Abstract: A system for fan stress tracking according to an example of the present disclosure includes, among other things, a computing device that has a memory and a processor. The computing device is operable to execute a data module and a comparison module. The data module is operable to access data corresponding to a sensed value of an engine inlet parameter, and is operable to access data corresponding to a fan stress fatigue ratio profile. The fan stress fatigue ratio profile is defined with respect to at least one fan blade. The comparison module is operable to associate the sensed value of the engine inlet parameter with a stress value according to the fan stress fatigue ratio profile. The comparison module is operable to determine whether the stress value meets at least one predetermined criterion.

Abstract: A method of thrust reversal operation according to an example of the present disclosure includes, among other things, permitting an increase in engine power when at least one criterion is not met and a thrust reverser is deployed, and denying the increase in engine power when the at least one criterion is met. A system for thrust reversal is also disclosed.

Abstract: A method for manufacturing long lasting phosphorescent fabrics and articles of clothing including fabric for use in fields such as security, domestic, sports, health, professional, etc., includes (i) preparing a composition for dyeing having a strontium aluminate pigment doped with europium and dysprosium; (ii) coating a starting fabric with the composition by air knife coating or cylinder; (iii) drying; and (iv) polymerizing. The fabrics thus obtained have long lasting phosphorescent properties and a high resistance to washing, maintaining the factory specifications of the starting fabric with respect to its mechanical properties, comfort, breathability and/or high visibility properties, if relevant.

Abstract: The disclosure provides a passive pressure drag reduction apparatus. The apparatus comprises a housing (106) comprising a base face (114), an open top face (110) opposite the base face and at least one side face (108) extending between the base face and the top face, wherein the base face, the top face and the at least one side face define a cavity (102). A panel (112) is aligned with the top face of the housing, and there is provided an aperture (104) extending around the panel, wherein the cavity is in fluid communication with an environment surrounding the apparatus via the aperture. Further, attachment means are provided arranged to secure the panel to the housing.

Abstract: A system for fan stress tracking according to an example of the present disclosure includes, among other things, a computing device that has a memory and a processor. The computing device is operable to execute a data module and a comparison module. The data module is operable to access data corresponding to a sensed value of an engine inlet parameter, and is operable to access data corresponding to a fan stress fatigue ratio profile. The fan stress fatigue ratio profile is defined with respect to at least one fan blade. The comparison module is operable to associate the sensed value of the engine inlet parameter with a stress value according to the fan stress fatigue ratio profile. The comparison module is operable to determine whether the stress value meets at least one predetermined criterion.

Abstract: A drag reduction apparatus for reducing the aerodynamic drag on a bluff body with a blunt trailing edge caused by fluid flow characteristics at the wake of the bluff body, the drag reduction apparatus comprising: one or more control elements configured to be coupled to the bluff body and to move with respect to the bluff body, whereby the movement of the one or more control elements controls fluid flow at the wake of the bluff body to reduce the drag caused by fluid flow instabilities and environmental asymmetries.

Abstract: The disclosure provides a passive pressure drag reduction apparatus. The apparatus comprises a housing (106) comprising a base face (114), an open top face (110) opposite the base face and at least one side face (108) extending between the base face and the top face, wherein the base face, the top face and the at least one side face define a cavity (102). A panel (112) is aligned with the top face of the housing, and there is provided an aperture (104) extending around the panel, wherein the cavity is in fluid communication with an environment surrounding the apparatus via the aperture. Further, attachment means are provided arranged to secure the panel to the housing.

Abstract: A method for manufacturing long lasting phosphorescent fabrics and articles of clothing including fabric for use in fields such as security, domestic, sports, health, professional, etc., includes (i) preparing a composition for dyeing having a strontium aluminate pigment doped with europium and dysprosium; (ii) coating a starting fabric with the composition by air knife coating or cylinder; (iii) drying; and (iv) polymerizing. The fabrics thus obtained have long lasting phosphorescent properties and a high resistance to washing, maintaining the factory specifications of the starting fabric with respect to its mechanical properties, comfort, breathability and/or high visibility properties, if relevant.

Abstract: A gas turbine engine comprises a compressor, a combustor, a turbine, and an electronic engine control system. The compressor, combustor, and turbine are arranged in flow series. The electronic engine control system is configured to generate a real-time estimate of compressor stall margin from an engine model, and command engine actuators to correct for the difference between the real time estimate of compressor stall margin and a required stall margin.

Abstract: A method of thrust reversal operation according to an example of the present disclosure includes, among other things, permitting an increase in engine power when at least one criterion is not met and a thrust reverser is deployed, and denying the increase in engine power when the at least one criterion is met. A system for thrust reversal is also disclosed.

Abstract: A vehicle comprising at least one pressure-drag-reducing apparatus (1) for reducing the pressure drag on the vehicle. The apparatus comprises: a housing (31) at least partly defining a cavity (34) and an aperture (35) in the housing (31), the cavity (34) in fluid communication via the aperture (35) with the environment surrounding the vehicle; and oscillating means (32, 36) for creating an oscillation in pressure across the aperture between the cavity and the environment. The cavity volume, the frequency of oscillation, the aperture size and the amplitude of oscillation are arranged to cause fluid to be alternately drawn into, and ejected from, the cavity through the aperture. The apparatus is positioned relative to the remainder of the vehicle such that the ejected fluid entrains fluid from the environment to reduce pressure drag on the vehicle.

Abstract: A vehicle comprising at least one pressure-drag-reducing apparatus (1) for reducing the pressure drag on the vehicle. The apparatus comprises: a housing (31) at least partly defining a cavity (34) and an aperture (35) in the housing (31), the cavity (34) in fluid communication via the aperture (35) with the environment surrounding the vehicle; and oscillating means (32, 36) for creating an oscillation in pressure across the aperture between the cavity and the environment. The cavity volume, the frequency of oscillation, the aperture size and the amplitude of oscillation are arranged to cause fluid to be alternately drawn into, and ejected from, the cavity through the aperture. The apparatus is positioned relative to the remainder of the vehicle such that the ejected fluid entrains fluid from the environment to reduce pressure drag on the vehicle.

Abstract: A liquid storage closure device (10) and methods of using the same are disclosed. The device may comprise a cover (12) capable of being attached to a liquid storage container (14), wherein the cover comprises an opening (22) allowing liquid to pass through. The device may also comprise an outer straw (16) inserted within the liquid storage container (14) and an inner straw (18) slidingly and sealingly received within the outer straw (16) and the opening (22), such that liquid is capable of passing from the liquid storage container (14), through a lower end of the outer straw (16) disposed therein, and out an upper end of the inner straw (18). In some embodiments, the device may also comprise a cap (20) capable of being sealingly attached to the cover (12) such that liquid is substantially retained within the liquid storage container (14).

Abstract: A gas turbine engine comprises a compressor, a combustor, a turbine, and an electronic engine control system. The compressor, combustor, and turbine are arranged in flow series. The electronic engine control system is configured to generate a real-time estimate of compressor stall margin from an engine model, and command engine actuators to correct for the difference between the real time estimate of compressor stall margin and a required stall margin.

Abstract: A structural element made of a composite material includes a plurality of modular cells disposed within the composite material that have tensile elements that create axially directed tension anchoring elements attached to the tensile elements that create compression with anchoring elements of proximate modular cells. The modular cells may be disposed randomly or in a patterned manner within the composite material. A stackable structural cell facilitates more efficient creation of beams or columns and can include rebar for some of the tension elements that are axially arranged. Additionally, modular cells and/or supported capsules may be added to increase tension and/or decrease mass or weight of the beam or column. The structural cell can further include a boundary layer for containing the composite material prior to hardening.

Abstract: Time responsiveness to thrust demands for a fan jet engine of the type that includes twin spools and a variable inlet at the fan is enhanced by regulating air flow through the variable inlet while holding low pressure compressor speed constant. The thrust change is targeted as a function of power lever position which generates a low pressure compressor parameter as a function of engine and aircraft operating variables. This parameter is then utilized to control both the inlet variable vanes and fuel flow to 1) attain the targeted value and 2) return the engine to its steady state operating line after a given time interval.

Abstract: An active control system for use in gas turbine engines synchronizes exhaust nozzle area and burner fuel flow together with pas path variable engine parameters, such as fan variable vane and high compressor variable vane positions. As a result, extremely fast thrust transients are possible with optimized compression system stability, since fan and compressor rotor speeds are held high, allowing total engine power to be controlled by air flow and fuel flows directly.

Abstract: The time responsiveness and engine stability for an acceleration and deceleration engine transient is enhanced by a control mechanism that synchronously adjusts fuel flow and high pressure compressor vane position as a function of corrected low pressure compressor speed in a twin spool axial flow turbine power plant. The acceleration and deceleration mode is targeted by power lever position and the target is attained by adjusting the vane position at a constant high pressure compressor speed and returned to a fuel efficient and engine stable steady state operating line by concomittantly adjusting fuel flow and vane position.