Continuous stacked dual wrap tube end closure for anti-icing systems

An anti-icing system may comprise a deicing boot of an elastomeric material comprising a plurality of tubes, wherein the deicing boot comprises a first set of tubes and a second set of tubes, wherein each of the first set of tubes and the second set of tubes have a corresponding end, and wherein the corresponding end is coupled to a continuous dual wrap end closure.

FIELD

The disclosure relates generally to ice protection systems, more specifically, to anti-icing or ice protection systems for aircraft including mechanical elements.

BACKGROUND

In operation, aircraft may experience conditions in which icing may occur. For example, a propel blade of an aircraft, as well as other parts of the aircraft such as the wing leading edge or the empennage, may experience the formation of ice when operating in cold or below-freezing temperatures. The formation of such ice may dramatically alter one or more flight characteristics of the aircraft. For example, the formation of ice may deleteriously affect the aerodynamics of the aircraft and add additional undesirable weight, induce undesirable vibrations, as well as generate a hazard when such ice breaks off and potentially strikes another portion of the aircraft. For example, ice breaking loose from the aircraft may be ingested by the aircraft engine, thereby damaging the engine, or may strike the fuselage or other aerodynamic surfaces.

SUMMARY

In various embodiments, anti-icing system is disclosed comprising a deicing boot of an elastomeric material comprising a plurality of tubes, wherein the deicing boot comprises a first set of tubes and a second set of tubes, wherein each of the first set of tubes and the second set of tubes have a first end and a second end, and wherein at least one of the first end or the second end includes a continuous dual wrap end closure.

In various embodiments, the elastomeric material comprises at least one of a synthetic rubber, a natural rubber, or a polyurethane. In various embodiments, the first set of tubes extends along an axis parallel to the second set of tubes. In various embodiments, the anti-icing system includes a second deicing boot of the elastomeric material. In various embodiments, the continuous dual wrap end closure comprises a continuous non-elastomeric tape. In various embodiments, the continuous non-elastomeric tape defines a first layer and a second layer. In various embodiments, the ends of the first set of tubes are enclosed by the first layer and the ends of the second set of tubes are enclosed by the second layer. In various embodiments, each of the plurality of tubes are coupled relatively between a separating strip, wherein an end portion of the separating strip is enclosed by the first layer. In various embodiments, a gum ply layer is bonded relatively between the first layer and the second layer. In various embodiments, a first midline strip is bonded along a dorsal surface midline of the first layer.

In various embodiments control system for an anti-icing system is disclosed comprising a deicing boot, a controller, and a tangible, non-transitory memory configured to communicate with the controller, the tangible, non-transitory memory having instructions stored thereon that, in response to execution by the controller, cause the controller to perform operations comprising receiving an enable command from a control interface, polling a sensor for a sensor data, receiving the sensor data from the sensor, passing the sensor data to an ice protection logic, determining via the ice protection logic an icing condition, and providing a compressed gas to the deicing boot.

In various embodiments, the sensor data includes an air temperature data and a liquid water content data, wherein the ice protection logic determines the icing condition based on the air temperature data and the liquid water content data. In various embodiments, the operations further comprise receiving an activate command from the control interface, passing the activate command to the ice protection logic, and commanding the source of compressed gas to supply the compressed gas to the deicing boot via the ice protection logic and in response to the activate command. In various embodiments, the deicing boot comprises an elastomeric material having a plurality of tubes, wherein the plurality of tubes of the deicing boot includes a first set of tubes and a second set of tubes, and wherein the operations further comprise inflating the first set of tubes with the compressed, inflating the second set of tubes with the compressed, and inflating the first set of tubes and the second set of tubes with the compressed gas simultaneously. In various embodiments, each of the first set of tubes and the second set of tubes have a corresponding end, and wherein the corresponding end is coupled to a continuous dual wrap end closure. In various embodiments, the continuous dual wrap end closure comprises a continuous non-elastomeric tape. In various embodiments, the continuous non-elastomeric tape defines a first layer and a second layer, wherein the ends of the first set of tubes are enclosed by the first layer and the ends of the second set of tubes are enclosed by the second layer. In various embodiments, each of the plurality of tubes are coupled relatively between a separating strip, wherein an end portion of the separating strip is enclosed by the first layer, wherein a gum ply layer is bonded relatively between the first layer and the second layer, and wherein first midline strip is bonded along a dorsal surface midline of the first layer.

In various embodiments, a method of de-icing comprises receiving, by a controller, an enable command from a control interface, polling, by the controller, a sensor for a sensor data, receiving, by the controller, the sensor data from the sensor, passing, by the controller, the sensor data to an ice protection logic, determining, by the controller via the ice protection logic, an icing condition, and commanding, by the controller, a source of compressed gas to supply a compressed gas to the deicing boot, wherein the sensor data includes an air temperature data and a liquid water content data, wherein the ice protection logic determines the icing condition based on the air temperature data and the liquid water content data.

In various embodiments, the method may include receiving an activate command from the control interface, passing the activate command to the ice protection logic, and commanding via the ice protection logic and in response to the activate command the source of compressed gas to supply the compressed gas to the deicing boot. The method may include inflating a first set of tubes with the compressed gas, inflating a second set of tubes with the compressed gas, and inflating the first set of tubes and the second set of tubes with the compressed gas simultaneously, wherein the deicing boot comprises an elastomeric material having a plurality of tubes, wherein the plurality of tubes of the deicing boot includes the first set of tubes and the second set of tubes.

DETAILED DESCRIPTION

The use of terms such as “above,” “below,” “upper,” “lower,” “forward,” “aft”, “inboard”, “outboard”, “dorsal”, “ventral” or other like terms to describe a spatial relationship between various components or to describe the spatial orientation of aspects of such components should be understood to describe a relative relationship between the components or a spatial orientation of aspects of such components, respectively, as the device described herein may be oriented in any desired direction.

In various embodiments and with reference toFIGS.1A and1B, an aircraft such as, for example, tiltrotor aircraft101is illustrated. Although depicted with reference to tiltrotor aircraft101, it will be appreciated that the ice protection system and methods therefor may be used on other rotary aircraft, including helicopters, tilt wing aircrafts, quad til-trotor aircraft, unmanned aerial vehicles (UAVs), and other vertical lift or VTOL aircrafts, or can further be used with any device configured with a rotor blade and/or airfoil susceptible to an ice buildup, including fixed wing aircraft, turbine blades, devices with propellers, windmills, and wind turbines.

Tiltrotor aircraft101may include a fuselage103, a landing gear105, a tail member107, a wing109, a first propulsion system111, and a second propulsion system113. Each propulsion system111,113includes a fixed engine such as, for example, a gas turbine engine and a rotatable proprotor115,117, respectively. Each rotatable proprotor115,117has a plurality of rotor blades119,121, (i.e., proprotor blades) respectively, associated therewith. The position of proprotors115,117, as well as the pitch of rotor blades119,121, can be selectively controlled in order to selectively control direction, thrust, and lift of tiltrotor aircraft101.

FIG.1Aillustrates tiltrotor aircraft101in helicopter mode, in which proprotors115and117are positioned substantially vertical to provide a lifting thrust.FIG.1Billustrates tiltrotor aircraft101in an airplane mode, in which proprotors115,117are positioned substantially horizontal to provide a forward thrust in which a lifting force is supplied by wing109. It should be appreciated that tiltrotor aircraft can be operated such that proprotors115,117are selectively positioned between airplane mode and helicopter mode, which can be referred to as a conversion mode.

In various embodiments and with additional reference toFIG.2, a control system200for aircraft anti-icing is illustrated in accordance with various embodiments. Tiltrotor aircraft101includes a plurality of sensors202to monitor and measure characteristics of aircraft101. The sensors202may be coupled to or in direct electronic communication with aircraft systems such as, for example, propulsion systems111,113. The sensors202may comprise a temperature sensor, a torque sensor, a speed sensor, a pressure sensor, a position sensor, an accelerometer, or any other suitable measuring device known to those skilled in the art. The sensors202may be configured to measure a characteristic of an aircraft system or component. For example, the fuselage103may include a sensor123for sensing outside air temperature (OAT) and a sensor125for sensing the liquid water content (LWC) of the air passing over the fuselage103. Sensors202such as sensors123and125may be configured to transmit the measurements to a controller127, thereby providing sensor feedback about the aircraft system to controller127. The sensor feedback may be, for example, a speed signal, or may be position feedback, temperature feedback, pressure feedback or other data. In this regard, sensors123and125may be in electrical communication with a controller127.

In various embodiments, controller127may be in electronic communication with a pilot through a control interface175, for example, a set of switches, buttons, a multifunction display, and/or the like that a pilot can operate. The control interface175may display information such as sensor data from the sensors202or processed information from the controller127. The control interface may output command signals to the controller127in response to receiving an interaction via the control interface. In various embodiments, the command signals may be used as an input to an ice protection logic204of the controller127. The ice protection logic204may control, via controller127, various elements of an anti-icing system of the aircraft101such as, for example, one or more compressors and/or pneumatic valves.

In various embodiments, and with additional reference toFIGS.3A and3Ban exemplary airfoil300(e.g., such as one of rotor blades119,121or wing109) is illustrated.FIG.3Aillustrates partial perspective view of the airfoil300. Airfoil300may be is susceptible to an ice buildup. Airfoil300includes a spanwise axis302, a chordwise axis304, a leading edge306, a leading edge axis308, and a trailing edge310. As illustrated inFIG.3B, airfoil300comprises an anti-icing system400. Anti-icing system400may comprise one or deicing boots (e.g., a first deicing boot and a second deicing boot) of an elastomeric material which may be coupled to the leading edge306of the airfoil300as denoted by the shaded area.

An anti-icing system400includes one or more deicing boots (i.e., a first deicing boot, a second deicing boot, etc.) configured to mechanically disrupt ice formation at the leading edge of the airfoil300. The deicing boot along the spanwise axis302between the inboard and outboard edge of the airfoil300and wraps over the dorsal and ventral surface of the airfoil300. In this regard, the anti-icing system400extends along the chordwise axis304aft of the leading edge relatively above and below the leading edge axis308. Stated another way, the anti-icing system400including a deicing boot (such as, for example, deicing boot402) may be wrapped around the leading edge toward the trialing edge.

In various embodiments and with additional reference toFIGS.4A,4B, and4C, anti-icing system400is illustrated in perspective cross section in various stages of operation. Anti-icing system400includes a deicing boot402which may be coupled to an aircraft component susceptible to an ice buildup such as, for example, an inlet (e.g., oil cooler inlet, engine inlet, radiator inlet), a flight control structure, an airfoil (e.g., airfoil300as illustrated), an empennage, a fuselage, a wing, and/or any other desired aircraft part. Deicing boot402includes a plurality of tubes404. In various embodiments, the tubes404may be configured to include a first set406of tubes404, and second set408of tubes404. Each of tubes404includes first end410and second end412, with first end410disposed opposite second end412. Each of the tubes404may be closed at their respective ends410,412by an end closure, such as a continuous dual wrap end closure configured to inhibit fluid communication relatively between the first set406and the second set408of tubes. In this way, the tubes404may be configured, by the continuous dual wrap end closure, to inflate in response to receiving a compressed gas.

Tubes404are arranged in parallel next one another and each of tubes404can be arranged to extend chordwise transversely over leading edge306of airfoil300between first end410and second end412. In various embodiments, tubes404can be arranged generally parallel with the spanwise axis302along leading edge axis308. As shown inFIG.4A, all of tubes404are deflated when leading edge306of airfoil300is clear and free of ice. Should ice accumulate on leading edge306during operation of the aircraft, control system200may supply compressed gas (e.g., air from a source of compressed gas) to anti-icing system400. In this regard, the controller127may control the deicing boot402and the plurality of tubes404, a first manifold (not shown) inflates tubes404in first set406with air to break and remove the ice, as shown inFIG.4B. For example, the controller127may control a first valve in fluid communication between the first manifold and the source of compressed gas. After tubes404in first set406have been inflated, tubes404in second set408are inflated with air by a second manifold (not shown) while first set406of tubes404is deflated, as shown inFIG.4C. For example, the controller127may control a second valve in fluid communication between the second manifold and the source of compressed gas. In this regard, the controller127may enable alternating the inflation and deflation of first set406and second set408of tubes404tending thereby to allow the deicing boot402to operate with less disruption to airflow over the airfoil300. In various embodiments, the controller127may control the first set406and the second set408of tubes404to inflate simultaneously. In various embodiments, the tubes404may comprise an elastomeric material such as, for example, a synthetic rubber, silicone, a natural rubber, a polyurethane, and/or the like.

In various embodiments and with additional reference toFIGS.5A,5B,5C, and6an end (e.g. first end410or second end412) of tubes404is illustrated in perspective detail (FIGS.5A-5C) and cross section (FIG.6) showing the buildup of a continuous dual wrap end closure500. The end closure500comprises a continuous non-elastomeric tape502such as, for example, a bias cut polymer tape which is laid flat to form a first layer600. In various embodiments, a first midline strip504(i.e., a midline strip) may be bonded along a dorsal surface midline of the first layer600of the tape502. In this regard, the first midline strip504may divide the first layer600into an inboard portion506and an outboard portion508. Ends410of the first set406of the tubes404may abut the first midline strip504and may be bonded to the dorsal surface of the inboard portion506. In various embodiments, separating strips510may be interspersed between the tubes404and bonded therebetween. In like regard, the separating strips510may abut the first midline strip504and be bonded to the dorsal surface of inboard portion506of the first layer600.

Ends410of the second set408of tubes404may be folded relatively inboard and away (e.g., a folded end512) from the first layer600to provide clearance. The first layer600is folded (as indicated by arrow514) over the first set406of tubes404by bringing the outboard portion508across the midline strip504above the inboard portion506(i.e., respectively facing dorsal surfaces of the first layer600). The dorsal surface of outboard portion508may thereby be bonded to the first set406of tubes404by contacting the dorsal surface of the outboard portion508across the upper surface of the first set406of tubes404. In this regard, the first set406of tubes404may be enclosed in the first layer600of the continuous non-elastomeric tape502. In like regard, an end portion of the separating strips510is enclosed in the first layer600and bonded therebetween. The first midline strip504is similarly enclosed between the respective dorsal surfaces of the inboard portion506and the outboard portion508.

As shown inFIG.5B, in various embodiments a gum ply layer604may be bonded (e.g., between layers of rubber cement602as shown inFIG.6) to the first layer600. The continuous non-elastomeric tape502is drawn across the gum ply layer604and laid flat to form a second layer606of the tape502. In various embodiments, a second midline strip516may be bonded along a dorsal midline of the second layer606of the tape502. The second midline strip516may divide the second layer606into an inboard portion518and an outboard portion520. In this regard, the gum ply layer604may be bonded to the ventral surface of the outboard portion508of the first layer600and to the ventral surface of the inboard portion518of the second layer606(i.e., relatively between the first layer600and the second layer606). The folded ends512of the second set408of tubes404may be folded down contact the dorsal surface of second layer606. In various embodiments, the ends410of the second set408of tubes404may thereby abut the second midline strip516and be bonded to the inboard portion518and/or the second midline strip516.

In a similar manner, the second layer606is folded (as indicated by arrow522) over the second set408of tubes404by bringing the outboard portion520across the second midline strip516above the inboard portion518. The outboard portion520may thereby be bonded to the second set408of tubes404by contacting the dorsal surface of the outboard portion520across the upper surface of the second set408of tubes404. In this regard, the ends of the second set408of tubes404may be fully enclosed in the second layer606of the continuous non-elastomeric tape502as illustrated inFIG.5C.

In various embodiments, and with renewed reference toFIG.2, controller127may be integrated into computer systems onboard an aircraft, such as, for example, tiltrotor aircraft101. In various embodiments, controller127may comprise a processor. In various embodiments, controller127may be implemented in a single processor. In various embodiments, controller127may be implemented as and may include one or more processors and/or one or more tangible, non-transitory memories and be capable of implementing logic. Each processor can be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. Controller127may comprise a processor configured to implement various logical operations in response to execution of instructions, for example, instructions stored on a non-transitory, tangible, computer-readable medium configured to communicate with controller127.

System program instructions and/or controller instructions may be loaded onto a non-transitory, tangible computer-readable medium having instructions stored thereon that, in response to execution by a controller, cause the controller to perform various operations. The term “non-transitory” is to be understood to remove only propagating transitory signals per se from the claim scope and does not relinquish rights to all standard computer-readable media that are not only propagating transitory signals per se. Stated another way, the meaning of the term “non-transitory computer-readable medium” and “non-transitory computer-readable storage medium” should be construed to exclude only those types of transitory computer-readable media which were found in In Re Nuijten to fall outside the scope of patentable subject matter under 35 U.S.C. § 101.

In various embodiments and with additional reference toFIG.7, a method700of deicing is illustrated. The controller127may receive an activate command from the control interface175. Controller127may pass the activate command to the ice protection logic204. In response to the activate command, the ice protection logic204may command a source of compressed gas206to supply a compressed gas to one or more sets of tubes of anti-icing system400. In this regard, controller127may provide a compressed gas to a deicing boot of anti-icing system400such as deicing boot402, for example, by commanding the source of compressed gas to supply the compressed gas to the deicing boot. Controller127may receive an enable command from the control interface175(step702). In response to the enable command, controller127may poll sensors202for sensor data (step704). In response to polling sensors202, controller127may receive sensor data including an air temperature data and a liquid water content data (step706). Controller may pass the air temperature data and the liquid water content data to the ice protection logic204(step708). The ice protection logic204may determine, based on the air temperature data and the liquid water content data, an icing condition of the aircraft (step710). In response to determining the icing condition of the aircraft, the ice protection logic204may command the source of compressed gas206to supply the compressed gas to one or more sets of tubes of anti-icing system400(step712). In this regard, controller127may provide a compressed gas to a deicing boot of anti-icing system400such as deicing boot402in response to an icing condition. In various embodiments, the ice protection logic204may be configured to alternate fluid communication with the supply of compressed gas between the first set406of tubes and the second set408of tubes in response to a time signal. For example, the controller127may be configured to control a valve in fluid communication between the source of compressed gas206and the tubes404. In this way, controller may modulate the inflation of the first set406of tubes404and the second set408of tubes404in response to the icing condition of the aircraft.