A new low-temperature hermetic composite edge seal for the fabrication of triple vacuum glazing

Abstract

Please cite this article as: Memon S, Farukh F, Eames PC, Silberschmidt VV, A new low-temperature hermetic composite edge seal for the fabrication of triple vacuum glazing, Vaccum (2015Vaccum ( ), doi: 10.1016Vaccum ( / j.vacuum.2015 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 2 AbstractHigh performance low-cost vacuum glazing is a key development in the move to more energy-efficient buildings. This study reports the results of experimental and theoretical investigations into the development of a new low-temperature (less than 200˚C) composite edge seal. A prototype triple vacuum glazing of dimensions 300mmx300mm was fabricated with a measured vacuum pressure of 4.8x10 -2 Pa achieved. A three-dimensional finite-element model for this prototype triple vacuum glazing with the composite edge seal was also developed. Centre-of-pane and total thermal transmittance values for this small prototype of the triple vacuum glazing were predicted to be 0.33 Wm -2 K -1 and 1.05 Wm -2 K -1 , respectively. It was predicted using the developed model that the thermal performance could be improved by reducing the width of the composite edge seal and by the use of soft low-emissivity coatings on the glass surfaces. Detailed three-dimensional isothermal contour plots of the modelled triple vacuum glazing are presented.

Solar Energy Gain and Space-Heating Energy Supply Analyses for Solid-Wall Dwelling Retrofitted with the Experimentally Achievable U-value of Novel Triple Vacuum Glazing

“…It can be seen that an increase in the frame percentage of the total window area decreases the value of Uw for single, double air glazed and double argon glazed windows. It is because of the frame thermal transmittance (Uf value) is smaller than that of [21] centre-of-pane thermal transmittance (Ug value). Increasing the frame percentage area of the total window, in the case of triple air glazing, the Uw values calculated were nearly the same to the frame Uf value (i.e.…”

“…To reduce the heat loss to a level where the U-value is less than 0.5 Wm -2 K -1 , the concept of triple vacuum glazing was introduced [18] and the best predicted U-value of 0.26 Wm -2 K -1 was reported [19]. In this paper the achievable U-value of a new fabricated sample of composite edge sealed triple vacuum glazing [20][21][22] 0.33 Wm -2 K -1 is used to predict and analyse the implications on heating energy savings, solar energy gains and heat loss in the UK solidwall dwelling in comparison to a range of conventional window types, i.e. single glazed, double air glazed, double argon glazed, triple air glazed windows.…”

“…A composite edge sealed triple vacuum glazing consists of three sheets of tin-oxide (SnO2) coated k-glass, an airtight seal around the edge of the three glass sheets, and two evacuated cavities at a pressure below 0.1 Pa to decrease heat transfer by gaseous conduction and convection to a negligible level. Radiative heat transfer can further be minimised to a low level by using soft low-emittance coatings, such as silver (Ag) on the surfaces of the glass sheets [16,21]. An ordered arrangement of stainless steel support pillars, typically 0.15 mm high and 0.3mm diameter, maintain the separation of the three glass sheets [19].…”

“…An ordered arrangement of stainless steel support pillars, typically 0.15 mm high and 0.3mm diameter, maintain the separation of the three glass sheets [19]. Details of the fabrication and predicted thermal performance are reported elsewhere [21] while the sample design is illustrated in Fig. 1. …”

Design, Development and Thermal Performance Analysis of Ultra-Low Heat Loss Triple Vacuum Glazing

“…In this paper, the design, development, fabrication methods and U-value predictions of a new dual-edge sealed triple vacuum glazing are reported. A dual-edge seal is hermetic and it consists of Cerasolzer alloy CS186 as a main seal and J-B weld epoxy steel resin as a support seal (Memon et al, 2015). A triple vacuum glazing consists of three SnO2 coated k-glass sheets, air-tight sealed around the edges, with evacuated two narrow (0.15mm high) cavities having a pressure of 0.01 Pa. A regular square array of stainless steel support pillars, typically 0.15mm high and 0.3mm diameter spaced at 24mm, maintains the separation of three glass sheets under the effects of atmospheric and vacuum pressure.…”