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Effects of Multiaxial Stretching on Crazing and Other Properties of Transparent Plastics

Description: Memorandum presenting an investigation of the effects of orientation by multi-axial stretching on properties of various plastic glazing materials. The materials studied were Lucite HC-222, Plexiglass 55, Gafite, and resin C. Some of the tests conducted included dimensional stability at elevated temperatures, surface abrasion, standard tensile tests, and stress-solvent crazing tests using ethylene dichloride.
Date: October 20, 1954
Creator: Wolock, Irvin & George, Desmond A.
Partner: UNT Libraries Government Documents Department

Modeling Windows in Energy Plus with Simple Performance Indices

Description: The building energy simulation program, Energy Plus (E+), cannot use standard window performance indices (U, SHGC, VT) to model window energy impacts. Rather, E+ uses more accurate methods which require a physical description of the window. E+ needs to be able to accept U and SHGC indices as window descriptors because, often, these are all that is known about a window and because building codes, standards, and voluntary programs are developed using these terms. This paper outlines a procedure, developed for E+, which will allow it to use standard window performance indices to model window energy impacts. In this 'Block' model, a given U, SHGC, VT are mapped to the properties of a fictitious 'layer' in E+. For thermal conductance calculations, the 'Block' functions as a single solid layer. For solar optical calculations, the model begins by defining a solar transmittance (Ts) at normal incidence based on the SHGC. For properties at non-normal incidence angles, the 'Block' takes on the angular properties of multiple glazing layers; the number and type of layers defined by the U and SHGC. While this procedure is specific to E+, parts of it may have applicability to other window/building simulation programs.
Date: October 12, 2009
Creator: Arasteh, Dariush; Kohler, Christian & Griffith, Brent
Partner: UNT Libraries Government Documents Department

Highly Insulating Glazing Systems using Non-Structural Center Glazing Layers

Description: Three layer insulating glass units with two low-e coatings and an effective gas fill are known to be highly insulating, with center-of-glass U-factors as low as 0.57 W/m{sup 2}-K (0.10 Btu/h-ft{sup 2}- F). Such units have historically been built with center layers of glass or plastic which extend all the way through the spacer system. This paper shows that triple glazing systems with non-structural center layers which do not create a hermetic seal at the edge have the potential to be as thermally efficient as standard designs, while potentially removing some of the production and product integration issues that have discouraged the use of triples.
Date: April 9, 2008
Creator: Kohler, Christian; Arasteh, Dariush; Goudey, Howdy & Kohler, Christian
Partner: UNT Libraries Government Documents Department

Focused R&D For Electrochromic Smart Windowsa: Significant Performance and Yield Enhancements

Description: There is a need to improve the energy efficiency of building envelopes as they are the primary factor governing the heating, cooling, lighting and ventilation requirements of buildings--influencing 53% of building energy use. In particular, windows contribute significantly to the overall energy performance of building envelopes, thus there is a need to develop advanced energy efficient window and glazing systems. Electrochromic (EC) windows represent the next generation of advanced glazing technology that will (1) reduce the energy consumed in buildings, (2) improve the overall comfort of the building occupants, and (3) improve the thermal performance of the building envelope. ''Switchable'' EC windows provide, on demand, dynamic control of visible light, solar heat gain, and glare without blocking the view. As exterior light levels change, the window's performance can be electronically adjusted to suit conditions. A schematic illustrating how SageGlass{reg_sign} electrochromic windows work is shown in Figure I.1. SageGlass{reg_sign} EC glazings offer the potential to save cooling and lighting costs, with the added benefit of improving thermal and visual comfort. Control over solar heat gain will also result in the use of smaller HVAC equipment. If a step change in the energy efficiency and performance of buildings is to be achieved, there is a clear need to bring EC technology to the marketplace. This project addresses accelerating the widespread introduction of EC windows in buildings and thus maximizing total energy savings in the U.S. and worldwide. We report on R&D activities to improve the optical performance needed to broadly penetrate the full range of architectural markets. Also, processing enhancements have been implemented to reduce manufacturing costs. Finally, tests are being conducted to demonstrate the durability of the EC device and the dual pane insulating glass unit (IGU) to be at least equal to that of conventional windows.
Date: January 31, 2003
Creator: Burdis, Mark & Sbar, Neil
Partner: UNT Libraries Government Documents Department

Electrochromic Windows: Process and Fabrication Improvements for Lower Total Costs

Description: The overall goal with respect to the U.S. Department of Energy (DOE) is to achieve significant national energy savings through maximized penetration of EC windows into existing markets so that the largest cumulative energy reduction can be realized. The speed with which EC windows can be introduced and replace current IGU's (and current glazings) is clearly a strong function of cost. Therefore, the aim of this project was to investigate possible improvements to the SageGlass{reg_sign} EC glazing products to facilitate both process and fabrication improvements resulting in lower overall costs. The project was split into four major areas dealing with improvements to the electrochromic layer, the capping layer, defect elimination and general product improvements. Significant advancements have been made in each of the four areas. These can be summarized as follows: (1) Plasma assisted deposition for the electrochromic layer was pursued, and several improvements made to the technology for producing a plasma beam were made. Functional EC devices were produced using the new technology, but there are still questions to be answered regarding the intrinsic properties of the electrochromic films produced by this method. (2) The capping layer work was successfully implemented into the existing SageGlass{reg_sign} product, thereby providing a higher level of transparency and somewhat lower reflectivity than the 'standard' product. (3) Defect elimination is an ongoing effort, but this project spurred some major defect reduction programs, which led to significant improvements in yield, with all the implicit benefits afforded. In particular, major advances were made in the development of a new bus bar application process aimed at reducing the numbers of 'shorts' developed in the finished product, as well as making dramatic improvements in the methods used for tempering the glass, which had previously been seen to produce a defect which appeared as a pinhole. (4) Improvements have ...
Date: March 31, 2007
Creator: Burdis, Mark & Sbar, Neil
Partner: UNT Libraries Government Documents Department

Florida Solar Energy Center: Final report 1996

Description: A small research group at the Florida Solar Energy Center has been working for several years to perform research and other work in support of U.S. Department of Energy and State of Florida energy efficiency objectives in the area of windows, skylights, clerestories, and other glazed apertures in buildings, generically called fenestrations. This work includes not only thermal energy transfer through fenestration systems but also the controlled introduction of daylight illumination for the displacement of electric lighting energy. Work in the last few years has focused almost entirely on providing technical support to the National Fenestration Rating Council`s program to introduce energy performance rating and labelling of windows into the United States. This work has included a variety of activities. (1) Annual energy performance simulations aimed at determining the relative performances of a variety of residential window and glazing options for different climates. (2) Evaluation of Lawrence Berkeley Laboratory reports and software products in the area of fenestrations. (3) Development of better computational tools for predicting the solar spectral irradiance incident on fenestration systems and contributing to solar radiant heat gain, and the effects of exterior shading. (4) Service on various committees and task groups of the NFRC as well as participation in and technical support for ASHRAE`s technical committee 4.5 on fenestrations. (5) Evaluation of the daylighting potential of commercial buildings in hot humid climates.
Date: July 18, 1996
Partner: UNT Libraries Government Documents Department

Architectural Surety Applications for Building Response to Dynamic Loads

Description: This paper provides a summary introduction to the emerging area of Architectural Surety{trademark} applications for buildings and infrastructures that are subjected to dynamic loads from blast and naturally occurring events. This technology area has been under investigation to assist with the definition of risks associated with dynamic loads and to provide guidance for determining the required upgrading and retrofitting techniques suggested for reducing building and infrastructure vulnerabilities to such dynamic forces. This unique approach involves the application of risk management techniques for solving problems of the as-built environment through the application of security, safety, and reliability principles developed in the nuclear weapons programs of the United States Department of Energy (DOE) and through the protective structures programs of the German Ministry of Defense (MOD). The changing responsibilities of engineering design professionals are addressed in light of the increased public awareness of structural and facility systems' vulnerabilities to malevolent, normal, and abnormal environment conditions. Brief discussions are also presented on (1) the need to understand how dynamic pressures are affected by the structural failures they cause, (2) the need to determine cladding effects on columns, walls, and slabs, and (3) the need to establish effective standoff distance for perimeter barriers. A summary description is presented of selected technologies to upgrade and retrofit buildings by using high-strength concrete and energy-absorbing materials and by specifying appropriately designed window glazing and special masonry wall configurations and composites. The technologies, material performance, and design evaluation procedures presented include super-computational modeling and structural simulations, window glass fragmentation modeling, risk assessment procedures, instrumentation and health monitoring systems, three-dimensional CAD virtual reality visualization techniques, and material testing data.
Date: February 10, 1999
Creator: Matalucci, R.V. & Mayrhofer, C.
Partner: UNT Libraries Government Documents Department

Optical properties of glazing materials at normal incidence

Description: Measurements of spectral transmittance T and reflectance R at normal incidence continue to be the most common and accurate source of energy performance data for glazing materials. Prediction of these radiometric properties from more fundamental materials data is often confounded by the complexity and uncertainty of coating structures. Angle-dependent radiometric properties of coated glazing will probably be predicted from normal-incidence data rather than being measured at many angles. The general error level demonstrated in round-robin tests is on the order 1-2%; it is often necessary to achieve better levels of performance. Based on results obtained following the round-robin tests, it is expected that accuracy of better than 0.5% can be generally achieved. A new type of absolute standard reference is described and tested with promising results.
Date: October 1, 2001
Creator: Rubin, M. & Powles, R.
Partner: UNT Libraries Government Documents Department

Solar heat gain through fenestration systems containing shading: Summary of procedures for estimating performance from minimal data

Description: The computational methods for calculating the properties of glazing systems containing shading from the properties of their components have been developed, but the measurement standards and property data bases necessary to apply them have not. It is shown that with a drastic simplifying assumption these methods can be used to calculate system solar-optical properties and solar heat gain coefficients for arbitrary glazing systems, while requiring limited data about the shading. Detailed formulas are presented, and performance multipliers are defined for the approximate treatment of simple glazings with shading. As higher accuracy is demanded, the formulas become very complicated.
Date: March 1, 2001
Creator: Klems, Joseph H.
Partner: UNT Libraries Government Documents Department

A characterization of the nonresidential fenestration market

Description: The purpose of this report is to characterize the nonresidential fenestration market in order to better understand market barriers to, and opportunities for, energy-efficient fenestration products. In particular, the goal is to: (1) Better understand how glazing products flow between industry groups. (2) Identify major decision makers directing the product flow. (3) Understand industry trends for certain technologies or products. (4) Characterize the role of energy codes and standards in influencing industry trends. (5) Assess the impact of product testing and certification programs on the industry. The U.S. glass industry is a $27 billion enterprise with both large producers and small firms playing pivotal roles in the industry. While most sectors of the glass industry have restructured and consolidated in the past 20 years, the industry still employs 150,000 workers. Nonresidential glazing accounts for approximately 18% of overall U.S. glass production. In 1999, nonresidential glazing was supplied to approximately 2.2 billion ft{sup 2} of new construction and additions. That same year, nonresidential glazing was also supplied to approximately 1.1 billion ft{sup 2} of remodeling construction. With an industry this large and complex, it is to be expected that many market participants can influence fenestration selection. If market barriers to the selection of high performance fenestration products are better understood, then the U. S. Department of Energy (USDOE), the Northwest Energy Efficiency Alliance (NEEA), and others can develop programs and policies that promote greater energy efficiency in commercial glazing products.
Date: July 25, 2002
Creator: Shehabi, Arman; Eley, Charles; Arasteh, Dariush & Degens, Phil
Partner: UNT Libraries Government Documents Department

Solar Heat Gain Through Fenestration Systems Containing Shading: Procedures for Estimating Performance from Minimal Data

Description: The computational methods for calculating the properties of glazing systems containing shading from the properties of their components have been developed, but the measurement standards and property data bases necessary to apply them have not. It is shown that with a drastic simplifying assumption these methods can be used to calculate system solar-optical properties and solar heat gain coefficients for arbitrary glazing systems, while requiring limited data about the shading. Detailed formulas are presented, and performance multipliers are defined for the approximate treatment of simple glazings with shading. As higher accuracy is demanded, the formulas become very complicated.
Date: August 1, 2000
Creator: Klems, J.H.
Partner: UNT Libraries Government Documents Department

Establishing the value of advanced glazings

Description: Numerous glazing technologies are under development worldwide to improve the performance of building facades. High-performance glazings can provide substantial energy and related environmental benefits, but often at greatly increased first cost when compared to conventional design solutions. To increase market viability, we discuss strategies to reduce the actual and owner-perceived costs associated with developing and producing advanced window systems, specifically switchable electrochromic glazings, and we also suggest marketing strategies designed to appeal to early adopter and mainstream purchasers. These strategies may be applicable to a broad range of advanced glazing materials.
Date: January 1, 1999
Creator: Lee, E & Selkowitz, S.
Partner: UNT Libraries Government Documents Department

Advances in Glazing Materials for Windows

Description: No one type of glazing is suitable for every application. Many materials are available that serve different purposes. Moreover, consumers may discover that they need two types of glazing for a home because of the directions that the windows face and the local climate. To make wise purchases, consumers should first examine their heating and cooling needs and prioritize desired features such as daylighting, solar heating, shading, ventilation, and aesthetic value. Research and development into types of glazing have created a new generation of materials that offer improved window efficiency and performance for consumers. While this new generation of glazing materials quickly gains acceptance in the marketplace, the research and development of even more efficient technology continues.
Date: November 1994
Partner: UNT Libraries Government Documents Department

Light-scattering properties of a woven shade-screen material used for daylighting and solar heat-gain control

Description: Shade-screens are widely used in commercial buildings as a way to limit the amount of direct sunlight that can disturb people in the building. The shade screens also reduce the solar heat-gain through glazing the system. Modern energy and daylighting analysis software such as EnergyPlus and Radiance require complete scattering properties of the scattering materials in the system. In this paper a shade screen used in the LBNL daylighting testbed is characterized using a photogoniometer and a normal angle of incidence integrating sphere. The data is used to create a complete bi-directional scattering distribution function (BSDF) that can be used in simulation programs. The resulting BSDF is compared to a model BADFs, both directly and by calculating the solar heat-gain coefficient for a dual pane system using Window 6.
Date: August 1, 2008
Creator: Jonsson, Jacob; Jonsson, Jacob C.; Lee, Eleanor S. & Rubin, Mike
Partner: UNT Libraries Government Documents Department

Development and testing of a photometric method to identify non-operating solar hot water systems in field settings.

Description: This report presents the results of experimental tests of a concept for using infrared (IR) photos to identify non-operational systems based on their glazing temperatures; operating systems have lower glazing temperatures than those in stagnation. In recent years thousands of new solar hot water (SHW) systems have been installed in some utility districts. As these numbers increase, concern is growing about the systems dependability because installation rebates are often based on the assumption that all of the SHW systems will perform flawlessly for a 20-year period. If SHW systems routinely fail prematurely, then the utilities will have overpaid for grid-energy reduction performance that is unrealized. Moreover, utilities are responsible for replacing energy for loads that failed SHW system were supplying. Thus, utilities are seeking data to quantify the reliability of SHW systems. The work described herein is intended to help meet this need. The details of the experiment are presented, including a description of the SHW collectors that were examined, the testbed that was used to control the system and record data, the IR camera that was employed, and the conditions in which testing was completed. The details of the associated analysis are presented, including direct examination of the video records of operational and stagnant collectors, as well as the development of a model to predict glazing temperatures and an analysis of temporal intermittency of the images, both of which are critical to properly adjusting the IR camera for optimal performance. Many IR images and a video are presented to show the contrast between operating and stagnant collectors. The major conclusion is that the technique has potential to be applied by using an aircraft fitted with an IR camera that can fly over an area with installed SHW systems, thus recording the images. Subsequent analysis of the images can determine ...
Date: June 1, 2012
Creator: He, Hongbo (University of New Mexico, Albuquerque, NM); Vorobieff, Peter V. (University of New Mexico, Albuquerque, NM); Menicucci, David (University of New Mexico, Albuquerque, NM); Mammoli, Andrea A. (University of New Mexico, Albuquerque, NM) & Carlson, Jeffrey J.
Partner: UNT Libraries Government Documents Department

Fenestration System Performance Research, Testing, and Evaluation

Description: The US DOE was and is instrumental to NFRC's beginning and its continued success. The 2005 to 2009 funding enables NFRC to continue expanding and create new, improved ratings procedures. Research funded by the US DOE enables increased fenestration energy rating accuracy. International harmonization efforts supported by the US DOE allow the US to be the global leader in fenestration energy ratings. Many other governments are working with the NFRC to share its experience and knowledge toward development of their own national fenestration rating process similar to the NFRC's. The broad and diverse membership composition of NFRC allows anyone with a fenestration interest to come forward with an idea or improvement to the entire fenestration community for consideration. The NFRC looks forward to the next several years of growth while remaining the nation's resource for fair, accurate, and credible fenestration product energy ratings. NFRC continues to improve its rating system by considering new research, methodologies, and expanding to include new fenestration products. Currently, NFRC is working towards attachment energy ratings. Attachments are blinds, shades, awnings, and overhangs. Attachments may enable a building to achieve significant energy savings. An NFRC rating will enable fair competition, a basis for code references, and a new ENERGY STAR product category. NFRC also is developing rating methods to consider non specular glazing such as fritted glass. Commercial applications frequently use fritted glazing, but no rating method exists. NFRC is testing new software that may enable this new rating and contribute further to energy conservation. Around the world, many nations are seeking new energy conservation methods and NFRC is poised to harmonize its rating system assisting these nations to better manage and conserve energy in buildings by using NFRC rated and labeled fenestration products. As this report has shown, much more work needs to be done ...
Date: November 30, 2009
Creator: Benney, Jim
Partner: UNT Libraries Government Documents Department

Low-cost solar room kit. Final grant report

Description: A low cost solar room kit was developed which would make use of local framing materials, but provide inexperienced builders with a simple joining system and materials - such as glazings - not usually available in local stores. Since solar room applications are proven effective in providing supplementary home heat, a kit would make solar heat more accessible to home owners and tenants. Although a prototype and two working models of the kit were successfully built, commercial development cannot occur until problems in matching the glazing and framing system can be resolved, and more capital to lower production costs on the framing union pieces is available.
Date: unknown
Partner: UNT Libraries Government Documents Department

The national energy requirements of residential windows in the U.S.: Today and tomorrow

Description: This paper describes an end-use analysis of the national energy requirements of US residential window technologies. The authors estimate that the current US stock of 19 billion square feet of residential windows is responsible for 1.7 quadrillion BTUs (or quads) per year of energy use--1.3 quads of heating and 0.4 quads of cooling energy--which represents about 2% of total US energy consumption. They show that national energy use due to windows could be reduced by 25% by the year 2010 through accelerated adoption of currently available, advanced window technologies such as low-e and solar control low-e coatings, vinyl and wood frames, and superwindows. The authors evaluate the economics of the technologies regionally, considering both climatic and energy price variations, and find that the technologies would be cost effective for most consumers.
Date: March 1, 1996
Creator: Frost, K.; Eto, J.; Arasteh, D. & Yazdanian, M.
Partner: UNT Libraries Government Documents Department

Solar electric buildings: An overview of today`s applications

Description: This brochure presents a broad look at photovoltaic-powered buildings. It includes residential and commercial systems, both stand-alone and connected to utility power, that are located in urban, near-urban, and rural settings around the world. As photovoltaic (PV) technology continues to improve and costs drop, opportunities for PV will multiply. PV systems for buildings, such as those shown here, represent one of the strongest near-term markets.
Date: February 1, 1997
Partner: UNT Libraries Government Documents Department

Optical Data Library {number_sign}5 for use with the WINDOW 4.1 computer program including NFRC certified data

Description: This report contains additional data for 783 glazing products that can be used with the Window 4.1 energy analysis program. The NFRC requires that all simulations must be carried out using NFRC-certified optical data only. Solar heat gain coefficient and visible transmittance must be calculated using spectral transmittance and reflectance in the solar range. U-factor calculations must use spectral or integrated emittance. NFRC-certified data within the Window 4.1 program is indicated.
Date: January 1, 1998
Creator: Rubin, M.
Partner: UNT Libraries Government Documents Department

Design and evaluation of daylighting applications of holographic glazings

Description: According to the contractual agreement, BTP would develop a computer model of the POC holographic structures and then simulate the performance of alternative designs using the RADIANCE lighting and rendering computer program [Ward 1990]. The RADIANCE model would then be used to evaluate the daylight performance of alternative designs of holographic glazings in a prototypical office space. The simulation process would be validated against actual photometric measurements of holographic glazing samples developed by POC. The results would be used to evaluate the potential for increased electric lighting savings through increased daylight illuminance levels at distances more than 15 ft--20 ft (4.6 m--6.1 m ) from the window wall.
Date: December 1, 1996
Creator: Papamichael, K.; Ehrlich, C. & Ward, G.
Partner: UNT Libraries Government Documents Department

Spectrally selective glazings

Description: Spectrally selective glazing is window glass that permits some portions of the solar spectrum to enter a building while blocking others. This high-performance glazing admits as much daylight as possible while preventing transmission of as much solar heat as possible. By controlling solar heat gains in summer, preventing loss of interior heat in winter, and allowing occupants to reduce electric lighting use by making maximum use of daylight, spectrally selective glazing significantly reduces building energy consumption and peak demand. Because new spectrally selective glazings can have a virtually clear appearance, they admit more daylight and permit much brighter, more open views to the outside while still providing the solar control of the dark, reflective energy-efficient glass of the past. This Federal Technology Alert provides detailed information and procedures for Federal energy managers to consider spectrally selective glazings. The principle of spectrally selective glazings is explained. Benefits related to energy efficiency and other architectural criteria are delineated. Guidelines are provided for appropriate application of spectrally selective glazing, and step-by-step instructions are given for estimating energy savings. Case studies are also presented to illustrate actual costs and energy savings. Current manufacturers, technology users, and references for further reading are included for users who have questions not fully addressed here.
Date: August 1, 1998
Partner: UNT Libraries Government Documents Department