METHOD FOR IMPROVING CHARACTERISTICS OF DOUBLE-FLOW JET TURBINE ENGINE Russian patent published in 2012 - IPC F02K3/06 F02K1/46 

FIELD: engines and pumps.

SUBSTANCE: extreme values of cold flow expansion coefficient, which correspond to the beginning and the end of cruise flight phase, are determined. Reference value (VR) of expansion coefficient is chosen between the above extreme values. For that reference value (VR) of expansion coefficient there determined is theoretical value (Ath) of surface area of outlet hole (6) of cold flow as per additional theoretical value. Additional theoretical value represents the ratio between theoretical surface area of cold flow outlet hole and nominal cross-section area of the nozzle throat. Outlet hole (6) is located along longitudinal axis (L-L) so that its surface area corresponds to the above theoretical value (Ath). Inner casing (13) of fan preferably has the shape which at least approaches the barrel; at that, throat (T) of cold flow nozzle is located behind the largest cross section (23) of fan inner casing (13).

EFFECT: achieving preliminary adaptation of nozzle to cruise flight phase.

7 cl, 3 dwg