Unconvinced that the aerodynamics of a single blade in a wind tunnel would match the real world performance of a multi-stage compressor, the cascade allowed various compressor layouts to be tested simply by moving the plates on a mounting plate inside the wind tunnel.
42.
In the late 1980s, GE also proposed a much larger turboprop, the T407 / GLC38, with a five-stage axial / one-stage centrifugal mixed-flow compressor; an annular combustor with 15 burners; a two-stage compressor turbine; a three-stage power turbine; and max takeoff power of 6, 000 shp ( 4, 475 kW ).
43.
The Advance reverses this trend and the load is shifted towards the high pressure spool, with a greater pressure ratio, up to 10 stages compressor compared to 6 on the Trent XWB and a two-stage turbine against the current single-stage, while the IP compressor will shrink from the 8 stages of today s XWB to 4 and the IP turbine will be single instead of two stages.
44.
The initial " T700-GE-700 " is an ungeared free-turbine turboshaft, with a five-stage axial / one-stage centrifugal mixed-flow compressor, featuring one-piece " blisk " axial stages, with the inlet guide vanes and first two stator stages variable; an annular combustion chamber with central fuel injection to improve combustion and reduce smoke; a two-stage compressor turbine; and a two-stage free power turbine with tip-shrouded blades.
