Experimental investigation of thermal and ventilation performances of stratum ventilation

Abstract Stratum ventilation has been proposed to cope for elevated indoor temperatures. Air speed, temperature and CO 2 concentration of a stratum ventilated office are investigated experimentally. The data obtained under well defined conditions and therefore can be used for validating numerical models. Thermal comfort conditions and ventilation efficiency are studied based on the experimental results of four experimental cases. Thermal comfort indices, i.e. PMV, PPD and PD are calculated from measured data. The values of these indices are found to satisfy the requirements of ISO 7730, CR 1752-1998 and ASHRAE 55-2010. In terms of thermal comfort, the two cases with supply air temperature of 21 °C are found to perform better compared with the two cases with supply air temperature of 19 °C. For all the cases, the ventilation effectiveness is close to 1.5. This ventilation method could therefore be expected to provide indoor air quality in an efficient way.

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