CENTRIFUGAL COMPRESSOR FORWARD THRUST AND TURBINE COOLING APPARATUS

摘要

A gas turbine engine centrifugal compressor axial forward thrust apparatus bleeds impeller tip aft bleed flow from between an annular centrifugal compressor impeller of a high pressure rotor and a diffuser directly downstream of the impeller. The apparatus then uses the aft bleed flow to pressurize an annular cavity extending radially between an inner combustor casing and the rotor and extending axially between forward and aft thrust balance seals. Forward and aft thrust balance lands are in sealing engagement with the forward and aft thrust balance seals on the high pressure rotor respectively. An annular stator plenum in fluid communication with the annular cavity is bounded in part by a forward end wall having conical diffusion holes therethrough which may be axially or circumferentially or axially and circumferentially angled. The forward thrust balance seal may be on an aft conical arm of the impeller.