Full scale experimental study of single-sided ventilation: Analysis of stack and wind effects

Natural ventilation can contribute to the reduction of the air conditioning demand and to the improvement of thermal comfort in buildings. In this paper, the flow field and the air change rate generated by a simple configuration of natural ventilation, namely single-sided ventilation, are examined experimentally. The experiments are realized in a full scale building exposed to outdoor conditions, using several measurement techniques. The main features of the flow generated by stack and wind effect are examined for different outdoor conditions (temperature difference, wind speed and direction). Finally, measured air change rates are compared to those calculated by existing correlations in order to analyze their applicability to the experimental configuration. Results show that the wind generates turbulence diffusion at the opening, counteracting the stack effect. Moreover, in the case of windward opening, there is an additional effect, namely the effect of mixing layer, which tends to increase the airflow rate. Existing correlations give reasonably good results in the case of windward opening, while in the case of leeward opening they overestimate the airflow rate.

► We analyze experimentally the combination of wind and stack effects.
► Wind generates turbulence diffusion at the opening, counteracting the stack effect.
► Only for a windward opening, wind generates a mixing layer, increasing airflow rate.
► Existing correlations give good estimation of airflow rate for a windward opening.
► Existing correlations overestimate the airflow rate for a leeward opening.