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Full-Text Articles in Mechanical Engineering

Energy Savings And Peak Demand Reduction Of A Seer 21 Heat Pump Vs. A Seer 13 Heat Pump With Attic And Indoor Duct Systems - December 2011, Florida Solar Energy Center, James Cummings Dec 2011

Energy Savings And Peak Demand Reduction Of A Seer 21 Heat Pump Vs. A Seer 13 Heat Pump With Attic And Indoor Duct Systems - December 2011, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Experiments were run in an unoccupied 1600 ft2 house, the Manufactured Housing (MH Lab) at the Florida Solar Energy Center (FSEC), to evaluate the delivered performance as well as the relative performance of a SEER 21 variable capacity heat pump versus a SEER 13 heat pump. The performance was evaluated with two different duct systems: a standard attic duct system and an indoor duct system located in a dropped-ceiling space.


Investigation On Interactions Of Unsteady Wakes And Film Cooling On An Annular Endwall, Matthew J. Golsen Dec 2011

Investigation On Interactions Of Unsteady Wakes And Film Cooling On An Annular Endwall, Matthew J. Golsen

HIM 1990-2015

In recent decades, greater interest in the effect of rotational wakes on gas turbine film cooling applications has produced increasing numbers of studies on these unsteady phenomena. Wakes are primarily shed from upstream components such as transition duct walls, stator vanes, and rotors. Studies have shown that in areas of unsteady flow, the best performing parameters in conventional steady investigations may not be the best for unsteady applications. One common method of modeling the unsteady wake interaction in subsonic flows is the use of spoke wheel type wake generators using cylindrical rods to produce the velocity detriment and local increase …


Florida Solar Atlas, Florida Solar Energy Center, Charles Cromer Jul 2011

Florida Solar Atlas, Florida Solar Energy Center, Charles Cromer

FSEC Energy Research Center®

The direct beam and direct global solar resource values for any geographical location in Florida were found by using actual data taken at the Florida Solar Energy Center (FSEC) for 2010 and correlating those values against clearness values derived from NOAA geostationary satellite data. Using the correlations developed, eleven years of satellite data (2000 - 2010) were used to provide expected monthly average solar resource values for any location in Florida. These values as provided in watts per meter square per day, were matched to colors with the lowest values of the full range of average values representing the deepest …


New Construction Builders Challenge: Sealed Attic And High Efficiency Hvac In Central Florida: A Year In Review Monitored Prototypes - Springwater Homes, Florida Solar Energy Center, Carlos Colon May 2011

New Construction Builders Challenge: Sealed Attic And High Efficiency Hvac In Central Florida: A Year In Review Monitored Prototypes - Springwater Homes, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

In 2010 the Florida Solar Energy Center (FSEC), with funding from the Building America program, was involved with a new Builders Challenge builder located in Rockledge, Florida -- Springwater Homes (see figure 1). The newly constructed home in March 2010, features a sealed attic with R-27 roof deck insulation (shown in figure 2). Selection of the HVAC system, an important aspect to achieve high efficiency levels in buildings, ended with one of the highest residential equipment systems available in the U.S., the Nutone IQ Drive (SEER 21). The house was confirmed with a HERS index of 53 using the EnergyGauge …


An Experimental And Numerical Study Of Secondary Flows And Film Cooling Effectiveness In A Transonic Cascade, James C. Kullberg May 2011

An Experimental And Numerical Study Of Secondary Flows And Film Cooling Effectiveness In A Transonic Cascade, James C. Kullberg

HIM 1990-2015

Experimental tests on a transonic annular rig are time-consuming and expensive, so it is desirable to use experimental results to validate a computational model which can then be used to extract much more information. The purpose of this work is to create a numerical model that can be used to simulate many different scenarios and then to apply these results to experimental data.; In the modern world, gas turbines are widely used in aircraft propulsion and electricity generation. These applications represent a massive use of energy worldwide, so even a very small increase in efficiency would have a significant beneficial …


Arra Advanced Weatherization Training Center - Quarterly Report (January 2011-March 2011), Florida Solar Energy Center, Neil Moyer Apr 2011

Arra Advanced Weatherization Training Center - Quarterly Report (January 2011-March 2011), Florida Solar Energy Center, Neil Moyer

FSEC Energy Research Center®

The 1st quarter of 2011 was the beginning of procurement for the training center. Two pieces of equipment, the insulation blowing machine and infrared cameras, were put out for quotes. Both have been selected and purchase orders created.


Building America Industrialized Housing Partnership (Baihp Ii)Final Report Budget Periods 1-5, April 1, 2006 - November 30, 2010, Florida Solar Energy Center, Robert Abernethy Mar 2011

Building America Industrialized Housing Partnership (Baihp Ii)Final Report Budget Periods 1-5, April 1, 2006 - November 30, 2010, Florida Solar Energy Center, Robert Abernethy

FSEC Energy Research Center®

This report summarizes the work conducted by the Building America Industrialized Housing Partnership (BAIHP - www.baihp.org) during the final budget period (BP5) of our contract, January 1, 2010 to November 30, 2010. Highlights from the four previous budget periods are included for context.

BAIHP is led by the Florida Solar Energy Center (FSEC) of the University of Central Florida. With over 50 Industry Partners including factory and site builders, work in BP5 was performed in six tasks areas:

  • Task 1: Building America System Research Management, Documentation and Technical Support
  • Task 2A: Stage G1A: Integrated Solutions for Specific Climate Regions
  • Task …


Short-Term Curtailment Of Hvac Loads - Executive Summary, Florida Solar Energy Center, Lixing Gu Jan 2011

Short-Term Curtailment Of Hvac Loads - Executive Summary, Florida Solar Energy Center, Lixing Gu

FSEC Energy Research Center®

Rapidly increasing requirements placed on utilities to reduce peak loads has led to utility customer incentives to shift peak demand to non-peak times or reduce peak loads when notified by the utility that the grid is close to capacity. This study investigates methods used to reduce building demand during a fixed time window near a utilities on-peak period. The window was chosen to be 5-9 A.M. in winter and 2-5 P.M. in summer.The most common methods for reducing building peak demand were reviewed and categorized by their usefulness and wide-spread availability. These strategies were reductions in lighting power density, global …


Arra Advanced Weatherization Training Center - Quarterly Report (September 2010-December 2010), Florida Solar Energy Center, Neil Moyer Jan 2011

Arra Advanced Weatherization Training Center - Quarterly Report (September 2010-December 2010), Florida Solar Energy Center, Neil Moyer

FSEC Energy Research Center®

The 4th quarter of 2010 was the initialization of the contract with DOE. During this time period, there were two major events that occurred. First, representatives from UCF-FSEC attended the three day Atlanta Weatherization Training Center Grantee Training Workshop with DOE representatives and the various organizations that were awarded funding. Secondly, the project management plan (PMP) was finalized and submitted to the Project Manager.


Heat Transfer And Friction Augmentation In A Narrow Rectangular Duct With Symmetrical And Non-Symmetrical Wedge-Shaped Turbulators, Michelle Valentino Jan 2011

Heat Transfer And Friction Augmentation In A Narrow Rectangular Duct With Symmetrical And Non-Symmetrical Wedge-Shaped Turbulators, Michelle Valentino

Electronic Theses and Dissertations

The need for cleaner and more fuel efficient means to produce electricity is growing steadily. Advancements in cooling technologies contribute to the improvements in turbine efficiency and are used for gas turbines and for power generation in automotive, aviation, as well as in naval applications, and many more. Studies introducing turbulators on walls of internal cooling channels, which can be applied to hot gas components and in recuperative heat exchangers, have been reviewed for their ability to promote heat transfer in the channel while observing pressure loss caused by adding the features. Several types of turbulators have been studied; ribs, …


Measurements In Air-Water Bubbly Flow Through A Vertical Narrow High-Aspect Ratio Channel, Benjamin R. Patrick Jan 2011

Measurements In Air-Water Bubbly Flow Through A Vertical Narrow High-Aspect Ratio Channel, Benjamin R. Patrick

Electronic Theses and Dissertations

Two-Phase bubbly flows are encountered in a wide range of industrial applications, particularly where phase changes occur as seen in high performance heat exchangers and boiling reactors for power generation. These flows have been extensively studied in channels with circular geometries using air-water flows, though little data exists for flows through narrow rectangular channels. Measurements in thin geometries are particularly challenging since large bubbles bridge the gap, and it is difficult to compare point measurements with photographic techniques. The objective of this study is to explore the abilities of hot-film anemometry and high speed photography for taking measurements in a …


Effect Of Rib Aspect Ratio On Heat Transfer And Friction In Rectangular Channels, Lucky Vo Tran Jan 2011

Effect Of Rib Aspect Ratio On Heat Transfer And Friction In Rectangular Channels, Lucky Vo Tran

HIM 1990-2015

The heat transfer and friction augmentation in the fully developed portion of a 2:1 aspect ratio rectangular channel with orthogonal ribs at channel Reynolds numbers of 20,000, 30,000, and 40,000 is studied both experimentally and computationally. Ribs are applied to the two opposite wide walls. The rib aspect ratio is varied systematically at 1, 3, and 5, with a constant rib height and constant rib pitch (rib-pitch-to-rib-height ratio of 10). The purpose of the study is to extend the knowledge of the performance of rectangular channels with ribs to include high aspect ratio ribs. The experimental investigation is performed using …


Toward Increasing Performance And Efficiency In Gas Turbines For Power Generation And Aero-Propulsion Unsteady Simulation Of Angled Discrete-Injection Coolant In A Hot Gas Path Crossflow, Perry L. Johnson Jan 2011

Toward Increasing Performance And Efficiency In Gas Turbines For Power Generation And Aero-Propulsion Unsteady Simulation Of Angled Discrete-Injection Coolant In A Hot Gas Path Crossflow, Perry L. Johnson

HIM 1990-2015

This thesis describes the numerical predictions of turbine film cooling interactions using Large Eddy Simulations. In most engineering industrial applications, the Reynolds-Averaged Navier-Stokes equations, usually paired with two-equation models such as k-Greek lowercase letter epsilon] or k-Greek lowercase letter omega], are utilized as an inexpensive method for modeling complex turbulent flows. By resolving the larger, more influential scale of turbulent eddies, the Large Eddy Simulation has been shown to yield a significant increase in accuracy over traditional two-equation RANS models for many engineering flows. In addition, Large Eddy Simulations provide insight into the unsteady characteristics and coherent vortex structures of …


Heat Transfer Study Of A Triple Row Impingement Channel At Large Impingement Heights, Roberto Claretti Jan 2011

Heat Transfer Study Of A Triple Row Impingement Channel At Large Impingement Heights, Roberto Claretti

HIM 1990-2015

Advanced cooling techniques are required to increase the Brayton cycle temperature ratio necessary for the increase of the overall cycle's efficiency. Current turbine components are cooled with an array of internal cooling channels in the midchord section of the blade, pin fin arrays at the trailing edge and impingement channels in the leading edge. Impingement channels provide the designer with high convective coefficients on the target surface. Increasing the heat transfer coefficient of these channels has been a subject of research for the past 20 years. In the current study, a triple row impingement channel is studied with a jet …


Study Of High Efficiency Micro Thermoelectric Energy Harvesters, Steven Michael Pedrosa Jan 2011

Study Of High Efficiency Micro Thermoelectric Energy Harvesters, Steven Michael Pedrosa

Electronic Theses and Dissertations

Thermal energy sources, including waste heat and thermal radiation from the sun, are important renewable energy resources. Thermal energy can be converted into electricity by thermoelectric phenomena; the thermoelectric phenomena can also be operated in reverse when provided an electric current, producing a temperature gradient across the device. Thermoelectric devices are scalable, renewable, and cost effective products that offer capabilities to harness waste heat or environmental heat sources, and convert the captured heat into usable electricity. The operating principle of a thermoelectric device requires that a temperature gradient be present across the device, which induces the flow of electrons from …


Modeling Of Thermal Properties Of Fiber Glass Polyester Resin Composite Under Thermal Degradation Condition, Marvin S. Tsoi Jan 2011

Modeling Of Thermal Properties Of Fiber Glass Polyester Resin Composite Under Thermal Degradation Condition, Marvin S. Tsoi

Electronic Theses and Dissertations

Composites, though used in a variety of applications from chairs and office supplies to structures of U.S. Navy ships and aircrafts, are not all designed to hold up to extreme heat flux and high temperature. Fiber-reinforced polymeric composites (FRPC) have been proven to provide the much needed physical and mechanical properties under fire exposure. FRPC notable features are its combination of high specific tensile strength, low weight, along with good corrosion and fatigue resistance. However FRPC are susceptible to thermal degradation and decomposition, which yields flammable gas, and are thus highly combustible. This property restricts polymeric material usage. This study …


Purge And Secondary Flow Interaction Control By Means Of Platform Circumferential Contouring, Melissa Harris Jan 2011

Purge And Secondary Flow Interaction Control By Means Of Platform Circumferential Contouring, Melissa Harris

Electronic Theses and Dissertations

This study presents an attempt to reduce the losses produced by the purge flow in a turbine stage by incorporating circumferential platform contouring. Two contours are proposed and compared against a baseline at different levels of swirl. The computational simulations were performed using a RANS three-dimensional Computational Fluid Dynamics code with the Shear Stress Transport turbulence model. The results of steady simulations demonstrate that for the first contour, when the flow is swirled to 50% of the rim speed, the purge flow exits the cavity with less cross flow. This in turn reduces the strength of the passage vortex. However, …


Design And Optimization Of A Wave Energy Harvester Utilizing A Flywheel Energy Storage System, Steven Alexander Helkin Jan 2011

Design And Optimization Of A Wave Energy Harvester Utilizing A Flywheel Energy Storage System, Steven Alexander Helkin

Electronic Theses and Dissertations

This thesis details the design and optimization of a buoy used to collect renewable energy from ocean waves. The proposed buoy is a point absorber—a device that transforms the kinetic energy of the vertical motion of surface waves into electrical energy. The focus of the research is on the mechanical system used to collect the energy, and methods to improve it for eventual use in an actual wave energy harvester. A flywheel energy storage system was utilized in order to provide an improved power output from the system, even with the intermittent input of force exerted by ocean waves. A …


Heat Transfer In A Coupled Impingement-Effusion Cooling System, Mark W. Miller Jan 2011

Heat Transfer In A Coupled Impingement-Effusion Cooling System, Mark W. Miller

Electronic Theses and Dissertations

Gas turbine engines are prevalent in the today’s aviation and power generation industries. The majority of commercial aircraft use a turbofan gas turbine engines. Gas turbines used for power generation can achieve thermodynamic efficiencies as high as 60% when coupled with a steam turbine as part of a combined cycle. The success of gas turbines is a direct result of a half century’s development of the technology necessary to create such efficient, powerful, and reliable machines. One key area of technical advancement is the turbine cooling system. In short, increasing the turbine inlet temperature leads to a rise in cycle …


Multi-Sensor Optimization Of The Simultaneous Turning And Boring Operation, Erick Johan Deane Jan 2011

Multi-Sensor Optimization Of The Simultaneous Turning And Boring Operation, Erick Johan Deane

Electronic Theses and Dissertations

To remain competitive in today’s demanding economy, there is an increasing demand for improved productivity and scrap reduction in manufacturing. Traditional manufacturing metal removal processes such as turning and boring are still one of the most used techniques for fabricating metal products. Although the essential metal removal process is the same, new advances in technology have led to improvements in the monitoring of the process allowing for reduction of power consumption, tool wear, and total cost of production. Replacing used CNC lathes from the 1980’s in a manufacturing facility may prove costly, thus finding a method to modernize the lathes …