| Abstract: | SUMMARIES. An Excel spreadsheet ( WINVENT) that calculates the temperature distribution across the center of a double-glazed window is described. The spreadsheet was used to model a typical protective glazing installation for a stained glass window under both unvented and vented conditions where a vertical channel is created along the entire length of the glazing system. Analysis of the data generated by the spreadsheet is used to discuss the merits of protective glazing.
CONCLUSION. WINVENT is an Excel spreadsheet that calculates the temperature distribution across the center of a stained glass window when protective glazing is installed external to the stained glass surface. The spreadsheet incorporates a number of different con¬vection correlations for the space between the glaz¬ing layers in order to simulate unvented and vented air spaces. The spreadsheet also compares the dew-point temperature of the air space with the coldest temperature of the surfaces facing the gap and determines whether or not condensation will occur. The program allows the user to select the interior and exterior convection correlations and change sky conditions between clear and cloudy as well as input different glass types, gap widths and glazing heights. WINVENT can be used to model a typical pro¬tective glazing installation for a stained glass win¬dow under both unvented and vented conditions where a vertical channel is created along the entire length of the glazing system without obstruction. Under vented conditions, the channel is open to the exterior along its entire length at the top and bottom. Given these conditions, WINVENT may be used to predict the microclimate of the air space created by the installation of the protective glazing in a hot and humid climate. These data can be used to assess the long-term impact of protective glazing on stained glass windows and associated structural supports. Copies of WINVENT may be obtained upon request from the first-named author. The applica¬tion of WINVENT is relatively straightforward and is designed for ease of use by stained glass conser¬vators. |
|---|
