Characterizing airflow through fabric air dispersion system using a porous media model

No existing diffuser models may be used to effectively describe the fabir air dispersion system (FADS), a new ventilation terminal made of ploymer. A porous media model was proposed to describe FADS in present work. And the corresonpongding mathematical model was developed for the airflow through FADS. The characteristics of airflow through FADS was predicted using the commercial software FLUENT with the standard k − ɛ turbulent model. The simulation results were well matched with the corresponding experimental value suggesting that it is feasible to describe FADS using the porous media model. Results showed that the air in the central zone flows forward with a decreasing velocity along the flow direction, and the air in the porous fibre eventually creeps out through its tiny-size holes at very low speed in the direction perpendicular to the porous fibre. The airflow close to the FADS is evenly distributed along the flow direction with a very low velocity. It is also concluded that the internal total pressure and dynamic pressure decrease slightly, while the internal static pressure increases slightly with a decaying increment along the flow direction of the FADS.