A computational method for calculating heat transfer and airflow through a dual-airflow window

An airflow window has great potential for conserving energy and improving indoor air quality in residential buildings. Existing airflow windows use a single airflow path, and their energy performance can be studied using several computational models. A dual-airflow window with triple glazing can conserve more energy than a singleairflow window, because the former works like a cross-counterflow heat exchanger. However, no suitable computer programs can be used to evaluate the energy performance of the dual airflow window. This paper proposes a four-step computational method that uses both computational fluid dynamics (CFD) and coded radiation calculations to determine airflow and heat transfer through the window. Experimental tests on a fullscale dual-airflow window system were used to obtain various indoor and outdoor air and window surface temperatures for validating the computer method. The agreement between the computed and measured temperatures is very good.