Abstract: An actuation system 100 comprises a fluid supply 130 that is fluidly connected to a position control actuator 110. The output of the position control actuator is determined by the fluid supply. The fluid supply is controlled by a piezoelectric actuator 150.

Abstract: A centrifugal debris separator for removing debris from a gas turbine engine fuel system comprises a debris separator inlet, a debris separator outlet and a separating chamber with a centerline extending in an axial direction and defined by an outer wall formed around the centerline. The separating chamber comprises a separating chamber inlet for receiving fluid, a first separator outlet to the separating chamber, a second separator outlet to the separating chamber provided to the outer wall of the separating chamber and a third separator outlet to the separating chamber defined by a third separator outlet wall formed around the centerline of the separating chamber. The debris separator inlet is fluidly connected to the separating chamber inlet. The debris separator outlet is fluidly connected to the first separator outlet.

Abstract: A centrifugal debris separator for removing debris from a gas turbine engine fuel system comprises a debris separator inlet, a debris separator outlet and a separating chamber with a centreline extending in an axial direction and defined by an outer wall formed around the centreline. The separating chamber comprises a separating chamber inlet for receiving fluid, a first separator outlet to the separating chamber, a second separator outlet to the separating chamber provided to the outer wall of the separating chamber and a third separator outlet to the separating chamber defined by a third separator outlet wall formed around the centreline of the separating chamber. The debris separator inlet is fluidly connected to the separating chamber inlet. The debris separator outlet is fluidly connected to the first separator outlet.

Abstract: An actuation system 100 comprises a fluid supply 130 that is fluidly connected to a position control actuator 110. The output of the position control actuator is determined by the fluid supply. The fluid supply is controlled by a piezoelectric actuator 150.

Abstract: A clearance control apparatus for controlling the clearance between a rotary assembly (17) and a casing (24) surrounding the rotary assembly (17) is disclosed. The clearance control apparatus comprises a temperature measuring device (34) to measure the temperature of a radially outer portion of the rotary assembly and a cooling arrangement (28) to cool the casing (24). A control system (36) is associated with the temperature measuring device (34) and the cooling arrangement (28) to control the extent of cooling of the casing (24). The extent of cooling is dependent upon the temperature of the aforesaid portion.

Abstract: A clearance control apparatus for controlling the clearance between a rotary assembly (17) and a casing (24) surrounding the rotary assembly (17) is disclosed. The clearance control apparatus comprises a temperature measuring device (34) to measure the temperature of a radially outer portion of the rotary assembly and a cooling arrangement (28) to cool the casing (24). A control system (36) is associated with the temperature measuring device (34) and the cooling arrangement (28) to control the extent of cooling of the casing (24). The extent of cooling is dependent upon the temperature of the aforesaid portion.