Air distribution in room ventilated by fabric air dispersion system

Abstract Several researches about airflow distribution in a room generated by fabric air dispersion system (FADS) were reported, but details about the simulation in computer fluid dynamics (CFD) method were not elaborated. In present work The commercial software FLUENT with standard k − e turbulence model is applied to predict air distribution in a room ventilated by FADS in penetration mode, where FADS is described with the porous media model based on the modified Forchheimer equation. And more details about the simulation are given. Flow visualization near the region of FADS is conducted using dry-ice as a smoking material. The distribution of indoor air velocity and temperature and draught rating (DR) around the ankle and neck level are predicted. The simulation well matches the corresponding experimental value and results of earlier work. Results showed that air is radially discharged out in the direction perpendicular to the spatial cambered porous fibre in lower velocity, and evenly distributed along its length direction when air is distributed by FADS in penetration mode. The velocity of indoor air is very low, and the vertical air temperature difference is small (less than 2 K). DR around the ankle and neck is immune to supply air flow rate and location, which is less than the comfort limit of ASHRAE Standard 55-2004. In addition, airflow pattern is greatly impacted by the location and strength of heat load.

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