Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1550974 | Solar Energy | 2010 | 8 Pages |
Abstract
The simulated triple vacuum glazing (TVG) consists of three 4Â mm thick glass panes with two vacuum gaps, with each internal glass surface coated with a low-emittance coating with an emittance of 0.03. The two vacuum gaps are sealed by an indium based sealant and separated by a stainless steel pillar array with a height of 0.12Â mm and a pillar diameter of 0.3Â mm spaced at 25Â mm. The thermal transmission at the centre-of-glazing area of the TVG was predicted to be 0.26Â WÂ mâ2Â Kâ1. The simulation results show that although the thermal conductivity of solder glass (1Â WÂ mâ1Â Kâ1) and indium (83.7Â WÂ mâ1Â Kâ1) are very different, the difference in thermal transmission of TVGs resulting from the use of an indium and a solder glass edge seal was 0.01Â WÂ mâ2Â Kâ1. This is because the edge seal is so thin (0.12Â mm), consequently there is a negligible temperature drop across it irrespective of the material that the seal is made from relative to the total temperature difference across the glazing. The results also show that there is a relatively large increase in the overall thermal conductance of glazings without a frame when the width of the indium edge seal is increased. Increasing the rebate depth in a solid wood frame decreased the heat transmission of the TVG. The overall heat transmission of the simulated 0.5Â m by 0.5Â m TVG was 32.6% greater than that of the 1Â m by 1Â m TVG, since heat conduction through the edge seal of the small glazing has a larger contribution to the total glazing heat transfer than that of the larger glazing system.
Related Topics
Physical Sciences and Engineering
Energy
Renewable Energy, Sustainability and the Environment
Authors
Yueping Fang, Trevor J. Hyde, Neil Hewitt,