Patent ID: 8185349

Claim:
A method of preventing an incipient stall of a fluid flow in an axial flow device comprising: mounting a plasma probe to an inner surface of a housing of the axial device, the housing of the axial flow device having an inner surface, an outer surface, a fluid inlet, a fluid outlet, and a plurality of blades rotatable within the housing; rotating the plurality of blades within the housing to create the fluid flow between the fluid inlet and the fluid outlet; generating a voltage to form a plasma, the plasma being exposed to the fluid flow; detecting periodically at least one characteristics of the generated plasma; measuring the characteristic of the generated plasma as the plasma is disturbed by the fluid flow; identifying a variation in the measured characteristic of the generated plasma to predict the incipient stall of the fluid flow; comparing the measured characteristic to a threshold to identify the variation; and modifying the rotation of the plurality of blades to prevent the incipient stall of the fluid flow.