VAV system analysis

There  are  two  kind  of  supply  fan  rotation  speed control methods, one is the static pressure control method, the other is the float pressure control method. Simulation shows that they have different working point along the whole year. The supply air fan controlled with float pressure control  method need low rotation speed and works on high efficiency, so the float pressure control method need only 30% fan operation energy of the static pressure control  method.  The  layout  of  the  air  duct  may influence the fan control method.