Simulation study on an air flow window system with an integrated roll screen

Abstract

A numerical calculation procedure for an air flow window (AFW) system integrated with a roll screen is presented. Both heat and air flows within the window elements such as the outside pane of glass, the outside air space, a venetian blind, the inside air space and a roll screen, are taken into account by considering the thermal and air flow networks. Agreements between measured and calculated results of temperatures and pressure differences through a series of experiments carried out in an environmental test chamber were observed. To identify the quantitative characteristics of an AFW integrated with a roll screen, a series of numerical simulations were performed with the results from using a large resistance to the air flow from the upper half area of the roll screen. These show that this was effective in terms of thermal characteristics and suggest that a tightly-meshed roll screen, situtated in the upper half area, is suitable for both environmental and design reasons. If the heated air flow generated from the inside air space to the room were dispersed properly, the thermal efficiency of the AFW integrated with a roll screen would be equal to a conventional AFW system. The effect of a cold draft passing though the roll screen is also discussed.