstone design course of Clean Energy Systems track in mechanical engineering as an effective educational vehicle for introducing the concept of sustainable design. Since the competition focuses on designs which have values of real world application, it is also a great opportunity to create entrepreneurial spirit. We have successfully turned …


Investigation Of The Effectiveness And Failure Rates Of Whole-House Mechanical Ventilation Systems In Florida, Florida Solar Energy Center, Jeffrey Sonne Jun 2015

Investigation Of The Effectiveness And Failure Rates Of Whole-House Mechanical Ventilation Systems In Florida, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

This report presents the results of a field investigation of the effectiveness and failure rates of whole-house mechanical ventilation systems installed in Florida homes over the last 15 years. The report includes homeowner survey and ventilation system testing results and code modification recommendations based on study findings.


Cooling And Heating Season Impacts Of Right-Sizing Of Fixed- And Variable-Capacity Heat Pumps With Attic And Indoor Ductwork, Florida Solar Energy Center, James Cummings Jun 2015

Cooling And Heating Season Impacts Of Right-Sizing Of Fixed- And Variable-Capacity Heat Pumps With Attic And Indoor Ductwork, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

The U.S. Department of Energy's research team Building America Partnership for Advanced Residential Construction implemented two phases of experiments to examine the cooling and heating seasonal and peak demand performance of a variable-capacity 2-ton SEER 22 heat pump versus a 3-ton variable-capacity SEER 21 heat pump with attic ducts and indoor ducts. The experiments also compared the cooling and heating seasonal and peak demand performance of 2-ton versus 3-ton fixed-capacity SEER 13 heat pumps with attic ducts and indoor ducts.


Solar Decathlon 2015, Solar Cal Poly; Solar Cal Poly Project Engineers, Cristina Paquin, Julien Blarel, Sanchit Joshi Jun 2015

Solar Decathlon 2015, Solar Cal Poly; Solar Cal Poly Project Engineers, Cristina Paquin, Julien Blarel, Sanchit Joshi

Mechanical Engineering

No abstract provided.


Solar Cal Poly Active Hvac Project, James Cornish, Jake Cosmo, Patrick Weston Jun 2015

Solar Cal Poly Active Hvac Project, James Cornish, Jake Cosmo, Patrick Weston

Mechanical Engineering

For this project, the goal was to conceptualize, design, test, and implement an active HVAC system to be used in the Solar Cal Poly house competing in the Department of Energy’s 2015 Solar Decathlon. With many house iterations, it was decided to use a split system with an outdoor heat pump and indoor air handler, paired with a HRV for ventilation. Through system modeling using Design Builder and Energy Pro 6.5, the cooling load of the house was determined along with the cooling schedule. The foreseen safety precautions and limited construction time guided the entire project, along with the active …


Increasing Isentropic Efficiency With Hydrostatic Head And Venturi Ejection In A Rankine Power Cycle, Nathan Daniel Ruiz Jun 2015

Increasing Isentropic Efficiency With Hydrostatic Head And Venturi Ejection In A Rankine Power Cycle, Nathan Daniel Ruiz

Master's Theses

This thesis describes the modifications made to the Cal Poly Thermal Science Laboratory’s steam turbine experiment. While the use of superheating or reheating is commonly used to increase efficiency in a Rankine cycle the methods prove unfeasible in a small scale project. For this reason, a mathematical model and proof of concept design using hydrostatic head generated by elevation and venturi ejection for use by the condenser is developed along with the equations needed to predict the changes to the system. These equations were used to create software to predict efficiency as well as lay down the foundation for future …


Conversion Of A Gas Combustion Engine To An Electric Motor In A Porsche 924, Ashley Weed Jun 2015

Conversion Of A Gas Combustion Engine To An Electric Motor In A Porsche 924, Ashley Weed

BioResource and Agricultural Engineering

This paper is a walk-through of converting a gasoline Porsche 924 to and electric engine. The paper begins with steps on how to remove the gasoline engine. It then goes into setting up the electrical system for the new electric vehicle and then follows up with the motor installation. The end of the report discusses the testing and results of the electric vehicle and finishes up with recommendations to anyone who attempts a similar project.


Shark Alert: Early Warning System, Cory Peterson, Marc Rauschnot, Taylor Mcclain Jun 2015

Shark Alert: Early Warning System, Cory Peterson, Marc Rauschnot, Taylor Mcclain

Electrical Engineering

The Shark Alert Early Warning System is a device geared toward avid beach goers such as surfers, divers, and swimmers. The system is composed of an ultrasonic transmitter mounted on a shark’s dorsal fin and a receiver worn by the user around the ankle. The receiver alerts the user to the presence of a shark upon ultrasonic signal detection.

The receiver warns the user through both visual and tactile (vibration) alerts to ensure user notification. This circuit was built and tested in the EE labs and Recreation Center pools to determine transmission range. The receiver detects the transmitted signal up …


Power Maximization Of A Three-Phase Hydrokinetic Turbine, Matthew Carleson May 2015

Power Maximization Of A Three-Phase Hydrokinetic Turbine, Matthew Carleson

Senior Theses

As Earth`s expendable resources dwindle, the need for alternative, renewable energy sources grows. Out of this need, an old favorite source is rising in popularity: small water turbines. Water-driven turbines first began as a means for turning mills and eventually evolved into massive dams that can power whole regions. This project focused on the construction of, and testing the properties of, a small pico-hydro power turbine. By using compressed air to drive the turbine, a representation of the peak power output was measured, serving as a basis for determining the value of pico-power systems in regards to the world`s current …


Developing Exhaust Air Energy Recovery Credits For The Florida Energy Code, Florida Solar Energy Center, Bereket Nigusse May 2015

Developing Exhaust Air Energy Recovery Credits For The Florida Energy Code, Florida Solar Energy Center, Bereket Nigusse

FSEC Energy Research Center®

Energy Recovery Ventilator (ERV) or Heat Recovery Ventilator (HRV) devices recover energy from building's exhaust air to precondition outdoor air. Energy savings of ERV/HRV devices were determined for various commercial buildings in Florida climate using whole building energy simulation tool. The annual HVAC energy percent savings due to ERV/HRV device were calculated from HVAC energy use of a standard reference building without and with ERV/HRV device using EnergyPlus. The annual HVAC energy savings potential (ERV Credits) will be used for code compliance calculation when a compliance software does not have ERV modeling capability. The ERV/HRV credits were reported by building …


Maximum Energy Efficiency Cost Effectiveness In New Home Construction, Florida Solar Energy Center, Philip W. Fairey May 2015

Maximum Energy Efficiency Cost Effectiveness In New Home Construction, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

EnergyGauge® USA (v.4.0.00) is used to examine the cost effectiveness of high performance homes that are improved to significantly exceed the minimum requirements of the 2015 IECC. The objective of the study is to determine the maximum level of energy efficiency that can be considered cost effective to the consumer. For these purposes, it is the cost effectiveness of the entire package of measures that is considered by the analysis rather than the cost effectiveness of individual measures. Optimization and rank ordering of the individual improvement measures in the package is not considered by the analysis.

One-story 2,000 ft2 …


Maximum Power Point Tracking And Solar Power For Developing Countries Around The World, Christopher M. Plate May 2015

Maximum Power Point Tracking And Solar Power For Developing Countries Around The World, Christopher M. Plate

Electrical Engineering Undergraduate Honors Theses

Renewable energy is becoming increasingly important as more and more countries become industrialized. Using solar power as opposed to fossil fuels and coal is becoming cheaper and easier to access throughout the world, yet there are still efficiency hurdles to be overcome. Designing a cheap, easily modifiable and reparable Maximum Power Point Tracker would be a stepping stone to bringing solar power to remote parts of the globe. Once designed and made portable, these devices could be distributed throughout developing countries to enhance renewable energy output. An Arduino-based tracker was chosen for ease of use and access. This base also …


Improved Methods For Identifying, Applying, And Verifying Industrial Energy Efficiency Measures, Andrew Chase Harding May 2015

Improved Methods For Identifying, Applying, And Verifying Industrial Energy Efficiency Measures, Andrew Chase Harding

Graduate Theses and Dissertations

Energy efficiency is the least expensive source of additional energy capacity for today's global energy expansion. Energy efficiency offers additional benefits of cost savings for consumers, reduced environmental impacts, and enhanced energy security. The challenges of energy efficiency include identifying potential efficiency measures, quantifying savings, determining cost effectiveness, and verifying savings of installed measures. This thesis presents three separate chapters which address these challenges. The first is a paper presented at the 2014 industrial energy technology conference (IETC) that details a compressed air system project using the systems approach to identify cost effective measures, energy intensity to project savings, and …


Available Work Rate Of A Reversible System Bounded By Constant Thermal Resistances Linked To Isothermal Reservoirs, Jim Mcgovern May 2015

Available Work Rate Of A Reversible System Bounded By Constant Thermal Resistances Linked To Isothermal Reservoirs, Jim Mcgovern

Conference Papers

Exergy analysis is based on the concept of an idealized, all-enclosing reference environment that has infinite heat capacity and thermal conductivity, and is in equilibrium. The actual surroundings of a real plant such as a heat engine, a heat pump or a refrigerator may differ significantly from the ideal. First law performance parameters and second law rational efficiency are examined. The concepts of finite time thermodynamics are applied in an attempt to refine the concept of T0, the environmental reference temperature, thereby making exergy analysis more reflective of reality.


The Integration Of Heat Resources In A Solar Thermal-Heat Pump Hydronic System, John Degrove May 2015

The Integration Of Heat Resources In A Solar Thermal-Heat Pump Hydronic System, John Degrove

Purdue Polytechnic Masters Theses

According to the U.S. Department of Energy, roughly 41% of the energy consumed in the U.S. is used the power buildings. Within that number, almost half is used to heat or cool the building. Current technologies allow for consistent thermal management, but most utilize energy harvested from fossil fuels or convert electricity back into thermal energy. Background literature shows that the utilization of alternative heat resources such as heat pumps and solar thermal collectors can greatly reduce the energy used for heat delivery while producing adequate heating performance. A combined hydronic system using a bank of solar thermal collectors in …


Experimental Verification And Integration Of A Next Generation Smart Power Management System, Tavis Clemmer May 2015

Experimental Verification And Integration Of A Next Generation Smart Power Management System, Tavis Clemmer

Graduate Theses and Dissertations

With the increase in energy demand by the residential community in this country and the diminishing fossil fuel resources being used for electric energy production there is a need for a system to efficiently manage power within a residence. The Smart Green Power Node (SGPN) is a next generation energy management system that automates on-site energy production, storage, consumption, and grid usage to yield the most savings for both the utility and the consumer. Such a system automatically manages on-site distributed generation sources such as a PhotoVoltaic (PV) input and battery storage to curtail grid energy usage when the price …


Semi-Annual Program Progress Performance Report For The Electric Vehicle Transportation Center Pppr#3, Florida Solar Energy Center, David L. Block Apr 2015

Semi-Annual Program Progress Performance Report For The Electric Vehicle Transportation Center Pppr#3, Florida Solar Energy Center, David L. Block

FSEC Energy Research Center®

This document covers the program activities of the University of Central Florida's Electric Vehicle Transportation Center (EVTC) for the 6 month period of October 1, 2014 to March 31, 2015. The Electric Vehicle Transportation Center supports the U.S. Department of Transportation's strategic goal of planning for near-term integration of alternative fuel vehicles as a means to build a sustainable transportation system. The project objectives are to evaluate technologies, standards and policies to ensure seamless integration of electric vehicles (EVs) into a complex transportation network and electricity grid. The EVTC will bridge the gap between deployment of electric vehicles and the …


Electric Vehicle Sales For 2014 And Future Projections, Florida Solar Energy Center, David L. Block Apr 2015

Electric Vehicle Sales For 2014 And Future Projections, Florida Solar Energy Center, David L. Block

FSEC Energy Research Center®

The object of this research is to assess the current status and to predict the future penetration of electric vehicles (EVs) within the U.S. market. The prediction method is based on EV yearly sales giving the cumulative vehicles on the road for 2010 through 2014 and the growth rates for these five years. Using these growth values, the future ten year values are calculated. The EV sales results for 2014 in the U.S. show that 118,773 vehicles were sold as compared to 96,700 vehicles in 2013. This gives a one year sales growth rate of 23%. The total cumulative number …


Investigating Solutions To Wind Washing Issues In Two-Story Florida Homes, Phase 2, Florida Solar Energy Center, Charles Withers, Jr. Apr 2015

Investigating Solutions To Wind Washing Issues In Two-Story Florida Homes, Phase 2, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

With U.S. Department of Energy goals of reducing existing home energy use by 30% and new home energy use by 50%, it is imperative to focus on several energy efficiency measures, including the quality of air and thermal barriers. This report provides results from a second-phase research study of a phenomenon generally referred to as wind washing. Wind washing is the movement of unconditioned air around or through building thermal barriers in such a way as to diminish or nullify the intended thermal performance. This study focused on the impact of poorly sealed and insulated floor cavities adjacent to attic …


Characterization Of Wake Effects And Loading Status Of Wind Turbine Arrays Under Different Inflow Conditions, Xiangyu Gao Apr 2015

Characterization Of Wake Effects And Loading Status Of Wind Turbine Arrays Under Different Inflow Conditions, Xiangyu Gao

Open Access Theses

The objective of the present work is to improve the accuracy of Actuator Line Modeling (ALM) in predicting the unsteady aerodynamic loadings on turbine blades and turbine wake by assessing different methods used to determine the relative velocity between the rotating blades and wind. ALM is incorporated into a Large Eddy Simulation (LES) solver in OpenFOAM (Open Field Operations and Manipulations). The aerodynamic loadings are validated by experiment results from National Renewable Energy Laboratory (NREL). Turbine wakes are validated by predictions of large eddy simulation using exact 3D blade geometries from a two-blade NREL Phase VI turbine. Three different relative …


A Mechanical Regenerative Brake And Launch Assist Using An Open Differential And Elastic Energy Storage, David H. Myszka, Andrew P. Murray, Kevin Giaier, Vijay Krishna Jayaprakash, Christoph Gillum Apr 2015

A Mechanical Regenerative Brake And Launch Assist Using An Open Differential And Elastic Energy Storage, David H. Myszka, Andrew P. Murray, Kevin Giaier, Vijay Krishna Jayaprakash, Christoph Gillum

Mechanical and Aerospace Engineering Faculty Publications

Regenerative brake and launch assist (RBLA) systems are used to capture kinetic energy while a vehicle decelerates and subsequently use that stored energy to assist propulsion. Commercially available hybrid vehicles use generators, batteries and motors to electrically implement RBLA systems. Substantial increases in vehicle efficiency have been widely cited.

This paper presents the development of a mechanical RBLA that stores energy in an elastic medium. An open differential is coupled with a variable transmission to store and release energy to an axle that principally rotates in a single direction. The concept applies regenerative braking technology to conventional automobiles equipped with …


Vortex Identification In The Wake Of A Wind Turbine Array, Aleksandr Sergeyevich Aseyev Mar 2015

Vortex Identification In The Wake Of A Wind Turbine Array, Aleksandr Sergeyevich Aseyev

Dissertations and Theses

Vortex identification techniques are used to analyze the flow structure in a 4 x 3 array of scale model wind turbines. Q-criterion, Δ-criterion, and λ2-criterion are applied to Particle Image Velocimetry data gathered fore and aft of the last row centerline turbine. Q-criterion and λ2-criterion provide a clear indication of regions where vortical activity exists while the Δ-criterion does not. Galilean decomposition, Reynolds decomposition, vorticity, and swirling strength are used to further understand the location and behavior of the vortices. The techniques identify and display the high magnitude vortices in high shear zones resulting from the …