Abstract
Object of study:
Sucking nozzles which exhaust fly and dust in spinning mills usually expand at the throat. It is, therefore, necessary to get the proper expansion angle so that a nozzle may do uniform sucking on a plain covering a wide scope.
In a previous article (Part 1) we dealt theoretically with the characteristics of suction nozzles. In the present article we establish, by experiment, the reasonableness of our previous researches and make clear, empirically, the sucking characteristics of finned and pipy nozzles.
Main points of the present article:
1. The relation between the expansion angle of a nozzle and its sucking performance has been experimentally inquired into and experimental results obtained show that the best uniformity of sucking performance is obtainable from:
a) Slightly reduced rate of air flow
b) An expansion angle less than 60°
c) An expansion angle less than 30° at the throat of a circular nozzle.
2. The sucking characteristics of finned, finless and pipy nozzles have been clarified experimentally and date on designing them obtained.
