Numerical Study Of The Effect Of Air Terminal Layouts On The Performance Of Stratum Ventilation System

It has been found that air terminal layouts could affect ventilation performance in a room. As a new ventilation system, stratum ventilation was proposed to accommodate the elevated room temperature. Its performance with various air terminal layouts was investigated by numerical method in this research. Totally four different exhausts locations were studied to determine the optimal exhaust locations. Exhausts were located at (a) low level of the same wall of the supplies; (b) middle level of the wall opposite to the supplies; (c) low level of the wall opposite to the supplies and (d) ceiling level, respectively. Ventilation performances were evaluated by airflow pattern, temperature distribution, percentage of dissatisfied people due to draft (PD), air diffusion performance index (ADPI) and local mean age of air. The computational results were validated by experimental results. Simulated results indicated that performance with exhausts located at ceiling level was the worst. Therefore it is not suggested for stratum ventilation. For the other three layouts, similar airflow pattern and temperature distribution was observed with exhausts located at middle and low level of the wall opposite to supplies. Indoor environment could achieve thermal comfort and good air quality with exhausts located at low level of the same wall of the supplies. This arrangement also helps to save the space for system installation. It is therefore a better choice for stratum ventilation design if performance requirements are met