Abstract: The disclosure relates to an oil circulation system for a gas turbine engine, and in particular to a gas turbine engine comprising a bearing chamber with a plurality of oil injectors. Example embodiments include a gas turbine engine, comprising: a bearing chamber (301) surrounding a turbine shaft (308) of the engine; an oil feed injection line (305) arranged to supply oil from an oil collecting compartment to a plurality of oil injectors (306, 401, 402) within the bearing chamber (301); an oil exit pipe (309, 313) arranged to allow oil to exit the bearing chamber (301); and an oil supply pump arranged to recirculate oil from the oil collecting compartment to the oil feed injection line (305), wherein the plurality of oil injectors comprise an injector (401, 402) arranged to direct oil towards an inlet of the oil exit pipe (309, 313).

Abstract: A hydraulic seal arrangement for a rotating machine, particularly a gas turbine engine, comprises a hydraulic seal and a hydraulic trap. When the machine is shut down, oil is retained in the hydraulic trap. When the machine is restarted, the oil from the hydraulic trap is available to re-make the hydraulic seal, thereby reducing or avoiding the leakage that typically occurs in such seal arrangements until the flow of oil through the seal arrangement is re-established.

Abstract: There is disclosed a lubricant scavenge arrangement provided on a chamber having an outer wall and configured to house a lubricated rotative component for rotation about an axis. The scavenge arrangement comprises: a substantially elongate channel provided in a substantially arcuate region of the wall, the channel being open to the chamber over substantially its entire length between an inlet end and an outlet end, said inlet end and said outlet end being angularly spaced apart around said longitudinal axis. The scavenge arrangement is particularly suited to use on bearing chambers in gas turbine engines.

Abstract: A hydraulic seal arrangement for a rotating machine, particularly a gas turbine engine, comprises a hydraulic seal and a hydraulic trap. When the machine is shut down, oil is retained in the hydraulic trap. When the machine is restarted, the oil from the hydraulic trap is available to re-make the hydraulic seal, thereby reducing or avoiding the leakage that typically occurs in such seal arrangements until the flow of oil through the seal arrangement is re-established.

Abstract: There is disclosed a lubricant scavenge arrangement provided on a chamber having an outer wall and configured to house a lubricated rotative component for rotation about an axis. The scavenge arrangement comprises: a substantially elongate channel provided in a substantially arcuate region of the wall, the channel being open to the chamber over substantially its entire length between an inlet end and an outlet end, said inlet end and said outlet lo end being angularly spaced apart around said longitudinal axis. The scavenge arrangement is particularly suited to use on bearing chambers in gas turbine engines.