The Effect of Glass Thickness on Stress in Vacuum Glazing
Authors: Farid Arya, Trevor Hyde, Andrea Trevisi, Paolo Basso, Danilo Bardaro
Heat transfer through multiple pane windows can be reduced by creating a vacuum pressure less than 0.1 Pa between the glass panes, with low emittance coatings on one or more of the internal surfaces. Fabrication of vacuum glazing (VG) requires the formation of a hermetic seal around the periphery of the glass panes together with an array of support pillars between the panes to prevent them from touching under atmospheric pressure. Atmospheric pressure and temperature differentials induce stress which can affect the integrity of the glazing. Several parameters define the stresses in VG including the glass thickness, pillar specifications, glazing dimensions and edge seal configuration. Inherent stresses in VG can result in fractures in the glass panes and failure of the edge seal. In this study, stress in VG with different glass thicknesses is theoretically studied using Finite Element Modelling (FEM). Based on the finding in this study, suggestions are made to address problems resulting from the use of thinner glass panes in the fabrication of VG. This can lead to the development of high performance, light and thin VG.
Keywords: stress, glazing, ABAQUS, vacuum glazing, vacuum insulation
[1]	A. Zoller, "Hohle Glasscheibe," German Patent Application, 1913, 387655.
[2]	R. E. Collins, A. C. Fischer-Cripps, "Design of support pillar arrays in flat evacuated windows," Australian Journal of Physics, 1991, 44, pp. 73-86.
[3]	R. E. Collins, G. M. Turner, A. C. Fischer-Cripps, J. Z. Tang, T. M., Simko, C. J. Dey, D. A. Clugston, Q. C. Zhang, J. D. Garrison, "Vacuum glazing - A new component for insulating windows," Building and Environment,1995, 30(4), pp. 459-492.
[4]	A. C. Fischer-Cripps, R. E. Collins, G. M. Turner, E. Bezzel, "Stresses and Fracture Probability in Evacuated Glazing," Building and Enoironmenf, 1995, Vol. 30, No. I, pp. 41-5.
[5]	R. E. Collins, T. M. Simko, "Current status of the science and technology of vacuum glazing," Solar Energy, 1998, 62(3), pp. 189-213.
[6]	J. Wang, P.C. Eames, J.F. Zhao, T. Hyde, Y. Fang, "Stresses in vacuum glazing fabricated at low temperature," Solar Energy Materials & Solar Cells, 2007, 91, 290 - 303.
[7]	J. Zhao, S. Luo, X. Zhang, W. Xu, "Preparation of a transparent supporting spacer array for vacuum glazing," Vacuum, 2013, 93, 60-64.
[8]	E. Cuce, S. B. Riffat, "Aerogel-Assisted Support Pillars for Thermal Performance Enhancement of Vacuum Glazing: A CFD Research for a Commercial Product," 2015, Arab J Sci Eng 40:2233 - 2238.
[9]	R. E. Collins, S. J. Robinson, "Evacuated windows," Solar Energy, 1991, Vol. 47, No. 1, pp. 27-38.
[10]	R. E. Collins, A. C. Fischer-Cripps, J. Z. Tang, "Transparent evacuated insulation," Solar Energy, 1992, 49(5), pp. 333-350.
[11]	T. M. Simko, A. C. Fischer-Cripps, R. E. Collins, "Temperature-induced stresses in vacuum glazing: Modeling and experimental validation," Solar Energy, 1998, 63(1), pp. 1-21.
[12]	A. C. Fischer-Cripps, R. E. Collins, G. M Turner, E. Bezzel, "Stresses and fracture probability in evacuated glazing," Building and Environment, 1995, 30(1), pp. 41-59.
[13]	A. C. Fischer-Cripps, R. E. Collins, "Architectural glazings: Design standards and failure models" Building and Environment, 1995, 30(1), pp.29-40.
[14]	Y. Fang, P. C. Eames, B. Norton, "Effect of glass thickness on the thermal performance of evacuated glazing," Solar Energy, 2007, 81(3), pp. 395-404.
[15]	F. Arya, T. Hyde, "Theoretical Study of Flexible Edge Seals for Vacuum Glazing," World Academy of Science, Engineering and Technology International Journal of Structural and Construction Engineering, 2017, Vol:11, No:8, 2017.
[16]	P. Henshall, P. Eames, F. Arya, T. Hyde, R. Moss, S. Shire, "Constant Temperature Induced Stresses in Evacuated Enclosures for High Performance Flat Plate Solar Thermal Collectors," Solar Energy, 2016, Volume 127, 250–261.
[17]	Y. Fang, T. Hyde, F. Arya, N. Hewitt, P.C. Eames, B. Norton, S. Miller, "Indium alloy-sealed vacuum glazing development and context," Renewable and Sustainable Energy Reviews, 2014, 37, 480-501.
[18]	Y. Fang, T. Hyde, F. Arya, N. Hewitt, R. Wang, Y. Dai, "Enhancing the thermal performance of triple vacuum glazing with low emittance Coatings" Energy and Buildings, 2015, 97, 186–195.
[19]	Y. Fang, T. Hyde, F. Arya, N. Hewitt, "A novel building component hybrid vacuum glazing-a modeling and experimental validation," ASHRAE, 2013, Volume 119, Part 2.