| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a variable cycle engine including a low-bypass ratio turbofan to be used as a propeller of a small supersonic airplane, driven by a small engine, and comprising a simpler variable mechanism. <P>SOLUTION: A tail cone installed in a core duct outlet immediately under a low-pressure turbine is allowed to move longitudinally. The low-pressure turbine expansion ratio is increased/decreased by changing the core duct outlet area when the movable tail cone moves longitudinally. The bypass ratio can be varied in response to a change in fan rotating speed. During takeoff, an exhaust speed is reduced and thrust is increased. During transonic speed increase and supersonic speed cruising, when the turbine inlet temperature and the whole pressure ratio are enhanced, an increase in the fan rotating speed is controlled to achieve high thrust. <P>COPYRIGHT: (C)2013,JPO&INPIT |
