02585nas a2200205 4500008004100000245005400041210005100095260006100146300001000207520191200217100002002129700002202149700002202171700002302193700002502216700002202241700001602263700002402279856007602303 2008 eng d00aWINDOW 6.2/THERM 6.2 Research Version User Manual0 aWINDOW 62THERM 62 Research Version User Manual aBerkeleybLawrence Berkeley National Laboratoryc01/2008 a1-1263 a
WINDOW 6 and THERM 6 Research Versions are software programs developed at Lawrence Berkeley National Laboratory (LBNL) for use by manufacturers, engineers, educators, students, architects, and others to determine the thermal and solar optical properties of glazing and window systems.
WINDOW 6 and THERM 6 are significant updates to LBNL's WINDOW 5 and THERM 5 computer program because of the added capability to model complex glazing systems, such as windows with shading systems, in particular venetian blinds. Besides a specific model for venetian blinds and diffusing layers, WINDOW 6 also includes the generic ability to model any complex layer if the Transmittance and Reflectance are known as a function of incoming and outgoing angles.
The algorithms used in these versions of the programs to determine the properties of windows with shading layers are relatively new and should be considered as informative but not definitive.
As such, for windows with shading layers, the results are intended for research purposes only. Pending further validation efforts, results for windows with sh ading layers should not be used for NFRC certified calculations of design decisions in real buildings.
All calculations for products without shading layers are identical to those from WINDOW 5.2.
WINDOW 6 Research Version includes all of the WINDOW 5 capabilities with the addition of shading algorithms from ISO15099 which are incorporated into the program, as well as an extension of those algorithms with the matrix calculation method.
THERM 6 Research Version includes all of the THERM 5 capabilities with the addition of being able to import and model WINDOW 6 glazing systems with shading devices. Those THERM 6 files with shading devices can them be imported into the WINDOW 6 Frame Library and whole windows with shading devices can then be modeled in WINDOW 6.
1 aMitchell, Robin1 aKohler, Christian1 aKlems, Joseph, H.1 aRubin, Michael, D.1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aYu, Tiefeng1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/window-62therm-62-research-version01885nas a2200169 4500008004100000050001500041245008600056210006900142260002700211520128600238100002501524700002401549700001901573700002201592700002201614856007901636 2006 eng d aLBNL-6124900aEvaluating Fenestration Products for Zero-Energy Buildings: Issues for Discussion0 aEvaluating Fenestration Products for ZeroEnergy Buildings Issues aCambridge, MAc08/20063 aComputer modeling to determine fenestration product energy properties (U-factor, SHGC, VT) has emerged as the most cost-effective and accurate means to quantify them. Fenestration product simulation tools have been effective in increasing the use of low-e coatings and gas fills in insulating glass and in the widespread use of insulating frame designs and materials. However, for more efficient fenestration products (low heat loss products, dynamic products, products with non-specular optical characteristics, light redirecting products) to achieve widespread use, fenestration modeling software needs to be improved.
This paper addresses the following questions:
1) Are the current properties (U, SHGC, VT) calculated sufficient to compare and distinguish between windows suitable for Zero Energy Buildings and conventional window products? If not, what data on the thermal and optical performance, on comfort, and on peak demand of windows is needed.
2) Are the algorithms in the tools sufficient to model the thermal and optical processes? Are specific heat transfer and optical effects not accounted for? Is the existing level of accuracy enough to distinguish between products designed for Zero Energy Buildings? Is the current input data adequate?
1 aArasteh, Dariush, K.1 aCurcija, Dragan, C.1 aHuang, Yu, Joe1 aHuizenga, Charlie1 aKohler, Christian uhttps://facades.lbl.gov/publications/evaluating-fenestration-products-zero01869nas a2200157 4500008004100000245003300041210003200074260005100106520137600157100002001533700001901553700002501572700002201597700002301619856006901642 2005 eng d00aRESFEN5: Program Description0 aRESFEN5 Program Description bLawrence Berkeley National Laboratoryc05/20053 aA computer tool such as RESFEN can help consumers and builders pick the most energy-efficient and cost-effective window for a given application, whether it is a new home, an addition, or a window replacement. It calculates heating and cooling energy use and associated costs as well as peak heating and cooling demand for specific window products. Users define a specific scenario by specifying house type (single-story or two-story), geographic location, orientation, electricity and gas cost, and building configuration details (such as wall, floor, and HVAC system type). Users also specify size, shading, and thermal properties of the window they wish to investigate. The thermal properties that RESFEN requires are: U-factor, Solar Heat Gain Coefficient, and air leakage rate. RESFEN calculates the energy and cost implications of the window compared to an insulated wall. The relative energy and cost impacts of two different windows can be compared.
RESFEN 3.0 was a major improvement over previous versions because it performs hourly calculations using a version of the DOE 2.1E (LBL 1980, Winkelmann et al. 1993) energy analysis simulation program. RESFEN 3.1 incorporates additional improvements including input assumptions for the base case buildings taken from the National Fenestration Rating Council (NFRC) Annual Energy Subcommittee's efforts.
1 aMitchell, Robin1 aHuang, Yu, Joe1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aGlendenning, Steve uhttps://facades.lbl.gov/publications/resfen5-program-description01448nas a2200169 4500008004100000050001500041245004400056210004300100520093100143100002001074700002201094700002501116700001801141700002201159700002401181856007301205 2003 eng d aLBNL-4825500aTHERM 5/WINDOW 5 NFRC Simulation Manual0 aTHERM 5WINDOW 5 NFRC Simulation Manual3 aThis document, the THERM 5 / WINDOW 5 NFRC Simulation Manual, discusses how to use the THERM and WINDOW programs to model products for NFRC certified simulations and assumes that the user is already familiar with those programs. In order to learn how to use these programs, it is necessary to become familiar with the material in both the THERM Users Manual and the WINDOW Users Manual. In general, this manual references the Users Manuals rather than repeating the information.
If there is a conflict between either of the User Manual and this THERM 5 / WINDOW 5 NFRC Simulation Manual, the THERM 5 / WINDOW 5 NFRC Simulation Manual takes precedence. In addition, if this manual is in conflict with any NFRC standards, the standards take precedence. For example, if samples in this manual do not follow the current taping and testing NFRC standards, the standards not the samples in this manual, take precedence.
1 aMitchell, Robin1 aKohler, Christian1 aArasteh, Dariush, K.1 aCarmody, John1 aHuizenga, Charlie1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/therm-5window-5-nfrc-simulation02156nas a2200169 4500008004100000050001500041245008000056210006900136260003400205520156000239100002501799700002001824700002201844700002201866700002401888856007401912 2001 eng d aLBNL-4814700aImproving Information Technology to Maximize Fenestration Energy Efficiency0 aImproving Information Technology to Maximize Fenestration Energy aClearwater Beach, FLc12/20013 aAnnual heating and cooling energy loads through fenestration products in both residential and commercial buildings are a significant fraction of national energy requirements. In the residential sector, 1.34 and 0.37 quads are required for heating and cooling respectively (DOE Core Data Book, 2000). In commercial buildings, cooling energy use to compensate for fenestration product solar heat gain is estimated at 0.39 quads; heating energy use to compensate for heat loss through fenestration products is estimated at 0.19 quads. Advanced products offer the potential to reduce these energy uses by at least 50% (Frost et. al. 1993). Potential electric lighting savings from fenestration products are estimated at 0.4 quads if daylight can be used effectively so that electric lighting in commercial building perimeter zones can be reduced.
Software has begun to make an impact on the design and deployment of efficient fenestration products by making fenestration product performance ratings widely available. These ratings, which are determined in part using software programs such as WINDOW/THERM/Optics, VISION/FRAME, and WIS, can now easily be used by architects, engineers, professional fenestration product specifiers, and consumers. Information on the properties of fenestration products has also influenced state and national codes (IECC, ASHRAE 90.1) and aided voluntary market transformation programs, such as the Efficient Windows Collaborative and the Energy Star Windows program, which promote efficient fenestration products.
1 aArasteh, Dariush, K.1 aMitchell, Robin1 aKohler, Christian1 aHuizenga, Charlie1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/improving-information-technology00496nas a2200133 4500008004100000245006800041210006700109100002000176700002200196700002500218700002200243700002400265856007300289 2001 eng d00aWINDOW 5.0 User Manual for Analyzing Window Thermal Performance0 aWINDOW 50 User Manual for Analyzing Window Thermal Performance1 aMitchell, Robin1 aKohler, Christian1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/window-50-user-manual-analyzing01204nas a2200193 4500008004100000245003700041210003600078260001200114300000800126520064300134100002000777700002200797700002500819700002900844700002200873700002400895700001800919856007300937 2000 eng d00aTHERM 2.1 NFRC Simulation Manual0 aTHERM 21 NFRC Simulation Manual c07/2000 a2603 aThis document, the THERM 2.1 NFRC Simulation Manual, discusses how to use THERM to model products for NFRC certified simulations and assumes that the user is already familiar with the THERM program. In order to learn how to use THERM, it is necessary to become familiar with the material in the THERM User's Manual.
In general, this manual references the THERM User's Manual rather than repeating the information.
If there is a conflict between the THERM User's Manual and the THERM 2.1 NFRC Simulation Manual, the THERM 2.1 NFRC Simulation Manual takes precedence.
1 aMitchell, Robin1 aKohler, Christian1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aHuizenga, Charlie1 aCurcija, Dragan, C.1 aCarmody, John uhttps://facades.lbl.gov/publications/therm-21-nfrc-simulation-manual01203nas a2200181 4500008004100000050001500041245008900056210006900145260002600214520056200240100002200802700002500824700002900849700002000878700002400898700002400922856007500946 1999 eng d aLBNL-4399100aTHERM 2.0: A Building Component Model for Steady-State Two-Dimensional Heat Transfer0 aTHERM 20 A Building Component Model for SteadyState TwoDimension aKyoto, Japanc09/19993 aTHERM 2.0 is a state-of-the-art software program, available without cost, that uses the finite-element method to model steady-state, two-dimensional heat-transfer problems. It includes a powerful simulation engine combined with a simple, interactive interface and graphic results. Although it was developed primarily to model thermal properties of windows, it is appropriate for other building components such as walls, doors, roofs, and foundations, and is useful for modeling thermal bridges in many other contexts, such as the design of equipment.
1 aHuizenga, Charlie1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aMitchell, Robin1 aGriffith, Brent, T.1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/therm-20-building-component-model02194nas a2200181 4500008004100000050001500041245007900056210006900135260003100204520156500235100002501800700002901825700001901854700002201873700002001895700002301915856007401938 1998 eng d aLBNL-4215100aState-of-the-Art Software for Window Energy-Efficiency Rating and Labeling0 aStateoftheArt Software for Window EnergyEfficiency Rating and La aPacific Grove, CAc08/19983 aMeasuring the thermal performance of windows in typical residential buildings is an expensive proposition. Not only is laboratory testing expensive, but each window manufacturer typically offers hundreds of individual products, each of which has different thermal performance properties. With over a thousand window manufacturers nationally, a testing-based rating system would be prohibitively expensive to the industry and to consumers.
Beginning in the early 1990s, simulation software began to be used as part of a national program for rating window U-values. The rating program has since been expanded to include Solar Hear Gain Coefficients and is now being extended to annual energy performance.
This paper describes four software packages available to the public from Lawrence Berkeley National Laboratory (LBNL). These software packages are used to evaluate window thermal performance: RESFEN (for evaluating annual energy costs), WINDOW (for calculating a products thermal performance properties), THERM (a preprocessor for WINDOW that determines two-dimensional heat-transfer effects), and Optics (a preprocessor for WINDOWs glass database).
Software not only offers a less expensive means than testing to evaluate window performance, it can also be used during the design process to help manufacturers produce windows that will meet target specifications. In addition, software can show small improvements in window performance that might not be detected in actual testing because of large uncertainties in test procedures.
1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aHuang, Yu, Joe1 aHuizenga, Charlie1 aMitchell, Robin1 aRubin, Michael, D. uhttps://facades.lbl.gov/publications/state-art-software-window-energy01900nas a2200181 4500008004100000050001500041245014300056210006900199260002500268490001600293520122000309100002201529700002501551700002901576700002001605700002401625856006901649 1998 eng d aLBNL-4210200aTeaching Students about Two-Dimensional Heat Transfer Effects in Buildings, Building Components, Equipment, and Appliances Using THERM 2.00 aTeaching Students about TwoDimensional Heat Transfer Effects in aChicago, ILc01/19990 v105, Part 13 aTHERM 2.0 is a state-of-the-art software program, available for free, that uses the finite-element method to model steady-state, two-dimensional heat-transfer effects. It is being used internationally in graduate and undergraduate laboratories and classes as an interactive educational tool to help students gain a better understanding of heat transfer. THERM offers students a powerful simulation engine combined with a simple, interactive interface and graphic results. Although it was developed to model thermal properties of building components such as windows, walls, doors, roofs, and foundations, it is useful for modeling thermal bridges in many other contexts, such as the design of equipment. These capabilities make THERM a useful teaching tool in classes on: heating, ventilation, and air-conditioning (HVAC); energy conservation; building design; and other subjects where heat-transfer theory and applications are important. THERMs state-of-the-art interface and graphic presentation allow students to see heat-transfer paths and to learn how changes in materials affect heat transfer. THERM is an excellent tool for helping students understand the practical application of heat-transfer theory.
1 aHuizenga, Charlie1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aMitchell, Robin1 aGriffith, Brent, T. uhttps://facades.lbl.gov/publications/teaching-students-about-two01730nas a2200157 4500008004100000050002100041245009800062210006900160520114800229100002901377700002001406700002501426700002201451700002401473856007501497 1998 eng d aLBL-37371 Rev. 200aTHERM 2.0: a PC Program for Analyzing Two-Dimensional Heat Transfer through Building products0 aTHERM 20 a PC Program for Analyzing TwoDimensional Heat Transfer3 aTHERM is a state-of-the-art, Microsoft Windows?-based computer program developed at Lawrence Berkeley National Laboratory (LBNL) for use by building component manufacturers, engineers, educators, students, architects, and others interested in heat transfer. Using THERM, you can model two-dimensional heat-transfer effects in building components such as windows, walls, foundations, roofs, and doors; appliances; and other products where thermal bridges are of concern. THERM's heat-transfer analysis allows you to evaluate a product?s energy efficiency and local temperature patterns, which may relate directly to problems with condensation, moisture damage, and structural integrity.
This version of THERM includes several new technical and user interface features; the most significant is a radiation view-factor algorithm. This feature increases the accuracy of calculations in situations where you are analyzing non-planar surfaces that have different temperatures and exchange energy through radiation heat transfer. This heat-transfer mechanism is important in greenhouse windows, hollow cavities, and some aluminum frames.
1 aFinlayson, Elizabeth, U.1 aMitchell, Robin1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aCurcija, Dragan, C. uhttps://facades.lbl.gov/publications/therm-20-pc-program-analyzing-two01722nas a2200169 4500008004100000245006100041210006100102260003100163490001600194520115400210100002501364700002901389700002401418700001601442700002201458856007201480 1997 eng d00aGuidelines for Modeling Projecting Fenestration Products0 aGuidelines for Modeling Projecting Fenestration Products aSan Francisco, CAc01/19980 v104, Part 13 aHeat transfer patterns in projecting fenestration products (greenhouse windows, skylights, etc.) are different than those with typical planar window products. The projecting surfaces often radiate to each other, thereby invalidating the commonly used assumption that fenestration product interior surfaces radiate to a uniform room air temperature. The convective portion of the surface heat transfer coefficient is also significantly different from the one used with planar geometries, and is even more dependent on geometry and location. Projecting fenestration product profiles must therefore be modeled in their entirety. This paper presents the results of complete cross section, variable film-coefficient, 2-D heat transfer modeling of two greenhouse windows using the next generation of window specific heat transfer modeling tools. The use of variable film-coefficient models is shown to increase the accuracy with which simulation tools can compute U-factors. Simulated U-factors are also determined using conventional constant film coefficient algorithms. The results from both sets of simulations are compared with measured values.
1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aCurcija, Dragan, C.1 aBaker, Jeff1 aHuizenga, Charlie uhttps://facades.lbl.gov/publications/guidelines-modeling-projecting03749nas a2200193 4500008004100000245010100041210006900142260003400211520306200245100002903307700002503336700002303361700001803384700002103402700002203423700002403445700001603469856007003485 1995 eng d00aAdvances in Thermal and Optical Simulations of Fenestration Systems: The Development of WINDOW 50 aAdvances in Thermal and Optical Simulations of Fenestration Syst aClearwater Beach, FLc12/19953 aWINDOW is a personal-computer-based computer program used by manufacturers, researchers, and consumers to evaluate the thermal performance properties (U-factors, solar heat gain and shading coefficients, and visible transmittances) of complete windows and other fenestration systems. While WINDOW is used by thousands of users in the United States and internationally and is at the foundation of the National Fenestration Rating Council's U-factor and solar heat gain property procedures, improvements to the program are still necessary for it to meet user needs. Version 5, intended for release in late 1995, is being developed to meet these needs for increased accuracy, a flexible and state-of-the-art user interface, and the capabilities to handle more product types.
WINDOW 5 includes the capabilities to define and model the thermal performance of frames/dividers and their associated edge effects. Currently, such an analysis must be performed outside of WINDOW and requires simplifications to be made to frame profiles or is based on the use of generic frame and edge correlations. WINDOW's two-dimensional thermal model is composed of four sections: a graphical input, automatic grid generation, an finite-element analysis (FEA) solution, and the display of results. In the graphical input section, users are able to directly import a computer-aided design (CAD) drawing or a scanned image of a window profile, replicate its exact geometry, and assign material types and boundary conditions. The automatic grid generation is transparent to the user, with the exception of the requirement that complex shapes (i.e., an aluminum extrusion) be broken down into simpler polyshapes. Inclusion of an automatic grid generation makes detailed "true geometry" frame-and-edge heat-transfer analysis accessible to users without extensive knowledge of numerical methods of heat-transfer analysis. After the cross section is meshed it is sent to the FEA engine for solution and the results are returned. A postprocessor allows for the visual display of temperature and heat flux plots. Note that while this two-dimensional heat-transfer tool is being developed specifically for fenestration products, it also can be used to analyze other building envelope components.
WINDOW 5 also will include a built-in version of a national laboratory's program that allows the user to estimate the orientation-dependent annual energy impacts of a given window in a typical residence in various U.S. climates. This program is based on regressions to a database of DOE2.1 runs. Future versions will include a similar feature for commercial buildings.
Other technical additions include an improved angular/ spectral model for coated and uncoated glazings, the ability to analyze the optical properties of nonhomogeneous layers, and the ability to model the effects of laminated glazing layers. A door module permits the user to compute the total U-factors of exterior doors based on component U-factors calculated using the two-dimensional FEA module.
1 aFinlayson, Elizabeth, U.1 aArasteh, Dariush, K.1 aRubin, Michael, D.1 aSadlier, John1 aSullivan, Robert1 aHuizenga, Charlie1 aCurcija, Dragan, C.1 aBeall, Mark uhttps://facades.lbl.gov/publications/advances-thermal-and-optical01540nas a2200133 4500008004100000050001400041245003600055210003400091520113400125100002501259700002901284700002201313856007101335 1994 eng d aLBL-3529800aWINDOW 4.1: Program Description0 aWINDOW 41 Program Description3 aWINDOW 4.1 is a publicly available IBM PC compatible computer program developed by the Windows and Daylighting Group at Lawrence Berkeley Laboratory for calculating total window thermal performance indices (i.e. U-values, solar heat gain coefficients, shading coefficients, and visible transmittances). WINDOW 4.1 provides a versatile heat transfer analysis method consistent with the rating procedure developed by the National Fenestration Rating Council (NFRC). The program can be used to design and develop new products, to rate and compare performance characteristics of all types of window products, to assist educators in teaching heat transfer through windows, and to help public officials in developing building energy codes.
WINDOW 4.1 is an update to WINDOW 4.0. The WINDOW 4 series is a major revision to previous versions of WINDOW. We strongly urge all users to read this manual before using the program. Users who need professional assistance with the WINDOW 4.1 program or other window performance simulation issues are encouraged to contact one or more of the NFRC-accredited Simulation Laboratories.
1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aHuizenga, Charlie uhttps://facades.lbl.gov/publications/window-41-program-description01036nas a2200157 4500008004100000050001400041245005600055210005400111520051900165100002900684700002500713700002200738700002300760700001800783856007700801 1993 eng d aLBL-3394300aWindow 4.0: Documentation of Calculation Procedures0 aWindow 40 Documentation of Calculation Procedures3 aWINDOW 4.0 is a publicly available IBM PC compatible computer program developed by the Building Technologies Group at the Lawrence Berkeley Laboratory for calculating the thermal and optical properties necessary for heat transfer analyses of fenestration products. This report explains the calculation methods used in WINDOW 4.0 and is meant as a tool for those interested in understanding the procedures contained in WINDOW 4.0. All the calculations are discussed in the International System of units (SI).
1 aFinlayson, Elizabeth, U.1 aArasteh, Dariush, K.1 aHuizenga, Charlie1 aRubin, Michael, D.1 aReilly, Susan uhttps://facades.lbl.gov/publications/window-40-documentation-calculation