TURBOJET ENGINE WITH CONTROLLABLE BYPASS RATIO Russian patent published in 2002 - IPC

FIELD: aeronautical engineering. SUBSTANCE: turbojet engine has low and high pressure compressors, combustion chamber, high and low pressure turbines with behind-the-turbine fairing arranged in tandem along flow, bypass channel connecting inner space behind low pressure compressor with behind-the turbine channel, bypass valve connected with drive to provide its opening and closing. Connection of inner space of bypass channel is effected through hollow streamlined radial ribs installed over circumference behind low pressure turbine, space being connected with inner space of scroll collector placed inside behind-the-turbine fairing provided with bottom step with hole in center. Collector outlet is connected with hollow elbow branch pipe accommodating bypass valve. Elbow branch pipe terminates in head whose outlet section is located not farther than outlet plane of behind-the-turbine fairing. Shape of behind-the-turbine channel is confuser whose minimum section is located in cross plane of bottom step of behind-the-turbine fairing. Ratio of area of outlet to area of confuser inlet should be so as provide positive difference between total pressure in outlet section of elbow branch pipe and static pressure in behind-the-turbine space. EFFECT: provision of high thrust performance at augmented and maximum power with good economy at subsonic cruising flight conditions and provision of simple and compact bypass circuit opening and closing device installed in pipe of relatively small diameter. 4 dwg