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Full-Text Articles in Mechanical Engineering

Field Measurement Of Uncontrolled Air Flow And Depressurization In Restaurants, Florida Solar Energy Center, James Cummings Dec 1996

Field Measurement Of Uncontrolled Air Flow And Depressurization In Restaurants, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Field investigations were done in seven restaurants (subsample of a 63 commercial buildings study) to identify uncontrolled air flows and pressure imbalances. Testing included building airtightness tests, identification of building air barrier location, duct system airtightness, characterization of pressure differentials, building air flow balance, and infiltration/ventilation rates. All restaurants were found to operate at negative pressures which ranged from -0.003 inWC (-0.8 Pa) to -0.173 inWC (-43 Pa) and averaged -0.051 inWC (-12.7 Pa) under normal operation. The variables which affect depressurization are large exhaust fans, missing or undersized make-up air, intermittent outdoor air caused by the cycling of air …


History Of Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young Sep 1996

History Of Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Hurricanes, floods, tornadoes, earthquakes, and other disasters can happen any place, any time. Major disasters destroy homes and businesses, and leave many people without adequate medical services, portable water, electrical service and communications. In response to the need for electrical service, solar energy offers a source of quite, safe, pollution-free power. Over the last few years, photovoltaic (solar electricity) power systems have provided energy for various disaster all over the country. Photovoltaics (PV) have been used to power vaccine refrigerators, medical equipment, lighting, radios, fans, communications, traffic devices and other electrical equipment. Previously, photovoltaics have supplied emergency power for Hurricane …


How Contractors Really Size Air Conditioning Systems, Florida Solar Energy Center, Robin Vieira Aug 1996

How Contractors Really Size Air Conditioning Systems, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

This paper presents results from 489 of the 5559 Florida air conditioning contractors surveyed (an 8.5% response rate) regarding equipment sizing methods in new residences. Air conditioning sizing is accomplished by using ACCA's Manual-J procedure by 33% of the respondents, software by 34.4% of the respondents, square-footage by 24.2% and other estimate procedures by about 8.4%. Those using square-footage estimates varied from 350 square-feet- per-ton to 700 square-feet-per-ton. Over a third of respondents indicated oversizing intentionally on some jobs, in order to avoid complaints, accommodate future expansions, enable quicker cooling down of homes, and to allow for lower cooling set …


Are Energy Savings Due To Ceiling Fans Just Hot Air?, Florida Solar Energy Center, Patrick James Aug 1996

Are Energy Savings Due To Ceiling Fans Just Hot Air?, Florida Solar Energy Center, Patrick James

FSEC Energy Research Center®

Human comfort studies have shown that people prefer higher temperatures when they are subjected to a breeze. Ceiling fans are often used to create air motion in residences. Simulation studies (including one given in this paper) have demonstrated that in Florida, using ceiling fans combined with raising a home's temperature 2° F will generate about a 14% net savings in annual cooling energy use (subtracting out the ceiling fan energy and accounting for internally released heat). This savings drops to 2.6% with a 1° F increase in set point and to a negative 3.7% savings with only a 0.5° F …


Daylight Dimming Systems: Studies In Energy Savings And Efficiency, Florida Solar Energy Center, Lynn Schrum Aug 1996

Daylight Dimming Systems: Studies In Energy Savings And Efficiency, Florida Solar Energy Center, Lynn Schrum

FSEC Energy Research Center®

Three studies were conducted at Florida Solar Energy Center (FSEC) to study the lighting energy savings of daylight dimming systems. The Daylighting Test Facility (DTF) was used to study daylight dimming systems and how aperture orientation and blinds affect performance. The energy consumption was compared in two pairs of offices for all four window orientations: north, south, east and west. One office in each pair had blinds in a fixed position (down and open) and the other office had no blinds. The study showed that the energy savings ranged from 24% to 51% depending on the orientation and blinds.

The …


Measured Field Performance And Energy Savings Of Occupancy Sensors: Three Case Studies, Florida Solar Energy Center, David Floyd Aug 1996

Measured Field Performance And Energy Savings Of Occupancy Sensors: Three Case Studies, Florida Solar Energy Center, David Floyd

FSEC Energy Research Center®

Occupancy sensors have the potential to significantly reduce energy use by switching off electrical loads when a normally occupied area is vacated. While occupancy sensors can be used to control a variety of load types, their most popular use has been to control lighting in commercial buildings. Manufacturers claim savings of 15% to 85%, although there is little published research to support the magnitude or timing of reductions. Energy savings and performance are directly related to the total wattage of the load being controlled, effectiveness of the previous control method, occupancy patterns within the space and proper sensor commissioning. In …


Demonstration Of Cooling Savings Of Light Colored Roof Surfacing In Florida Commercial Buildings: Our Savior's School, Florida Solar Energy Center, Danny Parker Jun 1996

Demonstration Of Cooling Savings Of Light Colored Roof Surfacing In Florida Commercial Buildings: Our Savior's School, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Architects and designers have long known that light-colored building roofs can reduce cooling needs. Recently, monitoring studies in Florida have made an effort to quantify these savings. Experiments in existing residences have shown that a white reflective roof can reduce cooling requirements by an average of 20%. However, until now there has been no investigation in Florida's climate to examine the potential in commercial scale buildings.

To remedy this need, a two year study was performed on a private elementary school building in Cocoa Beach, Florida. Our Savior's Elementary School was monitored for an entire year in a base line …


Flastar: Florida Alliance For Saving Taxes And Energy Resources. Final Report., Florida Solar Energy Center, John Sherwin Jun 1996

Flastar: Florida Alliance For Saving Taxes And Energy Resources. Final Report., Florida Solar Energy Center, John Sherwin

FSEC Energy Research Center®

This document comprises the final project report in supporting the demonstration of the pilot Florida Public Building Loan Concept. This loan program provides low cost funds to eligible public entities for upgrade of building energy systems. The FLASTAR program (Florida Alliance for Saving Taxes And Resources) was modeled after the successful Texas LoanSTAR project [1,2]. Within that program, funds provided from oil overcharges are loaned to various facilities for building system retrofits. These loans are repaid (with interest) from energy cost savings. As of the most recent reporting, the LoanSTAR program had saved the State of Texas some $13.7 million …


Results From A Comprehensive Residential Lighting Retrofit. 09-96, Florida Solar Energy Center, Danny Parker Jun 1996

Results From A Comprehensive Residential Lighting Retrofit. 09-96, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A single family residence in Miami, Florida was used as a case study to determine how residential lighting energy use could be reduced by substituting energy efficient lamps and fixtures. The three person household was chosen based both on its high utility bills and extensive use of interior lighting. A detailed audit revealed 40 lamps or bulbs on 26 controls (switches) with a total connected load of 2.5 kW.

All major energy using appliances in the home were sub-metered so that lighting and other plug loads could be differenced from the measured total power demand. Also, each of the individual …


Measured Impacts Of Air Conditioner Condenser Shading, Florida Solar Energy Center, Danny Parker May 1996

Measured Impacts Of Air Conditioner Condenser Shading, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A study has been conducted by the Florida Solar Energy Center (FSEC) to examine if space cooling energy savings can be achieved from shading of residential air conditioning (AC) condenser units. The investigation consisted of before-and-after experiments conducted on three homes over a two year period. A recent EPA study recommends shading of exterior AC condensers, using landscaping or other means, as a method to reduce space cooling energy use (Akbari et al., 1992).


Monitored Energy Use Patterns In Low-Income Housing In A Hot And Humid Climate, Florida Solar Energy Center, Danny Parker May 1996

Monitored Energy Use Patterns In Low-Income Housing In A Hot And Humid Climate, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) is metering energy use in two Habitat for Humanity developments. The objective is to understand how energy is used in low income housing and how it can be effectively reduced. The ten "control homes" come from a conventional housing project built by in 1993 Habitat for Humanity in Homestead, Florida. Another ten "experimental homes" have been recruited from the 190 home Jordan Commons development in the same vicinity. These houses, which are soon to be metered, are designed to be energy efficient with high SEER air conditioners, reflective roofing, solar water heaters and energy …


Side-By-Side Testing Of Commercial Office Lighting Systems: Two-Lamp Fluorescent Fixtures, Florida Solar Energy Center, Danny Parker May 1996

Side-By-Side Testing Of Commercial Office Lighting Systems: Two-Lamp Fluorescent Fixtures, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Lighting systems in commercial office buildings are primary determinants of building energy use. In warmer climates, lighting energy use has important implications for building cooling loads as well as those directly associated with illumination tasks. To research the comparative performance of conventional and advanced office lighting systems, Florida Solar Energy Center (FSEC) set up the Lighting Flexible Test Facility (LFTF) which allows side-by-side comparison of lighting options in two otherwise identical 2.7 m x 3.7 m (9' x 12') south facing offices.

The ceiling of the LFTF contains 0.61 m x 1.2 m (2' x 4') recessed fluorescent fixtures designed …


Measured Performance Of Energy-Efficient Computer Systems, Florida Solar Energy Center, David Floyd May 1996

Measured Performance Of Energy-Efficient Computer Systems, Florida Solar Energy Center, David Floyd

FSEC Energy Research Center®

The intent of this study is to explore the potential performance of both Energy Star computers/printers and add-on control devices individually, and their expected savings if collectively applied in a typical office building in a hot and humid climate. Recent surveys have shown that the use of personal computer systems in commercial office buildings is expanding rapidly. The energy consumption of such a growing end-use also has a significant impact on the total building power demand. In warmer climates, office equipment energy use has important implications for building cooling loads as well as those directly associated with computing tasks. Recently, …


Daylighting Dimming And Energy Savings: The Effects Of Window Orientation And Blinds, Florida Solar Energy Center, Lynn Schrum Apr 1996

Daylighting Dimming And Energy Savings: The Effects Of Window Orientation And Blinds, Florida Solar Energy Center, Lynn Schrum

FSEC Energy Research Center®

The Daylighting Test Facility (DTF) located at Florida Solar Energy Center, was used to study daylight dimming systems and how orientation and blinds effect energy savings. To evaluate the impact of blinds on dimming savings, the energy consumption was compared in two pairs of offices for all four window orientations: north, south, east and west. One office in each pair had blinds in a fixed position (down and open) and the other office had no blinds. From September through December of 1994, data were collected on the north- and south-facing offices. The DTF was rotated 90 degrees and data were …


Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young Apr 1996

Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Hurricanes, floods, tornadoes, earthquakes, and other disasters can happen at any time, often with little or no advance warning. They can be as destructive as Hurricane Andrew leaving several hundred-thousand people homeless or as minor as an afternoon thunderstorm knocking down local power lines to your home. Major disasters leave many people without adequate medical services, portable water, electrical service and communications. In response to a natural disaster, photovoltaic (solar electric) modules offer a source of quite, safe, pollution-free electrical power. Photovoltaic (PV) power systems are capable of providing the electrical needs for vaccine refrigerators, microscopes, medical equipment, lighting, radios, …


Uncontrolled Air Flow In Non-Residential Buildings, Florida Solar Energy Center, James Cummings Mar 1996

Uncontrolled Air Flow In Non-Residential Buildings, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

The objective of this study was to develop the capability to substantially reduce energy use, building degradation and indoor air pollution caused by uncontrolled air flow in nonresidential buildings. For purposes of the study, 'uncontrolled air flow' was defined as air moving across the building envelope or between zones or components of a building, where the pathways of flow, the direction of flow, and the origin of the air are unknown, unspecified, or unintended. The study comes to three major conclusions as follows: 1. Uncontrolled air flow is pervasive in buildings, often resulting in severe -- and sometimes even catastrophic …


Test 1633: Valmet 8550 Diesel, Nebraska Tractor Test Lab Jan 1996

Test 1633: Valmet 8550 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.


Test 1710: Case Ih 7230 Diesel 18-Speed (Chassis S/N Jja0065000 And Higher), Nebraska Tractor Test Lab Jan 1996

Test 1710: Case Ih 7230 Diesel 18-Speed (Chassis S/N Jja0065000 And Higher), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE

General

Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure.

The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Test 1711: Case Ih 7240 Diesel 18-Speed (Chassis S/N Jja 0065000 And Higher), Nebraska Tractor Test Lab Jan 1996

Test 1711: Case Ih 7240 Diesel 18-Speed (Chassis S/N Jja 0065000 And Higher), Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE

General

Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure.

The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Nebraska Summary: S220 New Holland 8870, Nebraska Tractor Test Lab Jan 1996

Nebraska Summary: S220 New Holland 8870, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Lai - Introduction To Continuum Mechanics ترجمه فارسي کتاب مکانيک محيط پيوسته ويرايش سوم, Dr Alireza Zolfaghari Jan 1996

Lai - Introduction To Continuum Mechanics ترجمه فارسي کتاب مکانيک محيط پيوسته ويرايش سوم, Dr Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.


Termes De Signes Positif Et Négatif En Analyses Exergétiques Des Flux De Chaleur, Jim Mcgovern, Pierre Le Goff Jan 1996

Termes De Signes Positif Et Négatif En Analyses Exergétiques Des Flux De Chaleur, Jim Mcgovern, Pierre Le Goff

Articles

In various technical plants there are heat transfer rates at temperatures above that of the environment and other simultaneous heat transfer rates at temperatures below the temperature of the environment. This is the case in cryogenic industrial processes where a cooling effect is produced from a heat source. This is also the case for all absorption refrigeration plants or absorption plants that provide refrigeration and heat pumping, notably for air-conditioning of buildings. In these cases exergetic analysis leads to equations in which some terms are positive and others are negative. This can pose problems in the definition of exergetic, or …


An Interdisciplinary Solar Energy Project, William J. Hutzel Jan 1996

An Interdisciplinary Solar Energy Project, William J. Hutzel

School of Engineering Technology Faculty Publications

An HVAC course, previously offered to students in Mechanical Engineering Technology (MET), has been re-structured to include students in Building Construction Management (BCM). A large project is always an integral part of this course, creating a unique opportunity for collaboration between two distinctly different groups of Technology students. This cooperation is particularly beneficial because MET and BCM graduates frequently cross paths during their professional careers. Many MET graduates operate and service heating, ventilating, and air conditioning equipment that was originally specified and installed by BCM graduates. This paper discusses and evaluates student interactions during a solar …


Energy Savings From Repair Of Uncontrolled Airflow In Eighteen Small Commercial Buildings, Florida Solar Energy Center, Charles Withers, Jr. Jan 1996

Energy Savings From Repair Of Uncontrolled Airflow In Eighteen Small Commercial Buildings, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Uncontrolled airflow, including duct leakage, pressure imbalances caused by closed interior doors, and exhaust/intake airflow imbalance, was characterized in 70 commercial buildings. In 18 of these buildings, uncontrolled airflows were repaired and energy savings from these repairs were monitored. In most buildings the retrofit was duct repair. In other cases, outdoor airflow was reduced and return air transfers were provided. Cooling energy use was reduced by an average 15.1% in these 18 buildings. With an average repair cost of $455 and average cooling energy savings of $195 per year, uncontrolled airflow retrofits proved to be very cost-effective. Various factors indicate …


Nebraska Summary: S297 Valmet 8550, Nebraska Tractor Test Lab Jan 1996

Nebraska Summary: S297 Valmet 8550, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S251 New Holland 8360, Nebraska Tractor Test Lab Jan 1996

Nebraska Summary: S251 New Holland 8360, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S249 New Holland 8260, Nebraska Tractor Test Lab Jan 1996

Nebraska Summary: S249 New Holland 8260, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S221 New Holland 8970, Nebraska Tractor Test Lab Jan 1996

Nebraska Summary: S221 New Holland 8970, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S218 New Holland 8670, Nebraska Tractor Test Lab Jan 1996

Nebraska Summary: S218 New Holland 8670, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S217 White 6045, Nebraska Tractor Test Lab Jan 1996

Nebraska Summary: S217 White 6045, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …