what is radial flow?

Question

fluid radial flow

Answer 1

Radial flow can be best understood with the example with radial flow pump.
In a radial flow pump, the liquid enters at the centre of the impeller and is directed out along the impeller blades in a direction at right angles to the pump shaft.
For diagram pl. click:
http://www.engineersedge.com/pumps/radial_flow.htm
http://www.spxprocessequipment.com/sites/lightnin/radial_flow_imps.asp

Answer 2

Picture a rotating member (like a rotor for an electric machine).

Radial flow moves from the shaft (center of the rotating member) toward the exterior surface. This is a common method for cooling AC machines, for example. - It also describes how air moves through the stationary portion to cool the windings embedded there.

Axial flow moves parallel to the shaft - either from one end to the other, or from both ends toward the midpoint. In the first case, there may be radial flow through the rotating section (as air is forced outward from the shaft by centrifugal force), but the passage of air through the stationary portion remains primarily axial. In the second case, there is probably some radial flow occurring as air exits from the spinning rotor at the machine midpoint, and there will definitely be some radial flow to allow air to exhaust through the stationary portion at the midpoint. However, cooling through the ends of the machine (i.e. before the midpoint is reached) should be primarily axial.