Abstract: A variable geometry turbine has annular inlet passageway defined between a first surface of a radial wall of a movable wall mounted within a cavity and a facing wall of the turbine housing. The radial wall defines a second surface that opposes the first surface. The moveable wall member comprises an annular flange that extends axially into the cavity and supports a radial flange defining opposing third and fourth surfaces. The radial flange seals against an annular sleeve in the cavity to define a first area within the cavity which includes the radial second and third surfaces and a second area within the cavity which includes the radial fourth surface. The first and second areas are in fluid communication with regions of the annular inlet passageway which are respectively upstream and downstream of a radial vane passage.

Abstract: A variable geometry turbine has annular inlet passageway defined between a first surface of a radial wall of a movable wall mounted within a cavity and a facing wall of the turbine housing. The radial wall defines a second surface that opposes the first surface. The moveable wall member comprises an annular flange that extends axially into the cavity and supports a radial flange defining opposing third and fourth surfaces. The radial flange seals against an annular sleeve in the cavity to define a first area within the cavity which includes the radial second and third surfaces and a second area within the cavity which includes the radial fourth surface. The first and second areas are in fluid communication with regions of the annular inlet passageway which are respectively upstream and downstream of a radial vane passage.