Systems and methods for operating systems are provided. For example, a system comprises a coolant flowpath having a coolant flowing therethrough, a cooling system for cooling the coolant disposed along the coolant flowpath, a fuel flowpath having a fuel flowing therethrough, a heat exchanger fluidly connected to the coolant flowpath and the fuel flowpath for heat transfer between the coolant and the fuel to cool the fuel, and a fuel tank for accumulating the cooled fuel. The fuel is in thermal communication with a first thermal load to cool the load. An exemplary method comprises flowing a heat exchange fluid along a flowpath; flowing a fuel along a fuel flowpath including a fuel tank; passing both the heat exchange fluid and fuel through a heat exchanger to cool the fuel; and controlling the fuel flow from the heat exchanger to the fuel tank for accumulation of the cooled fuel.

A system for monitoring fuel additives on board a vehicle includes a fuel line carrying fuel from a fuel source to an engine; a fuel additive sensor configured to measure concentration of additives in fuel at a point along the fuel line; a fuel additive dispenser connected in parallel to the fuel line; at least one flow control device for controlling an amount of flow from the fuel line into the fuel additive dispenser; and a controller configured to receive input from the fuel additive sensor and to control the flow control device to adjust the amount of the flow from the fuel line into the fuel additive dispenser.

A passive flow splitting system for use in a turbine engine control system to provide split fuel flow to two fuel manifolds to supply primary and secondary fuel injectors for the particular combustion zones thereof utilizing intentionally different split ratios dependent on ascending or descending combustion fuel flow is provided. The system includes a passive fuel divider valve (FDV) that includes a primary piston and a secondary piston. The primary piston is moveable independently from the secondary piston during a portion of its stroke, and is hydro-locked to the secondary piston during another portion of its stroke. An ecology valve is also provided to purge the fuel from the primary and/or secondary manifolds during different modes of operation. A transfer valve is included to control the position of ecology piston of the ecology valve.

A turbine case cooling system including a turbine assembly having an inlet and an outlet and surrounded by a turbine casing. The turbine case cooling system is arranged to selectively impingement cool at least part of the turbine casing. The system includes an annular structure that is radially spaced from the turbine casing and includes a downstream end. The system includes an annular duct that is spaced radially outwardly from the turbine casing and radially inwardly from the annular structure. The duct is sealingly coupled to the turbine casing at a first end towards the turbine inlet, and a second end extends axially towards the downstream end of the annular structure and the turbine outlet.

A fan casing assembly, connection assembly and method for moving a fan casing cooler. The fan casing assembly for the turbine engine can include an annular fan casing with a peripheral wall having a flow path defined through the casing. A fan casing cooler can mount along the peripheral wall in order to confront a cooling fluid flow within the flow path in order to cool a fluid through the fan casing cooler.

A system for monitoring fuel additives on board a vehicle includes a fuel line carrying fuel from a fuel source to an engine; a fuel additive sensor configured to measure concentration of additives in fuel at a point along the fuel line; a fuel additive dispenser connected in parallel to the fuel line; at least one flow control device for controlling an amount of flow from the fuel line into the fuel additive dispenser; and a controller configured to receive input from the fuel additive sensor and to control the flow control device to adjust the amount of the flow from the fuel line into the fuel additive dispenser.

A gas turbine engine includes, among other things, a propulsor section including a rotor, a gear train, a low spool and a high spool. A static structure includes a first case and a second case. A mount system includes a forward mount and an aft mount arranged in a plane containing an engine axis of rotation. The forward mount is secured to the first case. The aft mount is secured to the second case.

Systems and methods for operating systems are provided. For example, a system comprises a coolant flowpath having a coolant flowing therethrough, a cooling system for cooling the coolant disposed along the coolant flowpath, a fuel flowpath having a fuel flowing therethrough, a heat exchanger fluidly connected to the coolant flowpath and the fuel flowpath for heat transfer between the coolant and the fuel to cool the fuel, and a fuel tank for accumulating the cooled fuel. The fuel is in thermal communication with a first thermal load to cool the load. An exemplary method comprises flowing a heat exchange fluid along a flowpath; flowing a fuel along a fuel flowpath including a fuel tank; passing both the heat exchange fluid and fuel through a heat exchanger to cool the fuel; and controlling the fuel flow from the heat exchanger to the fuel tank for accumulation of the cooled fuel.

A bleed valve includes a housing with an inlet coupled to an outlet by a duct, a guide tube with an orifice fixed in the housing between the inlet and the outlet, a piston, and baffle. The piston is slideably supported on the guide tube and is movable between an open and a closed position, the duct fluidly coupling the inlet and outlet in the open position, the duct fluidly separating the inlet and outlet in the closed position. The orifice fluidly couples the inlet and outlet in the open and closed positions to move piston between the open and closed positions according to differential pressure between the bleed valve inlet and outlet. The baffle is slideably supported by the guide tube to set the differential pressure at which the piston moves between the open and closed positions. Gas turbines and differential pressure adjustment methods are also described.

A passive flow splitting system for use in a turbine engine control system to provide split fuel flow to two fuel manifolds to supply primary and secondary fuel injectors for the particular combustion zones thereof utilizing intentionally different split ratios dependent on ascending or descending combustion fuel flow is provided. The system includes a passive fuel divider valve (FDV) that includes a primary piston and a secondary piston. The primary piston is moveable independently from the secondary piston during a portion of its stroke, and is hydro-locked to the secondary piston during another portion of its stroke. An ecology valve is also provided to purge the fuel from the primary and/or secondary manifolds during different modes of operation. A transfer valve is included to control the position of ecology piston of the ecology valve.