Research on Minimum Applicable Diameter of Slinger Used in Micro Turbojet

Aircraft engines have a strict limit on size, and the atomization performance of the slinger is better with the greater diameter. The minimum applicable diameter of the slinger is studied for that the atomization performance of the slinger is inadequate when the engine is starting-up, idle running or working at high altitude. The atomization performance of the slinger is the best when the fuel leaves the slinger in ligament formation, and the calculation method of the fuel flow range is obtained when the slinger is in ligament formation at different rotational speed. The spray SMD is calculated according to the fuel flow rate, and the calculation formula of the minimum applicable diameter which meets the engine starting-up and idle running requirements is deduced. The high altitude has a negative effect on the slinger atomization, and the calculation formula of the minimum applicable diameter at the altitude H is deduced. A certain engine rotational speed is 6000r/min when starting-up and 20000r/min when idle running. If the fuel is RP-3, the diameter of the slinger which used on ground should be greater than 7.77cm through theoretical analysis. When works at an altitude of 4000m, the slinger diameter should be greater than 9.49cm.