THE EFFECTS OF INFRARED ABSORBING GASSES ON WINDOW HEAT-TRANSFER - A COMPARISON OF THEORY AND EXPERIMENT

This paper extends an existing heat transfer model of multipane windows filled with gasses to include the effects of infrared absorption within the gasses. A one-dimensional, finite-element, control-volume approach for calculating the heat transfer across a horizontal window filled with an infrared absorbing gas is presented. This model includes the coupled effects of conduction and radiation but not convection. Experimental data on the heat transfer rates through windows filled with infrared absorbing gasses and heated from above (to minimize convection) agree with results from this model. Infrared absorbing gasses are shown to have a small effect on reducing heat transfer through common window systems and are not as effective as low-emittance coatings for reducing radiative heat transfer. © 1990.