Dynamic insulation applied to the residential building (Part 2). Numerical Evaluation of Thermal Insulation Effect on Air Supply Window System

We designed a new air supply window system to ventilate indoors through the air space of a double pane window and evaluated its insulation efficiency and probability of moisture condensation in order to confirm its feasibility and applicability. Then, to verify its thermal insulation efficiency, we evaluated its temperature contribution with different air space widths using computational fluid dynamics. In addition, to verify the probability of moisture condensation, we calculated the surface temperature of the windowpane with different outdoor temperatures based on fixed indoor conditions such as air temperature and humidity ratio. The calculated results show that the heat loss/gain in the room was reduced with increasing air space width of a double pane window. Moisture condensation on the surface of an indoor windowpane depends on the outdoor temperature and it occurred when the outdoor temperature was 0 ºC in all calculated cases of the proposed system. Moreover, low-temperature outdoor air comes into the indoors through the air space of the double pane window, the relationship of the temperature difference between the indoor air/outdoor air and supply air/outdoor air was calculated as a linear approximation.