Renewable Energy, Vol.135, 450-464, 2019
The influence of low -temperature surface induction on evacuation, pump-out hole sealing and thermal performance of composite edge sealed vacuum insulated glazing
Hermeticity of vacuum edge-sealing materials are one of the paramount requirements, specifically, to the evolution of energy-efficient smart windows and solar thermal evacuated flat plate collectors. This study reports the design, construction and performance of high-vacuum glazing fabrication system and vacuum insulated glazing (VIG). Experimental and theoretical investigations for the development of vacuum edgeseal made of Sn-Pb-Zn-Sb-AITiSiCu composite in the proportion ratio of 56:39:3:1:1 by % (CS-186) are presented. Experimental investigations of the seven constructed VIG samples, each of size 300 mm 300 mm 4 mm, showed that increasing the hot-plate surface temperatures improved the cavity vacuum pressure whilst expediting the pump-out hole sealing process but also increases temperature induced stresses. Successful pump-out hole sealing process of VIG attained at the hot-plate set point temperature of 50 degrees C and the approximate cavity pressure of 0.042 Pa was achieved. An experimentally and theoretically validated finite volume model (FVM) was utilised. The centre-of-pane and total thermal transmittance values are calculated to be 0.91 Wm(-2)K(-1) and 1.05 Wm(-2)K(-1), respectively for the VIG. FVM results predicted that by reducing the width of vacuum edge seal and emissivity of coatings the thermal performance of the VIG is improved. (C) 2018 Elsevier Ltd. All rights reserved.