Heated industrial curtain

Abstract

A substantially transparent thermal barrier for use in an opening between a refrigerated area and an adjacent area having a significantly higher temperature is suspended by its upper margin from a header. The barrier is formed of a plurality of strips positioned adjacent to each other, each strip including at least two sheets of substantially transparent material fixed to each other so as to define a plurality of channels extending from the upper end to the lower end of each strip, with at least the upper ends of the channels being open. The header directs a flow of warmed and/or dried air into the upper end of the plurality of channels, the air preferably being taken from the colder of the two adjacent areas separated by the curtain. The air is warmed to a temperature about midway between the temperatures of the two areas separated by the curtain. As the air proceeds downward through the length of the channels, the air generally does not significantly change its temperature, and as a result, the warmed air flowing downward through the channels is delivered at the lower end of the strip at the same temperature as at the top of the strip. With the lower ends of the channels open, the air is delivered substantially at floor level immediately below the curtain and generally uniformly across the width of the opening in which the curtain is positioned. The air can be re-circulated by having closed bottom ends of the channels that communicate with return ducts leading back toward the header.