GAS TURBINE PROPFAN ENGINE Russian patent published in 2012 - IPC F02K3/62 

FIELD: engines and pumps.

SUBSTANCE: gas turbine propfan engine with rear arrangement of propfan rotors comprises a gas generator with a compressor, a gas channel in a propfan bushing, a nozzle. In the gas channel there are hollow stands of propfan rotors. At the outer side from the gas channel of the propfan bushing there is an outer circular air cavity connected at the inlet to the intermediate stage of the low pressure compressor, and at the outlet - via hollow stands of propfan rotors with an additional axial nozzle in a bushing fairing. The outer circular air cavity is separated from atmosphere with an outer shell with radial ribs directed towards the bushing axis, where labyrinth seals are arranged. Ratio of the nozzle area at the outlet from the propfan bushing gas channel to the area of the additional axial nozzle in the propfan bushing fairing makes 5…20. The ratio of the outer diameter of the propfan bushing to the average diameter of labyrinth seals of propfan rotors makes 1.05…1.20.

EFFECT: higher cost-effectiveness and reliability of a gas turbine propfan engine by reduction of parasite leakages of gas from a propfan bushing into atmosphere and also by use of air spent in a cooling system of a propfan bushing to develop gas turbine engine thrust.

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