Summer study on thermal performance of an exhausting airflow window in evaporatively-cooled buildings

Abstract

By using exhaust mode ventilated windows in buildings cooled by evaporative cooler, the air flow channel of the window can play the role of natural relief air path. Thereby, the cooling potential of the relief air can be recovered and used to improve the thermal performance of the ventilated window. This paper investigates the thermal performance of an exhausting ventilated window in a typical evaporatively-cooled space. In this study, a zonal model has been used for simulation. The numerical approach was validated with reported experimental data and good agreement was shown. Results showed that the heat gain and the maximum daily temperature of the interior glass pane of the proposed ventilated window are less than those of the conventional double-glazed window. Providing natural relief through ventilated window can cause extra pressure drop and consequently reducing cooling capacity. This may also disturb the occupant's comfort due to noise issue. Hence, the impacts of window aspect ratio and thickness of the air flow channel have been investigated as effective factors on pressure drop and sound power level. Eventually, a step by step procedure has been proposed for determining the geometric parameters of the ventilated window for practical use in evaporatively-cooled buildings.