Novel method for measuring induction rates

This paper introduces a new technique for measuring induction ratios for different nozzle and combined flow geometries. The measurement technique only requires a single point velocity measurement in the secondary air inflow and a static pressure measurement in the primary air chamber. The design if the device allows the induction ratio to be determined for different primary air nozzle arrangements with different geometries for combined air discharge outlets. Experimentally measured data is compared with theoretical values. Four different sized circular nozzles with different outlet geometries were used to supply primary air into the device. The outlet geometries consisted of circular, slot and a rectangular shape. The results showed that the outlet geometry has very little or no effect on the induction ratio. The most important parameter in the induction ratio is the area ratio of the nozzle and the outlet.