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Thermal performance and condensation risk of single-pane glazing with low emissivity coatings

Published online by Cambridge University Press:  11 March 2020

Qiuhua Duan
Affiliation:
Architectural Engineering Department, Pennsylvania State University, State College, USA
Yuan Zhao
Affiliation:
Architectural Engineering Department, Pennsylvania State University, State College, USA
Julian Wang*
Affiliation:
Architectural Engineering Department, Pennsylvania State University, State College, USA
*
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Abstract

To understand the potential impacts on both thermal performance and condensation risks of using low-e coatings in buildings, especially in the single-pane sector, in this work, parametric numerical analysis in winter is conducted. Three building glazing models, including the single-pane without low-e coatings (SNL), single-pane with exterior low-e coatings (SEL), and single-pane with interior low-e coatings (SIL), are selected and simulated through COMSOL over a range of outdoor temperature and indoor humidity. The temperature of the interior surface of windows, heat flux through windows, winter U-factor of center-of-glass will be obtained and compared. Additionally, a numerical code is developed in R to compute and plot the condensation temperatures of these three models upon the given indoor humidity levels and simulated surface temperatures. The comprehensive analysis of condensation risks on the glazing inner surface of the three models will be conducted.

This parametric simulation effort indicates an interesting feature for a single-pane window: while the SIL gives a substantially lower U than the SNL, it also corresponds to an increased condensation risk under certain limits of external temperature and indoor humidity levels. Upon the resultant condensation temperatures and thermal performance analysis, we can conclude the parameters of the windowpane property, coating emissivity and placement, local climate, and building interior thermal settings must be taken into account collectively when it comes to adding low-e coatings to single-pane windows.

Type
Articles
Copyright
Copyright © Materials Research Society 2020

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References

Goetzler, W., Guernsey, M., and Young, J., “Research & Development Roadmap for Emerging HVAC Technologies,” Washington, DC., 2014.Google Scholar
Carmody, J., Selkovitz, S., Lee, E. S., Arasteh, D., and Willmert, T., Window Systems for High-Performance Buildings, 1st ed. New York, London: American Society of Civil Engineers, 2004.Google Scholar
U. S. DoE, “Buildings energy data book,” Energy Efficiency & Renewable Energy Department, 2011.Google Scholar
Apte, J. and Arasteh, D., “Window-related energy consumption in the US residential and commercial building stock,” Buildings, pp. 138, 2006.Google Scholar
Herron, T., “Low-E Glass information,” Thermal WIndows, Inc. [Online]. Available: https://www.thermalwindows.com/products/lowe/.Google Scholar
IAQ, I. A. Q., “Moisture Control Guidance for Building Design, Construction and Maintenance,” EPA 402-F-13053, 2013.Google Scholar
Efficient Windows Collaborative, “Window Technologies: Low-E Coatings.” [Online]. Available: https://www.efficientwindows.org/lowe.php.Google Scholar
Glass Rite, “What are low-e windows, and why buy them?,” 2012. [Online]. Available: https://www.glass-rite.com/2012/03/14/what-are-low-e-windows-and-why-buy-them/.Google Scholar
N. F. R. C. Incorporated, NFRC 500-2017: Procedure for determining fenestration product condensation resistance values. ASTM International, 2013.Google Scholar
A. S. of H. R. and A.-C. E. ASHRAE, 2013 ASHRAE Handbook-Fundamentals. ASHRAE, 2013.Google Scholar
AAMA, A. A. M. A., “Condensation Resistance Factor Tool,” American Architectural Manufacturers Association. [Online]. Available: https://aamanet.org/pages/crf-tool.Google Scholar
Knox, J. R. and Widder, S. H., “Characterization of Energy Savings and Thermal Comfort Improvements Derived from Using Interior Storm Windows,” Pacific Northwest National Laboratory, 2013.CrossRefGoogle Scholar
Garber-Slaght, R. and Craven, C., “Evaluating window insulation for cold climates,” J. Green Build., vol. 7, no. 3, pp. 3248, 2012.CrossRefGoogle Scholar
Hwang, J. H., Lee, B. I., Klep, V., and Luzinov, I., “Transparent hydrophobic organic-inorganic nanocomposite films,” Mater. Res. Bull., vol. 43, no. 10, pp. 26522657, 2008.CrossRefGoogle Scholar
Nakajima, A., “Design of a transparent hydrophobic coating,” J. Ceram. Soc. Japan, vol. 112, no. 1310, pp. 533540, 2004.CrossRefGoogle Scholar
Wang, F. et al., “A simple method for preparation of transparent hydrophobic silica-based coatings on different substrates,” Appl. Phys. A Mater. Sci. Process., vol. 106, no. 1, pp. 229235, 2012.CrossRefGoogle Scholar
Kim, H. M., Sohn, S., and Ahn, J. S., “Transparent and super-hydrophobic properties of PTFE films coated on glass substrate using RF-magnetron sputtering and Cat-CVD methods,” Surf. Coatings Technol., vol. 228, no. SUPPL.1, 2013.CrossRefGoogle Scholar
Wang, J. and Shi, D., “Spectral selective and photothermal nano structured thin films for energy efficient windows,” Appl. Energy, no. 208, pp. 8396, 2017.Google Scholar
Zhao, Y. et al., “Photothermal effect on Fe3O4nanoparticles irradiated by white-light for energy-efficient window applications,” Sol. Energy Mater. Sol. Cells, 2017.CrossRefGoogle Scholar