Abstract: A passive heat exchanger includes an evaporator section including a heat exchange surface formed complementary to a surface of a gas turbine engine component to be cooled. The heat exchange surface is configured to be thermally coupled in conductive contact to the component surface. The heat exchanger further includes a condenser section coupled in passive convective flow communication with the evaporator section, and a working fluid contained within the evaporator section and the condenser section and configured to passively convect heat from the evaporator section to the condenser section.

Abstract: The rotatable machine includes a compressor and an inner annular casing circumscribing at least a portion of the compressor. The inner annular casing includes an outer surface in a radial direction, an upper portion in a vertical direction, and a lower portion in a vertical direction. The clearance control system includes a manifold system including at least one conduit extending circumferentially around the lower portion of the inner annular casing. The clearance control system includes a header system including at least one header extending circumferentially around only the lower portion of the inner annular casing. The at least one header configured to receive a flow of cooling fluid from the at least one conduit. The at least one header configured to channel the flow of cooling fluid to the lower portion of the outer surface of the inner annular casing.

Abstract: The rotatable machine includes a compressor and an inner annular casing circumscribing at least a portion of the compressor. The inner annular casing includes a radially outer surface. The inner annular casing includes a radially outer surface, a vertically upper portion, and a vertically lower portion. The clearance control system includes a manifold system including a manifold system includes at least one conduit extending circumferentially around the vertically lower portion of the inner annular casing. The clearance control system includes a header system including at least one header extending circumferentially around only the vertically lower portion of the inner annular casing. The at least one header configured to receive a flow of cooling fluid from the at least one conduit. The at least one header configured to channel the flow of cooling fluid to the vertically lower portion of the radially outer surface of the inner annular casing.

Abstract: A passive heat exchanger includes an evaporator section including a heat exchange surface formed complementary to a surface of a gas turbine engine component to be cooled. The heat exchange surface is configured to be thermally coupled in conductive contact to the component surface. The heat exchanger further includes a condenser section coupled in passive convective flow communication with the evaporator section, and a working fluid contained within the evaporator section and the condenser section and configured to passively convect heat from the evaporator section to the condenser section.

Abstract: A method of mitigating soak-back in a gas turbine engine including an engine core compartment and an active engine core compartment cooling system are provided. The active engine core compartment cooling system includes an aperture extending through a core engine cowl forming a radially outer wall of the engine core compartment. The active engine core compartment cooling system also includes a cooling fan mounted within the engine core compartment and including a cooling fan inlet and a cooling fan outlet. The cooling fan inlet is coupled in flow communication with the aperture. The cooling fan outlet is coupled in flow communication with the engine core compartment. The active engine core compartment cooling system further includes a cooling fan controller configured to at least one of control a rotational speed of the cooling fan and control a position of at least one flow control valve coupled in series flow communication with the cooling fan.

Abstract: A system for cooling an equipment compartment of a gas turbine engine includes a cooling manifold for directing cooling air from outside of the equipment compartment to within the equipment compartment, a temperature sensor disposed within the equipment compartment, an electronically controlled cooling valve configured to control the volume of air flowing through said cooling manifold, and a control unit configured to receive electronic data information from the temperature sensor and transmit electronic data information to the electronically controlled cooling valve based on electronic information received from said temperature sensor.

Abstract: A thermally actuated venting system includes a thermally actuated vent for opening a vent outlet in a gas turbine engine associated compartment with a passive thermal actuator located in the compartment based on a temperature of the compartment. Outlet may be located at or near a top of a core engine compartment, a fan compartment, or a pylon compartment. Actuator may be operably connected to a hinged door of vent for opening outlet. Actuator may be actuated by a phase change material disposed in a chamber and having a liquid state below a predetermined actuation temperature and a gaseous state above the predetermined actuation temperature. Actuator may include a thermal fuse for closing door during a fire. Thermal fuse may include at least a portion of piston rod or a cylinder wall of actuator being made of a fuse material having a melting point substantially above the predetermined actuation temperature.

Abstract: A flow device adapted to operate as a restrictor as well as provide a pressure relief capability in the event of an over-pressurization event within a fluid system containing the device. The flow device includes an expandable orifice that has an outer perimeter, a plurality of cantilevered tabs surrounded by the outer perimeter, and an opening surrounded and defined by the tabs. The tabs project from the outer perimeter toward the opening, which restricts flow of the bleed air through the expandable orifice at a pressure below a predetermined pressure level, but then expands to relieve an over-pressure condition of the bleed air at a pressure above the predetermined pressure level as a result of the cantilevered tabs being deflected by the over-pressure condition. The device is adaptable for use in aircraft applications, including the regulation of bleed air used in anti-icing/de-icing systems.

Abstract: A flow device adapted to operate as a restrictor as well as provide a pressure relief capability in the event of an over-pressurization event within a fluid system containing the device. The flow device includes an expandable orifice that has an outer perimeter, a plurality of cantilevered tabs surrounded by the outer perimeter, and an opening surrounded and defined by the tabs. The tabs project from the outer perimeter toward the opening, which restricts flow of the bleed air through the expandable orifice at a pressure below a predetermined pressure level, but then expands to relieve an over-pressure condition of the bleed air at a pressure above the predetermined pressure level as a result of the cantilevered tabs being deflected by the over-pressure condition. The device is adaptable for use in aircraft applications, including the regulation of bleed air used in anti-icing/de-icing systems.

Abstract: A thermally actuated venting system includes a thermally actuated vent for opening a vent outlet in a gas turbine engine associated compartment with a passive thermal actuator located in the compartment based on a temperature of the compartment. Outlet may be located at or near a top of a core engine compartment, a fan compartment, or a pylon compartment. Actuator may be operably connected to a hinged door of vent for opening outlet. Actuator may be actuated by a phase change material disposed in a chamber and having a liquid state below a predetermined actuation temperature and a gaseous state above the predetermined actuation temperature. Actuator may include a thermal fuse for closing door during a fire. Thermal fuse may include at least a portion of piston rod or a cylinder wall of actuator being made of a fuse material having a melting point substantially above the predetermined actuation temperature.

Abstract: Aircraft aerodynamic surfaces coated with photocatalytic self-cleaning coating reduces the need for washing off insects and other organic contaminants. Disturbances in laminar flow profiles due to organic contaminants are reduced, thereby improving performance by reducing drag. The photocatalytic self-cleaning coating includes nano-particles of titanium oxide and may be applied using a sol-gel process.

Abstract: A gas turbine engine includes an engine core extending along a core axis, a cooling-air delivery duct on the engine core, and a removable nacelle cowl overlying the engine core. A cooling-air nacelle-cowl duct delivers cooling air to the cooling-air delivery duct. At least a portion of the length of the cooling-air nacelle-cowl duct is integral with the nacelle cowl and not directly supported on the engine core.

Abstract: A gas turbine engine includes an engine core extending along a core axis, a cooling-air delivery duct on the engine core, and a removable nacelle cowl overlying the engine core. A cooling-air nacelle-cowl duct delivers cooling air to the cooling-air delivery duct. At least a portion of the length of the cooling-air nacelle-cowl duct is integral with the nacelle cowl and not directly supported on the engine core.

Abstract: An icing protection system and method for enhancing heat transfer includes a substrate having an inner wall, an outer wall and a thickness separating the inner wall and the outer wall. A metallic layer deposited on the inner wall of the substrate by an electric arc thermal spray deposition process using at least one metallic wire has a thickness between about 0.203 mm (0.008 inches) and about 0.432 mm (0.017 inches), a surface roughness greater than about 12.7 microns (500 micro-inches) Ra, and a heat transfer augmentation of at least about 1.1. The metallic layer is formed on the inner wall from an M-Cr—Al alloy where M is selected from Fe, Co and Ni. The metallic layer defines a plurality of turbulators that act as micro-fins to enhance heat transfer from a heated gas in flow communication with the metallic layer through the substrate to prevent the formation of ice on the outer wall.