GAS TURBINE ENGINE Russian patent published in 2019 - IPC F02K3/06 F02K1/06 B64D27/26 

FIELD: engines.

SUBSTANCE: gas turbine engine comprises a gear train defined along an engine centerline axis, cascade, fan nacelle, core nacelle, fan, fan nozzle and inner circuit. Cascade is designed to drive the gear train and comprises a low-pressure turbine with a number of stages from three to six. Fan nacelle is mounted around the inner nacelle and defines the path for the airflow of the outer fan circuit, wherein the degree of double circuit is more than six. Fan nozzle is made with a variable cross-sectional area and is movable axially relative to the fan nacelle in order to change the area of the exit section of the fan nozzle and adjust the airflow in the outer circuit of the fan during engine operation. Fan is rotatable at a fan speed around the longitudinal axis and is driven by a low pressure turbine by means of a gear train, and the fan speed is lower than that of the low-pressure turbine. Inner circuit is surrounded by the core nacelle. Gear train has a gear ratio greater than or equal to 2.3, wherein the minimum ratio of pressure in the fan is less than 1.45, and the minimum circumferential speed of the fan blade is less than 1150 ft/s (350.5 m/s).

EFFECT: invention provides a lighter structure of the gas turbine engine, and also reduces the noise produced by the fan.

13 cl, 15 dwg