"Axial Fan" performance curve impeller speed and blade mounting angle must be measured to, i.e. pressure p, efficiency η, power N and the flow rate Q of the curve, and its shape is characterized by: pQ curve at low flow region saddle shape appears in the large flow area is very steep drop at Q = 0, p is the maximum. However, due to differences in the physical properties of the fluid, such that in practice, such a performance curve of the fan and the pump are different. As this fan static pressure, static pressure efficiency curve, this dimensionless fan performance curve, all it has important applications in the fan.