Geometry regulating law of variable cycle engine during mode transition

The inertial rotor dynamics and volume dynamics of variable cycle engine were considered. The influences of mode selector valve area, core driven fan stage inlet guide vane, low pressure turbine area, nozzle throat area and their different combined adjustments on variable cycle engine mode transition performance were analyzed and compared with the test data. The results indicate that the simulation model established can calculate the characteristic of variable cycle engine mode transition correctly. It is suggested that the core driven fan stage inlet guide vane should been closed/opened when the mode selector valve area is opened/closed during mode transition. The parameters can change more smoothly by adding reasonable regulation of low pressure turbine area and nozzle throat area.