Airflow characteristics generated by fabric air dispersion ventilation

Abstract

The air distribution characteristics of a fabric air dispersion system (FADS) were investigated experimentally in a full-scale chamber. The jet supply velocity and outlet orientation were selected as the major factors that affect the FADS airflow field. The FADS airflow structure was described and verified in a visualization experiment and compared with the air patterns of the traditional rectangular, circular nozzle and linear slot diffusers. The induction and flow junction phenomena were analysed under different combinations of outlet orientations. Experimental results showed that this induction phenomenon can create more airflow patterns and that the FADS can meet different requirements in practical engineering. The turbulence intensity of the air supply orifices, the maximum velocity decay, and the self-similarity of the velocity profiles were examined through velocity field measurements. Our research illustrated the advantages of two-dimensional flow characteristics of the FADS model that can be treated as a plane free jet in the developed region. The phenomenon we studied should provide useful guide for the application of the FADS to heating, ventilation, and air-conditioning systems.

Keywords

Ventilation Air distribution Fabric air dispersion system Full-scale experiment

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