Impacts of wind on solar chimney performance in a building

The interaction between solar chimney and wind were investigated numerically and theoretically. A higher wind velocity does not represent a better performance, which depends on wind angle (α), which is the angle between wind direction and outward normal of the wall with the window. A windward situation (0°≤α < 90°) is suggested, where the scenario with α = 0 shows the best performance. It is surprising that the leeward scenario with α = 180° presents a slightly positive effect, but scenarios with 90°≤α < 180° show negative effects. Window area (Aw) presents a positive effect on the airflow rate, which shows a linear relationship with Aw0.34 and Aw0.46 when the α is 0° and 45°, respectively. A theoretical model was developed to predict the airflow rate under α < 90°, where for 90°≤α < 180° the related predictions can be based on the scenario without wind. The predictions are fitting quite well with numerical results. Critical wind velocity was also proposed to represent the wind velocity which overrules the performance that solar chimney is no longer dependent on solar radiation but wind. The critical wind velocity keeps increasing under higher solar radiation, where for the analysed model it increases from 0.65 to 1.55 m/s when solar radiation rises from 100 to 1300 W/m2.