Application of flow distribution method of equivalent circulation area to calculation of pressurized air supply

The flow pattern of parallel and series airstream is described as follows: regardless of the number of openings and gaps passing by series airstream, the resistance can be represented by the equivalent circulation area; the pressure drop of parallel airstreams is equal, the flow ratio of paths is proportional to the ratio of equivalent circulation area, i.e. the total flow into the positive pressure space is distributed by the equivalent circulation area of parallel airstreams. Therefore if the flow rate of any path in parallel airstream is known, the flow of other paths(including the total flow) in a smoke control system can be calculated. According to the technical provisions of smoke control system, the velocity of the airstream passing the fire door which between the hallway and its antechamber (or common antechamber)must not less than 0.7 to 1.2 m/s to resist invasion of the smoke, the open area of the fire door is determined according to the design value, so smoke flow of the parallel airstream can be calculated. Then, the mathematical model of Sub-items can be developed, providing new approaches for optimization of smoke control scheme.