A Critical Review of Stall Control Techniques in Industrial Fans

Figure 6

Data recorded from a pair of circumferentially offset high frequency response pressure transducers located over the blades of a 1250 mm diameter model of a variable pitch in motion induced draft fan. Blade angle reduces with increasing time, with the fan finally transitioning from stalled operation to stable operation at 89 seconds, at which time blade angle had reduced from an initial 70° at 79 seconds to 50° at 89 seconds [36].