The compressor of the turbofan engine shown above is axial: the air moves primarily in a direction parallel to the axis of the engine. Each stage of the axial compressor consists of a rotor and a stator. Both rotor and stator are made up of a large number of individual blades, which are twisted airfoils, usually with a high degree of camber. The rotor blades add work to the air, so that the stagnation enthalpy rises, along with the stagnation temperature and stagnation pressure. This is usually accompanied by an increase in the velocity. The stator blade passages straighten out the flow and act as diffusers, slowing down the flow and thus increasing the static pressure and static temperature.
flow through an axial compressor can be considered to consist of three types of
1. Axisymmetric flow with work addition through an annular duct:
2. Flow over blade rows (cascades)
3. Secondary flows (recirculating flows, tip vortices, hub vortices, rotor/stator interactions, etc.)