Patent Application
20100300660
The invention relates to systems and methods for delivering gaseous heat carriers for de-icing, melting, and thawing surfaces, and more particularly to a Delivery Head System for optimizing heat transfer to a contaminated surface.
The removal of contaminant such as snow, frost, slush and ice on a surface is desirable in many industries. In the airline industry, the presence of contaminants is particularly considered a serious threat since it can affect an aircraft's aerodynamic integrity. A contaminated surface of an aircraft's wings may interfere with the smooth flow of air, thereby greatly degrading the ability of the wing to generate lift and cause catastrophic consequences. For these reasons, the airline industry regulations dictate that aircrafts are restricted from taking off if any form of contamination is adhering to the critical surfaces of an aircraft.
Conventional methods of de-icing aircrafts have typically consisted of spaying Large quantities of hot glycol based de-icing fluids onto snow or ice covered wings, fuselage, and blades. The most common method of spaying these fluids is the use of spray nozzles similar to those used by firefighters. This de-icing process thermally removes the ice, snow, and/or frost by the melting action of the de-icing fluid and by the hydrodynamic sweeping action of the de-icing fluid jet. During this type of de-icing process, a great deal of the heat content of the hot de-icing fluid is lost between the time it leave the spray nozzle and the time the fluid enters in contact with the targeted surface. As well, the distance between the nozzle and the targeted surface is often several meters. This factor, combined with winds and sub-zero temperatures results in significant heat losses and it inevitably contributes to a loss of the de-icing fluid to the surrounding atmosphere. This adds significantly to the heat energy required to remove the contaminating ice or snow. Where ice or snow contamination is significant large quantities of glycol are required. Since glycol-based fluids are expensive and environmentally hazardous, conventional methods of de-icing aircrafts create significant economic and waste management issues.
The conventional method of de-icing aircrafts using hot liquid, such as the heated glycol based fluids, is not the only method to transfer heat to a surface. Heat can also be transferred by radiation (normally infrared), by the application of a hot gas (most commonly air) and by the application of a gas that will experience a phase change in cooling.
More recently, moisture-laden air has been introduced as a heat carrying medium for the purposes of de-icing, snow melting, and thawing surfaces such as aircrafts, helicopter blades, walkways, driveways and constructions sites. Moisture-laden air transmits its heat energy, in part through phase change of its water content and in part by the cooling of the air and water vapour. The use of hot air, moisture-laden air and steam for de-icing, melting, and thawing surfaces eliminates the use of these expensive and environmentally hazardous glycol based de-icing fluids.
Canadian Patent Application No. 2,487,890 discloses inflatable delivery heads as a means of delivering moisture-laden air to a surface. These delivery heads placed in proximity to a surface transfers heat from the moisture-laden air to the surface, however, a portion of the heat is lost to the surrounding environment using current delivery heads.
There is a need for systems and methods for optimizing the transfer of heat from a gaseous heat carrier to a surface.
There is also a need for a Retraction-Deployment System in order to facilitate the storage and transport of a delivery head's inflatable chamber.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the invention.
The invention provides a Delivery Head System designed to optimize the heat transfer from a heat carrier, especially a Gaseous Heat Carrier, to a contaminated surface. The Delivery Head System comprises: a Delivery Head designed for containing the Gaseous Heat in proximity to a surface to be de-contaminated. The Delivery Head comprises an inflatable chamber designed to efficiently receive and deliver an effective amount of Gaseous Heat to a surface. In order to retain the Gaseous Heat in proximity to the surface, the Delivery Head is operatively coupled with a Containment Boundary or functional engages the surface to act as a Containment Boundary. The Delivery Head System further comprises an Inflatable Chamber Support System and Coupling Means for coupling the inflatable chamber to a conduit in communication with a source of gaseous heat. The Delivery Head System optionally comprises a Retraction/Deployment System with means for selectively retracting and deploying a Delivery Head's inflatable chamber in addition to a storage compartment for the inflatable chamber. The Delivery Head System may further comprise a Control System to manage the processes entailed in delivering a Gaseous Heat carrier to a surface.
One object of the invention is to provide a Delivery Head System for optimizing heat transfer to a contaminated surface.
In accordance with an aspect of the invention, there is provided a Delivery Head System adapted to deliver a gaseous heat carrier to a surface comprising a delivery head, the delivery head comprising an inflatable chamber adapted to receive a gaseous heat carrier and disperse the gaseous heat carrier to a surface; a support structure operatively connected to the inflatable chamber; means of coupling the inflatable chamber to a source of gaseous heat carrier; and a Containment Boundary operatively coupled to the said inflatable chamber.
In accordance with another aspect of the invention, there is provided a delivery head for delivering a gaseous heat carrier to a surface, the delivery head comprising: an inflatable chamber adapted to receive a gaseous heat carrier and disperse said gaseous heat carrier to a surface, the outer perimeter of said inflatable chamber extending downwardly; a delivery head support structure; and means of coupling a duct adapted to provide the forced gaseous heat carrier to said support structure and inflatable chamber.
In accordance with another aspect of the invention, there is provided a retraction/deployment system for selectively retracting and deploying a deliver head's inflatable chamber, the retraction/deployment system comprising a storage compartment and retraction/deployment means.
The term “contaminant” is used to define a deposit such as, for example, water, slush, snow, ice, hail, onto a surface,
The term “contaminated surface” is used to define any surface that comprises deposits of contaminant.
The term “gaseous heat carrier” is used to define any heat carriers that are in gaseous form, such as plain air, moisture-laden air, steam and the like.
The term “leading edge” is used to define the portion of a surface which functions to meet and break an air stream impinging thereon. Examples of leading edges would be forward edge portions of wings, stabilizers, struts, and other structural elements of marine vessels, towers and buildings.
The term “delivery head” is used generally to define the entire mechanism connected to the heat source that delivers the gaseous heat carrier to a surface.
As used herein, the term “about” refers to a +/−10% variation from the nominal value. It is to be understood that such a variation is always included in any given value provided herein, whether or not it is specifically referred to. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
The Delivery Head System is designed to optimize the heat transfer from a Gaseous Heat Carrier to a contaminated surface. The Delivery Head System comprises: a Delivery Head designed for containing the Gaseous Heat in proximity to the surface to be de-contaminated. The Delivery Head comprises an inflatable chamber designed to efficiently receive and deliver an effective amount of Gaseous Heat to a surface. In order to retain the Gaseous Heat in proximity to the surface, the Delivery Head is operatively coupled with a Containment Boundary or functional engages the surface to act as a Containment Boundary. The Delivery Head System further comprises an inflatable chamber support and coupling means for coupling the inflatable head to a source of gaseous heat. The Delivery Head System optionally comprises a Retraction/Deployment System with means for selectively retracting and deploying an inflatable chamber of a Delivery Head. The Delivery Head System may further comprise a Control System to manage the processes entailed in delivering a Gaseous Heat carrier to a contaminated surface.
Referring to
In one embodiment, the gaseous heat carrier is plain air. In one embodiment, the gaseous heat carrier is moisture-laden air. In one embodiment, the gaseous heat carrier is moisture-laden air and plain air. In such embodiments, the moisture-laden air and plain air may be used in distinct regions of the contaminated surface depending on the level of contamination in these regions or the moisture-laden air and plain air may be used at different times during the decontamination process.
In one embodiment, moisture-laden air and plain air are used sequentially such that the moisture-laden air removes the majority of contamination while the plain air dries the treated surface.
In one embodiment, the delivery head further comprises a means for delivery anti-freeze or anti-icing chemicals.
The Delivery Head System comprises at least one inflatable chamber adapted to receive and disperse the gaseous heat carrier to the contaminated surface, a Containment Boundary or Containment Boundary in effective proximity to the surface to be treated operatively connected to or integral with the at least one inflatable chamber and a support structure for supporting the inflatable chamber and optionally for connecting the Delivery Head to a delivery arm or the like. In some embodiments, the inflatable chamber being of appropriate size and shape functions as the Containment Boundary when appropriately positioned. Optionally, the delivery system may further comprise a Retraction/Deployment System for selectively retracting and deploying the delivery head's inflatable chamber and/or Control System.
The Delivery Head System may be designed for a specific application. For example, the Delivery Head System may be specifically adapted for the de-icing of both aircraft critical and non-critical surfaces. As such, the Delivery Head System may comprise a Delivery Head having an inflatable chamber specifically contoured to the shape of an aircraft wing, specifically shaped to de-ice helicopter rotor blades, aircraft propellers or aircraft engines, engine inlets, a helicopter “hell hole” (the open area below the transmission) or other open spaces. Alternatively, the inflatable chamber may be specifically contoured to the shape of an aircraft tail or the horizontal stabilizers of an aircraft.
Other applications in which the Delivery Head System may be specifically adapted include marine de-icing. For example, the Delivery Head System may be specifically adapted for the de-icing of marine vessel structures including the deck, handrails, ladders, etc. The system may be adapted to de-ice rail tracks. In addition, the Delivery Head System may be adapted for the de-icing of structures that are sensitive to traditional de-icing chemicals or structures in environments sensitive to traditional de-icing chemicals.
To facilitate the removal of contaminants from a surface, the Delivery Head further comprises a containment boundary. In some embodiments, for example in embodiments specifically designed to de-ice aircraft engines or helicopter “hell holes”, the inflatable chamber being of appropriate size and shape functions as the Containment Boundary when appropriately positioned. In addition to facilitating the removal of contaminants, the Containment Boundary reduces the amount of gaseous heal carrier necessary to decontaminate a surface and/or reduces the requisite decontamination time and/or reduces or eliminates the requirement to use moisture laden air.
Referring now to
The Delivery Head System may further comprise a Retraction/Deployment System for selectively retracting and deploying the inflatable chamber of the Delivery Head. The Delivery Head System may further comprise a Control System and may be designed for integration into a larger de-icing system that comprises various positioning, sensing and/or control components.
The Delivery Head 5 of the system is designed to deliver heat to a contaminated surface and contain the heat in proximity to the surface. Accordingly, the Delivery Head is adapted to receive a gaseous heat carrier 80 that is generated and pressurized in a heat source. During operation, the gaseous heat carrier 80 flows through one or more ducts or conduits 50 to the delivery head, which is positioned in proximity to the contaminated surface. The Delivery Head 5 is coupled to the source of gaseous heat carrier by coupling means 25. To facilitate decontamination of a surface, the Delivery Head further comprises a Containment Boundary 80 in close proximity to the surface to be treated or containment boundary. In some embodiments, the inflatable chamber being of appropriate size and shape functions as the Containment Boundary when appropriately positioned.
The Delivery Head 5 comprises an inflatable chamber 10 having an interior space defined by an enclosing surface or walls. The enclosing surface or walls can be configured in any three-dimensional shape including spheres, boxes, cones, pyramids, cubes, etc. The enclosing surface or walls have at least one region with one or more holes to allow the gaseous heat carrier to enter the inflatable chamber and a plurality of perforations, and/or microperforations and/or pores and/or gas permeable area that directs the pressurized gaseous heat carrier onto the contaminated surface.
The inflatable structure can be fabricated to the specific requirements of one or more surface(s) and/or structures to be decontaminated. The inflatable chamber can be constructed in a variety of shapes, sizes, and configurations to conform to different types of contaminated surfaces and thereby promote heat transfer from the stream of gaseous heat carrier to the surface in question. A worker skilled in the art would appreciate that a wide variety of different shapes and configurations of inflatable chambers are possible without departing from the scope of the invention.
In one embodiment, a flat, generally mattress-shaped inflatable chamber is provided to increase the surface area being treated. Such a design would be appropriate for treating flat surfaces such as, for example, pavement or the decks of marine vessels and the like. In one embodiment of the invention, to better accommodate the form of an aircraft wing, for example, the Delivery Head can shaped so as to more closely fit the curved shape of an aircraft wing, In one embodiment, the inflatable chamber is the same size and shape of an airplane wing. In one embodiment, the inflatable chamber is round or circular shaped so as to be able to cover the intake of an airplane engine. In one embodiment, the inflatable chamber is L-shaped or C-shaped so as to be able to cover the leading edge of an aircraft wing.
Referring to
Referring to
In one embodiment, the inflatable chamber comprises internal walls that divide the chamber into one or more sub-chambers or the Delivery Head may comprise two or more operatively connected inflatable chambers. Such embodiments may be specifically adapted to decontaminate multi-surface structures such as aircraft tail sections or wing surface and leading edge. Optionally, such systems may be designed such that only the chambers that are required for a specific treatment are deployed. For example, for removal of frost contamination of the wing it may only be necessary to deploy the section which covers the leading edge of the wing while for heavier contamination it may be necessary to deploy the sections that cover both the leading edge of the wing and the surface of the wing. Optionally, the portion that is not deployed during specific applications may be retracted or contained.
With reference to
In one embodiment, the sub-chambers are defined by internal walls and are not visible from outside the inflatable chamber.
In one embodiment, each sub-chamber 110 can have a separate coupling means 25 that connects it to the air duct 50. In one embodiment, the flow of gaseous heat carrier into each sub-chamber 110 can be controlled separately. A worker skilled in the art will be aware of the necessary control mechanisms necessary to exercise controls over the flow of gaseous heat carrier into each sub-chamber. In one embodiment, the sub-chambers 110 are interconnected and the inflatable chamber has a single coupling means. Optionally, the sub-chambers are interconnected by a pressure valve. As delivery heads and, in particular, the inflatable chamber, may be built in a wide variety of shapes and sizes, the range of possible forms that may be used to deliver the gaseous heat carrier is almost unlimited. The gaseous heat carrier output from the Delivery Head may vary over a wide range, from a few hundreds of cubic feet per minute, (CFM), to many thousands of CFM, depending on the type of application and desired capacity of the system. The internal pressure of in the inflatable chamber may likewise vary widely from 0.2 inch water column, (0.2″ wc), to more than one pound per square inch, (i.e. 27″ wc). Designing for higher internal pressure provides for a more firm and more easily managed Delivery Head but extracts a penalty in terms of power requirements of the blower system.
In one embodiment of the delivery head, pressures ranging from 0.5 to 10 inches water column can be used, but a higher or a lower pressure could be used to suit a particular requirement.
In order to facilitate decontamination of the surface, the Delivery Head is designed to promote the retention of a gaseous heat carrier proximate to the contaminated surface. The Delivery Head includes a Containment Boundary in close proximity to the surface to be treated operatively connected to or integral to the at least one inflatable chamber and a support structure for supporting the inflatable chamber and optionally for connecting the Delivery Head to a delivery arm or the like. In some embodiments, the inflatable chamber being of appropriate size and shape functions as the Containment Boundary when appropriately positioned. Containment Boundary can include flaps, skirts, curtains, fringe, sealing elements and the like.
Such Containment Boundary can be integral to the inflatable chamber or reversibly coupled to the inflatable chamber such that Containment Boundary can be interchanged or replaced. The Containment Boundary can optionally be made in sections with individually sections being removable and/or replaceable. The Containment Boundary can be manufactured of similar material as the inflatable chamber and optionally may be inflatable and insulated. In some embodiments, the Containment Boundary is an extension of the inflatable chamber. In some embodiments, the Containment Boundary contains support elements or stiffeners. Optionally, the Containment Boundary is weighted. Accordingly, one or more weights may be provided and at any desired location but preferably near or at the bottom of the means for containing the gaseous heat carrier.
Alternatively, the inflatable chamber may be the means for containing the gaseous heat carrier. For example, the inflatable chamber may be sized and shaped to function as a cap for open spaces or engines.
In one embodiment, a skirt extends peripherally around the inflatable chamber in order to reduce heat losses that occur in the presence of wind and extremely cold weather. It can be made of insulated material to increase the heat retention from the gaseous heat carrier travelling between the target surface and the bottom surface of the inflatable structure. The skirt is operatively coupled to the inflatable chamber and extends downwardly perpendicular to the target surface. The skirt creates a partial enclosure shielding the area between the inflatable chamber and the target surface from wind and helps retain heat within the partial enclosure.
Having further regard to
In order to reduce heat losses that occur in the presence of wind and extremely cold weather, containing means 30 extend peripherally around the inflatable chamber 10. The containing means can be formed from a flexible and resilient material, cloth, rubber, plastic, nylon, or other materials known to one of ordinary skill in the art. It can be made of insulated material to increase the heat retention from the gaseous heat carrier 80 travelling between the target surface and the bottom surface of the inflatable structure. The containment means 30 is operatively coupled to the inflatable chamber 10 and extends downwardly and perpendicular to the target surface. The containment means 30 shields the area between the inflatable chamber 10 and the target surface from the wind and to help retain heat within the temporary enclosure.
In one embodiment of the invention, in order to reduce heat losses that occurs to the surrounding environment, the outer perimeter of the inflatable chamber extends downwardly towards and substantially perpendicular to the target surface. This creates a partial enclosure between the inflatable chamber and the target surface shielding the area from wind. This would also help retain the heat within the partial enclosure.
Referring now to
A duct 50 adapted to provide a forced gaseous heat carrier 80 to the inflatable chamber 110 is operatively coupled to the support structure 20 by coupling means 25. The inflatable chamber 110 being operatively coupled to the support structure 20 forming a substantially air tight seal between the duct 50 the inflatable chamber 110.
The inflatable chamber 110 comprises a bottom surface 14 and a top surface 13 sealed together at the periphery defining a chamber. The inflatable chamber can be made of flexible material whereby the inflatable chamber 110 may be folded to a compact condition when deflated. The top surface 14 comprises one or more perforations 75 to allow the gaseous heat carrier 80 to enter the inflatable chamber 110 where the top surface meets the inflatable chamber 110. The bottom surface 14 comprises a plurality of perforations 70 for allowing the gaseous heat carrier 80 to escape the chamber and come into contact with the contaminated surface 90.
The forced gaseous heat carrier 80 enters through holes 75 of the top surface 13, such that there minimal variation in the pressure at the duct 50 and the inflatable chamber 110. The air supply blower (not shown) and the size of the perforations 70 of the bottom surface 14 of the inflatable chamber 110 are selected such that the internal pressure inside the inflatable chamber 110 gives the inflatable chamber 110 its substantive form and firmness. The size and number of perforations 70 can be selected to achieve a desired pressure within the inflatable chamber 110. Pressure will also determine the velocity at which the gaseous heat carrier 80 exits the perforations 70 of the bottom surface 14 and the rate of gaseous heat carrier circulation over the contaminated target surface 90.
In order to increase the heat transferred from the gaseous heat carrier to the contaminants on a surface, the perimeter edge of the inflatable chamber 110 extends downwardly towards the target surface creating a partial enclosure between bottom surface 14 of the inflatable chamber 110 and the target surface 90. The partial enclosure created allows the gaseous heat carrier 80 exciting the perforations 70 to be contained and protected from the surrounding environment. In this embodiment, the shape of the inflatable chamber creates the gaseous heat carrier containment means, A great amount of heat from the gaseous heat carrier 80 can therefore be transferred to the contaminated surface.
In one embodiment of the invention, in order to reduce heat loss that occurs to the surrounding environment, the inflatable chamber is shaped to form the target surface increasing the length of time the gaseous heat carrier is in contact with the target surface. In one embodiment of the invention, the outer perimeter of the inflatable chamber extends downwardly towards the target surface forming a box-like structure. In one embodiment of the invention, the outer perimeter of the inflatable chamber extends curves downwardly towards the target surface.
Referring now to
The Delivery Head may be built in a wide variety of shapes in order to increase the heat transferred from the gaseous heat carrier to the contaminants on a surface. In one embodiment of the invention, the inflatable chamber has a ball shape. In another embodiment of the invention, the inflatable chamber has a cylindrical shape.
The material for the wall(s) of the inflatable chamber and/or the containment boundary can be formed from flexible, resilient materials, such as polyvinyl chloride sheeting (PVC), cloth, rubber, plastic, nylon, or other materials known to one of ordinary skill in the art or combination thereof. In embodiments in which more rigidity to the inflatable chamber is desired, the inflatable structure can be constructed in part or wholly from drop-stitch fabric. The material in one or more regions of the inflatable chamber has a plurality of perforations and/or microperforations and pores and is gas permeable. The edges of mating surfaces and walls can be fused using such process as radio frequency (RF) welding, ultrasonic welding, heat welding, or other process known to one of ordinary skill in the art. In addition, the connection of the network of tethers to the desired locations of the inflatable chamber in order to define locations of indentation formation can be performed in a similar manner. Alternately, depending on the material used for fabrication of the delivery head, a mechanical coupling technique, for example, sewing can be used for connection of one or more of the surfaces, walls, or ends to one another, and in addition to the coupling of the tethers to the device. It would be understood, that as the act of sewing can result in punctures within the material, a further sealing compound can be required in order to seal this connection to inhibit pressure loss at these connection sites.
In one embodiment, in order to avoid loss of heat of the gaseous heat carrier in the inflatable chamber to the cold surrounding environment the inflatable chamber can be fully or partially lined with insulating material or fully or partially fabricated there from. The forced gaseous heat carrier enters through one or more inputs, such that there minimal pressure variation between the air duct and the inflatable chamber. The air supply blower and the size of the perforations in the lower surface of the inflatable chamber are selected such that the internal pressure inside the Delivery Head gives the inflatable chamber substantive form and firmness. The size and number of perforations can be selected to achieve a desired pressure of gaseous heat carrier. Pressure will also determine the velocity at which the gaseous heat carrier exits the perforations and the rate of gaseous heat carrier circulation over the contaminated surface.
The material used for the top and bottom surfaces, and side walls can be a substantially inelastic material, which is substantially impervious to air penetration. While the material is substantially inelastic, the material is configured to be capable of a predetermined amount of elastic deformation during use and operation of the delivery head.
In one embodiment of the invention, as the bottom surface of the inflatable chamber will be in close proximity to the fans of an airplane engine, this bottom surface can be configured to have a predetermined resistance to tearing or other failure of the material. For example, the bottom surface can be designed having a thickness greater than other portions of the delivery head, in order to account for the potential of additional wear and abrasion on the bottom surface. In one embodiment of the invention, it will be desirable to minimize the risk of damage to the contaminated surface from contact of the delivery head. As a result the bottom surface of the Delivery Head can be made of fabric material to prevent the risk of scratching.
Having further regard to
When the gaseous heat carrier exits the inflatable chamber and strikes the target surface, a portion of the gaseous heat carrier's heat content would be transferred before the gaseous heat carrier bounces off the contaminated surface and creates active circulation of the gaseous heat carrier between the contaminated surface and the bottom surface of the inflatable chamber. The active circulation of the gaseous heat carrier in proximity to the contaminated surface creates a gaseous film over the surface transferring additional heat to the surface. After circulating along the contaminated surface, the cooled gaseous heat carrier exits along the distal edges of the surface.
In order for an efficient transfer heat to occur between the gaseous heat carrier and the cooler contaminated surface there must be intimate contact between the two. The extent of the contact can be improved by extending the retention time, or the length of time that the gaseous heat carrier is placed in close proximity to the contaminated surface, and by ensuring circulation of the gaseous heat carrier over the surface. A worker skilled in the art will appreciate that maximizing this retention time will be a factor in the design of the delivery head. This extended retention time is more easily achieved when a relative large area of contaminated surface can be treated at a one time. This also reduces the need for repeated re-positioning of the delivery head. For example, in relation to aircraft, treating a large area of an aircraft wing at one time, or even the entire wing of a small aircraft in one operation, is more efficient in terms of heat transfer than doing smaller areas with more heat intensity. The size and distribution of the egress holes will vary depending upon application. The size and distribution of the egress holes may be uniform over the entire surface or region or may vary. The position and size of egress holes may be specifically adapted to apply large quantity of gaseous heat carrier to areas which generally have higher levels of contamination. For vertical surfaces, for example engines inlets and aircraft tail sections; it is desirable to have more heat supplied in the lower region to compensate for the rapid rise of the gaseous heat carrier. Heat egress holes may be located at side as well as bottom to reach edges or the like.
In one embodiment of the invention, the surface of the Delivery Head that is in proximity to the contaminated surface is made wholly or partly of a gas permeable material.
The inflatable chamber may optionally comprise an internal support system. Internal support systems for inflatable structures are known in the art include tethers, baffles, bulkhead, internal support beams or an endoskeleton. The inflatable chambers may optionally be of I-beam or drop-stitch construction.
With reference to
With reference to
The term, tether, refers to a means of connection between the top and bottom walls within the defined perimeter. The effect of a network of tethers on the chamber causes the two surfaces to form an array of uniform or non-uniform indentations upon inflation.
This system of indentations provides additional stability to the Delivery Head when inflated. In one embodiment, a tether is formed from a substantially inelastic but flexible material which enables the generation of a tensile force therein with minimal elongation. In one embodiment, a tether is formed from a flexible, substantially elastic material.
Indentation configuration can be controlled by the tether location relative to other indentations as indentation geometry and boundaries are affected by the local topography and surface tension of the bottom surface which can be created by adjacent indentations.
In addition, indentation configuration can be controlled by tether length, which can affect the depth of an indentation as well as the interrelation of adjacent indentations. For example, when a short tether is positioned relatively close to a longer tether, the indentation generated by the short tether can be deeper than that created by the longer tether. This difference in depth of an indentation can result in a difference in the volume defined by an indentation and a difference in the area of the support surface in contact with the indentation, which can result in differing pressure in escaping gas from different indentations.
The geometry of a tether upon attachment to the top surface and bottom surface of the inflatable chamber can take a number of geometric shapes. In one embodiment a tether is configured as closed geometric shapes which form hollow structures having cross sectional shapes including round, oval, diamond, square, rectangular or any other desired cross sectional shape. These hollow shaped tethers can further have varying cross sections over their height, for example they can be configured as cones, pyramids, frustums or other shapes as would be known to a worker skilled in the art. In addition, the tethers may be sized and placed to form curved structures, C-shaped structures or the like as is known in the art.
In one embodiment of the invention, a tether is configured as an open geometric shape, for example a strip, loop, or other open geometric shape as would be readily understood.
In order to perform its function efficiently, the Delivery Head must be able to maintain a consistent shape. It is also necessary to provide a platform on which to connect the Delivery Head to the heat source and positioning and transport means which will prevent the Delivery Head from being detached. This is especially the case when the Delivery Head is being used during periods of inclement weather where high wind speeds could cause the Delivery Head to deform or separate from the air duct and positioning and transport means. While the indentation and tether system discussed above contributes to the stability of the delivery head, additional support means can be desirable.
According to one embodiment, the support means comprises a backing material attached to the top surface of the inflatable chamber. The material for the backing material can be constructed of a rigid material sufficient to provide the necessary stability to the Delivery Head such as wood, metal, plastic, synthetic board and others. Disposed towards the center of the backing material is located one or more holes that correspond with the holes in the top surface to allow gaseous heat carrier to flow from the heat source into the inflatable chamber. According to one embodiment, the holes in the backing material and upper surface each correspond to a separate chamber within the delivery head.
In order to facilitate the connection of the Delivery Head to a positioning and transport system as well as the heat source, a coupling means is provided for removably attaching the air duct to the delivery head. The air duct can be attached at any appropriate position. Appropriate position can, in part, be determined by the specific application. According to one embodiment, the coupling means comprises a mounting plate capable of being removably attached to the backing material such that, when attached it forms a seal that is generally air resistant. Various methods of attachment of the mounting plate to the backing material would be well known to a worker skilled in the art and could include for example, a slot and tab system, latches, or magnets. According to one embodiment, the mounting plate comprises a rubber or latex coating to assist in generating a seal against the backing material. The mounting plate comprises one or more holes that generally correspond with the holes in the top surface and the backing material to allow gaseous heat carrier to flow from the heat source into the chamber of the delivery head.
The mounting plate also comprises one or more generally conical ducts wherein the wider end of the cone is located over one or more of the holes in the mounting plate and sealingly affixed to the surface of the mounting plate such that it forms a generally air tight seal. The conical duct is designed such that the narrower end of the cone can be sealingly attached to an air duct leading to the heat source. The various means by which the narrow end of the cone could be sealingly attached to the air duct would be well known to a worker skilled in the art and could include for example, a gasket system, elastic or compressible cuffs, or the like. According to one embodiment, the narrower end of the cone is permanently sealed to the end of the air duct. The material for the conical duct can be constructed of a flexible or semi-rigid resilient material such as polyvinyl chloride sheeting (PVC), thermoplastic impregnated cloth, plastic, nylon, rubber or other materials known to one of ordinary skill in the art.
According to one embodiment, the backing material is formed of interconnected tubing such as aluminum or rigid plastic tubing and the mounting plate is removably connected directly to the top surface of the delivery head.
In one embodiment, the Delivery Head frame (support) may be coupled separately from the inflatable chamber.
Using large delivery heads may decrease the time to decontaminate a target surface. For example, in the airline industry, it may be favorable for the Delivery Head to be the size and/or shape of the wing in order to de-ice the surface in one pass. The potential disadvantage of using large delivery heads is that more difficult to handle particularly in windy condition. In the case of aircraft de-icing, mobile de-icing units must travel to different areas over the air field on order to decontaminate an aircraft. Large inflatable delivery heads for aircrafts measuring several meters in length and width could potentially be difficult to handle.
To mitigate the susceptibility to wind conditions, according to one embodiment of the invention, Retraction/Deployment System is used to more readily manage the transportation of delivery heads.
Three different approaches are described for deploying and retracting delivery heads, including the use of suction, mechanical retraction and elasticity. A worker skilled in the art will be aware of the Retraction/Deployment Systems can be used to retract and deploy the inflatable chamber without departing from the scope of the invention.
Referring now to
In one embodiment, the sensor system could detect the stability of the inflatable chamber 210. The sensor system could also detect changing wind conditions and alert the system to retract prior to a set of predetermined conditions.
The negative air pressure 630 passes through said duct 610 and storage compartment 600, removes the air in inflatable chamber 10 and retracts the inflatable chamber 10 depleted of air into the storage compartment. The stowed inflatable chamber 10 can easily be transported from one location to another.
Referring now to
The webbing 660 is preferably made of a material with a low friction coefficient. In one embodiment, the webbing is made of low friction straps. The webbing could also be cable, ropes, bungee cord or the like, whether or not such line has a low friction coefficient or is stretchable. In one embodiment, the webbing 660 comprises a plurality of straps coupled to the inflatable chamber 10. In one embodiment, the webbing 660 comprises a wire or cable netting surrounding the inflatable chamber 10, In one embodiment, the webbing 660 is comprised of a plurality of straps coupled to the inflatable chamber 10. Pluralities of roller assembly 670, which carry and enable the movement of the low friction webbing, are coupled to the storage compartment 650. The roller assembly 670 provide a means for deploying or retracting the webbing 660. In one embodiment, the roller assembly is spring loaded so as to retract the inflatable chamber when the air pressure is released. In one embodiment, the roller assembly is motorized.
In one embodiment, the roller assembly 670 are cylindrical in shape and are capable of rotation about their central axis. A worker skilled in the art will be aware of the variety of roller assembly can be used without departing from the scope of the invention. In one embodiment, a pull cable system is used instead of the roller assembly. In one embodiment, associated with the roller assembly is a tensioning means, in order to ensure the webbing remains taut and in adequate contact with the roller assembly.
In one embodiment, guiding means 680 are strategically coupled to the storage compartment 650. The guiding means can be used to guide the movement of the webbing 660 along its path of travel. The guide means may assist the reduction of the binding of the webbing during retraction or deployment of the inflatable chamber 10.
In order to retract a deployed inflatable chamber 10 the roller assembly 670 is engaged forcing the webbing 660 to be wound onto the spool of the roller assembly 670, until the inflatable chamber is stowed in the storage compartment 650. The storage containment 650 containing the inflatable chamber 10 may be detached for storage. It may be replaced with another storage containment with an inflatable chamber of a different purpose. Retraction of the inflatable chamber can be accomplished manually or automatically. Automatic activation may be accomplished using a sensor system to detect the position of the delivery head.
Referring now to
In order to retract a deployed inflatable chamber 10 the positive air pressure being applied in a Delivery Head is shut off causing the elastic web 700 under tension to retract compressing the inflatable chamber 10 onto itself to a fraction of its inflated dimension.
Referring now to
Referring to
The Delivery Head comprises an optional Control System that monitors and adjusts the various conditions and or parameters within the inflatable chamber of the Delivery Head and/or monitors and/or deployment and retraction of the inflatable chamber. The Control System comprises one or more sensing elements for monitoring and obtaining data regarding operating parameters within the system, and one or more response elements for adjusting operating conditions within the system. The sensing elements and the response elements are integrated within the system, and the response elements adjust the operating conditions within the system according to data obtained from the sensing elements. The Control System provides for active control of the Delivery Head internal pressure, temperature, egress rate, relative humidity, inflation level and condensation within the delivery head.
In one embodiment of the invention, the system comprises sensing means to receive and interpret information regarding the functioning of the system and adjust accordingly. The components of the system will be described in greater detail below.
A variety of systems are known in the art for generating and/or containing gaseous heat carrier.
Systems for producing moisture-laden air include systems which utilize hot water spray; a hot water wet-coil; a method wherein water is sprayed into high temperature blown air; or a steam-based method, among other systems. Detailed descriptions of these systems for generating moisture-laden air is found in Canadian Patent Application 2,487,890.
Systems for producing hot air are known in the art and include heater and blower systems. Appropriate are known in the air and can include combustion heaters or instant heaters that rapidly transfer heat to the air. In one embodiment, hot air is produced by passing ambient air thru one or more heated coils.
In order to enable the Delivery Head to be positioned in relation to a number of different contaminated surfaces, the heat source is operatively connected to the Delivery Head by means of one or more air ducts adapted to provide a forced gaseous heat carrier to the delivery head. According to one embodiment, the air duct can be insulated to avoid heat loss from the gaseous heat carrier travelling along the duct to the surface of the duct.
According to one embodiment, the ducts are flexible. According to one embodiment, the one or more flexible air ducts comprise one or more insulated tubes similar to those commonly found in heating and ventilation systems. The construction and composition of such flexible insulated tubes will be well known to one of ordinary skill in the art.
The delivery system provides for the efficient decontamination of a surface by directing and containing heat in proximity to the surface. Prior to commencing the decontamination an assessment of contamination levels on the surface may be made manually (including by visual inspection) or in an automatic or automated manner, for example, by using appropriate sensors. Sensing of contamination levels may be remote or other. Following a determination of contamination levels and/or an assessment of environmental conditions, an appropriate gaseous heat carrier may be chosen. The Delivery Head is positioned in proximity to the surface to be treated and gaseous heat carrier is delivered to the surface thereby melting the contaminating frost, ice and/or snow. If moisture-laden air is used as the gaseous heat carrier, and if necessary, the surface may be dried by the directed application of heated air through the delivery head. Optionally, the decontaminated surface may be treated with a light spray of de-icing or anti-icing chemicals to provide enhanced residual protection.
Positioning of the Delivery Head may be facilitated by a positioning system that determines the position and/or orientation of the delivery head. The position may be determined relative to the surface to be decontaminated by the use of proximity and/or position sensors.
Optionally, the inflatable Delivery Head may be deployed after the Delivery Head is substantially in position. After deployment, the positioning may further be refined.
The choice of gaseous heat carrier, in part, depends on the contamination level present on the surface to be decontaminated. Frost, light ice and light snow contamination can be effectively removed using heated air if the heat is retained in proximity to the surface. Using an appropriately designed delivery heads and heated air flow, the Delivery Head affects a heat transfer rate from dry air sufficient to remove frost or light accumulation of ice or snow at a rate that is acceptable for aircraft de-icing.
In one embodiment of the invention, a Delivery Head measuring 14 ft by 8 feet is used to remove frost or light ice cover over an aircraft surface. In this embodiment, an air temperature of 175° F. is used in conjunction with airflow of 6000 cfm. If outside temperature is at or near 0° F., the heat energy required to heat this air is about 1250,000 BTU/hr. Of this about 800,000 BTU is available for transfer to the surface (if the transfer was to be essentially complete, that is if the air was cooled to the temperature of melting ice or snow. This is of course not possible in practice but efficiencies of 50%, corresponding to the air being cooled from 175° F. to 100° F., are achievable. The result is approximately 400,000 BTU/hr delivered to melt the contaminating frost, ice and/or snow. This is sufficient to melt 40 lbs of ice per minute. Such output is more than adequate to remove frost from the aircraft surface and leave the surface at a temperature well above the freezing point.
To effect the timely removal of more significant levels of contamination, moisture laden air or the like or a combination of moisture laden air and dry air may be used. The rate of contaminant removal that can be achieved by a stream of air is proportional to the amount of heat that is carried by that air stream. This in turn depends in part upon the temperature of the air, but more importantly, it depends upon the water vapour content of the air. Air with a higher degree of humidity contains more heat than dry air (referring to
Lower concentrations of water vapour in air carry lower amounts of energy, but the amounts are still sufficient to efficiently melt ice and/or snow in a timely manner. In addition, by using moisture laden air with a lower relative humidity reduces water condensation in the system. Moisture laden air may be considered for in the context of this delivery system to be a mix of air and water vapor in which the air component is greater in mass then the water vapor component, but in which the available heat energy from the water vapor component, for purposes of de-icing surfaces or melting snow and ice, is greater by a factor of 2 or more than the available heat energy of the air component.
If the surface has significant accumulation of snow or ice moisture-laden air will melt it quickly and the water from the condensing moisture-laden air will run off the surface with the much larger volume of melt water. The surface will then be dried by a combination of the heat imparted to the surface from the moisture-laden air and in part by continuing to heat the surface with warm dry air.
In situations where there is insufficient frozen contaminant to produce run-off when melted, as in light frost conditions, it is often best to go directly to the dry air even though it is a less efficient heat transfer medium. Using moisture-laden air, will raise the surface temperature of the surface faster and that regard contribute the drying process, but on the other hand it will add to the water to be evaporated. The amount of frozen material on the surface, and the temperature of the surface itself will determine whether moisture-laden air or plain warm air with a Delivery Head is the most efficient and effective means to defrost.
The Delivery Head System may be integrated into a larger de-icing system which may include a positioning system for positioning and/or maintaining the position of the Delivery Head in proximity to the surface to be decontaminated. Such larger integrated de-icing systems may optionally further comprise a system for sensing and monitoring contamination levels. The sensing system may further comprise a display or indicator for indicating the contamination levels. Such an indicator may further comprise an indicator for indicating the appropriate choice of gaseous heat carrier based on the sensed characteristics.
In one embodiment, the sensing system assesses contamination levels prior to commencement of the decontamination process. In one embodiment, the sensing system assesses contamination levels during the decontamination process. Concurrent monitoring of contamination levels may be intermittent or continuous. In one embodiment, the system assesses contamination levels in real-time. Optionally, the sensing of contamination levels may be remote sensing. The sensing system optionally may be interactive with the Control System thereby facilitating the adaptive de-icing of the surface. The larger integrated de-icing systems may be integrated with traditional chemical de-icing facilities and thereby result in a reduction in the total glycol used.
In one embodiment, the decontamination of a surface is accomplished using the delivery system of the invention and the anti-icing of a surface is done using traditional chemical techniques.
The integrated de-icing systems may either be a mobile or fixed system. Accordingly, in one embodiment, the delivery system is a mobile unit. As a mobile unit, the delivery system may be manually propelled or motor driven or combination thereof. Referring to
Referring to
The integrated de-icing system may also comprise a Control System that monitors and adjusts the various operating parameters within the system. The Control System comprises one or more sensing elements for monitoring and obtaining data regarding operating parameters within the system, and one or more response elements for adjusting operating conditions within the system. The sensing elements and the response elements are integrated within the system, and the response elements adjust the operating conditions within the system according to data obtained from the sensing elements. The Control System provides for active control of the Delivery Head positioning means to ensure that the Delivery Head is positioned in close proximity to a surface without coming into contact with the surface. The Control System also provides for the monitoring of contamination levels on a surface, characteristics of the gaseous heat carrier and ambient conditions including temperature, pressure and relative humidity.
In one embodiment, the positioning of the Delivery Head in proximity to a surface is via a positioning means.
As the Delivery Head will need to be applied to a variety of contaminated surfaces, a positioning and transport means is necessary to bring the Delivery Head into engagement with and to maintain engagement with the surface to be treated. According to one embodiment, the positioning means is attached to the support means of the delivery head. According to one embodiment, the positioning means is attached to the coupling means.
With reference to
With reference to
According to one embodiment, the positioning system is attached to a vehicle such as an automobile, which also houses the heat source. This would enable the entire system to be mobile and thus more flexible. According to another embodiment, the heat source is attached to an interconnected series of pipes. When in use, the air duct is connected to an outlet of the series of pipes to provide gaseous heat carrier to the delivery head. Such a configuration would allow for a more lightweight Delivery Head system. According to one embodiment the heat source is stationary and the air duct is long and flexible enough to be transported with the delivery head.
In one embodiment of the invention, the positioning means are dynamically controlled, optionally in conjunction with a Control System that is designed to position the Delivery Head in close proximity to the surface to treated in order to maximize the transfer of heat from the gaseous heat carrier to the surface with the contaminants. According to one embodiment, the Control System is configured to adjust the position of the Delivery Head to keep it in close proximity to a surface without coming into contact with the surface.
The delivery optionally comprises a variety of sensing elements or sensors for monitoring contamination levels on the surface to be treated, position or orientation of the delivery head, characteristics of the gaseous heat carrier and/or ambient conditions include temperature, pressure and relative humidity. Sensing elements contemplated within the invention, as defined and described above, can include, but are not limited to, temperature sensing elements, position sensors, proximity sensors, orientation sensors and means for monitoring the gaseous heat carrier.
The term “sensing element” is used to describe any element of the system configured to sense a characteristic of a gaseous heat carrier production process and the target surface, wherein such characteristic may be represented by a characteristic value useable in monitoring, regulating and/or controlling one or more processes of the system. Sensing elements considered within the context of the process of making a gaseous heat carrier, delivering a gaseous heat carrier, determining the proximity of the target surface, determining the characteristics of the contaminants, monitoring the temperature of the target surface and the decontamination may include, but are not limited to, sensors, detectors, monitors, analyzers or any combination thereof for the sensing of process, weather, fluid and/or material temperature, pressure, flow, composition and/or other such characteristics, as well as material position and/or disposition at any given point within the system and any operating characteristic of any process device used within the system. It will be appreciated by the person of ordinary skill in the art that the above examples of sensing elements, though each relevant within the context of a de-icing system, may not be specifically relevant within the context of the present disclosure, and as such, elements identified herein as sensing elements should not be limited and/or inappropriately construed in light of these examples. In another context “sensing element” may mean a means of sensing the distance of the Delivery Head to the surface and provide feedback information that is used automatically or manually to position the Delivery Head in an optimum position and/or facilitate maintaining the Delivery Head in an optimum position.
Sensors for detecting and monitoring contamination levels are known in the art and include infra-red and near infra-red sensing technologies, reflective object sensors or switches; electro-optical sensors, acoustic sensors, radar sensors ultrasound sensors or laser detector systems or other system known to the worker skilled in the art. Commercially available ice detection systems include MDA's Ice Camera and Goodrich IceHawk®. The sensors may further measure the presence, composition, consistency and thickness of contaminants on a surface. In one embodiment, the system or sensors for detecting contamination including frost, ice or snow is disposed on the distal end of the boom. Optionally, the delivery end may be automatically positioned to areas of contamination by the Control System in response to singles from these sensors.
In one embodiment, the sensor for detecting and monitoring contamination levels is an infrared camera mount on the boon arm of the delivery system.
The delivery system may further comprise one or more position and/or proximity sensors for monitoring the position of the delivery system and its position relative to the surface to be treated. Appropriate proximity sensors are known in the art and include but is not limited to infrared proximity sensors, electromagnetic radiation proximity sensors, sonar, ultrasonic proximity sensors and laser proximity sensors. The proximity sensors may be place at various locations on the delivery system including but not limited to on the boom on inflatable chamber. The delivery system may further in a variety of probes which detect contact with the surface to be decontaminated. In one embodiment, the one or more probes extend from the surface of the inflatable bed proximal to the surface to be treated and signal when the probes contact the surface. The position of the delivery system relative to the surface to be decontaminated can be further monitored using GPS or radar or other means known in the art. The proximity and position sensors and probes may be used in conjunction with the Control System to optimize positioning of the delivery head. The position of the delivery system and, in particular, the position of the Delivery Head relative to the surface to be treated may be monitored visually using a camera mounted on the delivery system.
The Delivery Head may be equipped with a system of determine orientation of the delivery head. For example, the Delivery Head may be equipped with a gyroscope or other means of detecting orientation of the delivery head. In addition, the Delivery Head may be equipped with a system for maintaining orientation and positioning relative to the surface being treated.
The delivery system may be equipped with an array or system for detecting ambient conditions conducive to ice or frost formation. This array or system may include sensors for detecting or measuring static pressure, a total pressure, a total temperature, a dew point temperature, and liquid water content, and output a risk assessment for ice or frost formation based on the measured parameter.
The delivery system may further comprise sensors for monitoring the characteristics of the gaseous heat carrier. According to one embodiment, there is provided means to monitor the temperature and/or relative humidity of the gaseous heat carrier at various positions within the system.
In one embodiment, the means for monitoring the temperature is provided by thermocouples installed at locations in the system as required. In one embodiment, the system further comprises a temperature sensor array comprising one or more removable thermocouples. Appropriate thermocouples are known in the art and include, surface probes, thermocouple probes including grounded thermocouples, ungrounded thermocouples and exposed thermocouples or combinations thereof.
According to one embodiment, the system comprises devices for monitoring the exit of gaseous heat carrier. According to one embodiment, this can include, for example a composition monitor and flow meter.
In one embodiment, if the sensors detect excess air or water in the heated gaseous carrier, the incoming air, live steam and/or aqueous liquid being brought into the system is decreased.
In one embodiment of the invention, the sensing elements for monitoring contamination levels on a surface are dynamically controlled, optionally in conjunction with a Control System that is designed to maximize energy production/recovery, for enhanced efficiency.
13 frost tests were conducted with the moisture-laden air or plain air. Table 1 below summarizes the results of the 13 frost tests, and includes an assessment of the wing condition at the end of each test.
In all tests performed in frost conditions, the frost accumulation did not exceed 0.2 mm on the wing test bed; this is considered typical accumulation for a naturally occurring frost event. Outside ambient temperatures ranged from 3.9 to −23.5° C. in the 13 tests.
The de-icing procedures employed during frost testing consisted of one-step (hot air only) and two-step (moisture-laden air followed by hot air) operations. Due to the small amounts of contamination present on the surface of the wing in the frost tests performed, hot air alone was employed in all but four of the tests. Each of the tests will be further discussed below:
When Tests ID #1, ID #2 and ID #6 are removed from the analysis, due to deficiencies in the system outputs in all three tests, the average frost de-icing and drying time produced by the delivery system was 4.9 minutes.
In general, no residual water was created on the wing or in quiet areas due to the melting of frost contamination with the delivery system. Due to the thin layer of contamination present in natural frost tests, the frost was rapidly vaporized, resulting in dry wings at the end of testing.
The hot air application alone was capable of de-icing and drying the wing in most tests performed, especially those performed at warmer temperatures. Moisture-laden air applications did produce an increase in wing temperatures in the frost tests performed with moisture-laden air, however the moisture-laden air application also produced more water that needed to be dried. At colder temperatures, a benefit could be achieved by employing a short exposure to moisture-laden air before Hot air. More testing in natural frost conditions may pinpoint the threshold for use of moisture-laden air for frost applications.
An additional four frost tests (see Table 2) support the frost test results presented in Table 1.
The average de-icing and drying times of the frost tests presented in the Table 2 was 3.5 minutes. At the warmer temperatures experienced during these tests, no benefit was gained by employing moisture-laden air prior to Hot air.
11 tests were performed with the delivery system in ice conditions on the wing test bed. Table 3 summarizes the results of the ice tests, and includes an assessment of the wing condition at the end of each test.
Tests performed with lower levels of ice contamination (0.1 to 1.6 mm of ice) indicated that the delivery system was capable of de-icing and drying this level of ice, with little or no residual water created by the de-icing process. Tests ID #12 and ID #13 demonstrated that moisture-laden air, followed by a switch Hot air to dry, was a more effective procedure for quantities of ice in this range in comparison to Hot air alone. At 0° C. and with low levels of ice, the moisture-laden air and Hot air procedure de-iced and dried the wing in nearly two minutes fewer than the test that employed Hot air alone, even though the levels of contamination were slightly higher in the moisture-laden air test. For this reason, all subsequent tests in ice conditions employed moisture-laden air. During subsequent tests, a strong emphasis was placed on examining the de-icing and drying capabilities of moisture-laden air and Hot air in extreme cases of ice accumulation (as high as 3 cm of ice). Outside ambient temperatures ranged from −8.1° C. to −21.1° C. in the 8 tests performed.
The results of tests with the delivery system in ice conditions were extremely impressive, especially considering the high quantities of ice employed in testing and the extreme cold temperatures under which some of the tests were performed. Each of the tests shown in Table 3 will be further discussed below:
When the total de-icing times for Tests ID #23 and ID #31 were halved, as testing was performed over two wing sections, the average de-icing and drying time in the 11 tests performed in ice conditions with the delivery system was 8.2 minutes.
Residual water created by the melting of frozen contaminants was observed to drip in wing quiet areas and/or under the wing. The amount of residual water appeared to be directly related to the amount of frozen contaminant present on the wing at the start of the de-icing process. The presence of residual water would require that aircraft surfaces be treated with a light spray of de-icing fluid following a de-icing process with moisture-laden air and Hot air in these conditions.
In addition to the 11 ice tests presented in table, an additional two ice tests with the delivery system are described Table 4.
The average de-icing and drying times of these ice tests was 5 minutes. The average de-icing time presented in Table 4 is lower than that observed in the tests described in Table 3, but the ambient temperatures of the two tests were warm and the levels of ice contamination were low in comparison to the majority of the other ice tests.
10 snow tests were conducted using moisture-laden air and Hot air. Table 5 summarizes the results of the snow tests, and includes an assessment of the wing condition at the end of each test.
As was the case with the ice tests performed with moisture-laden air and Hot air, a strong emphasis was placed on examining the de-icing and drying capabilities of delivery system in extreme cases of snow accumulation (as high as 9 cm of snow). Outside ambient temperatures ranged from −1.5° C. to −23.5° C. in the 10 tests performed.
The results of tests with the delivery system in snow conditions were extremely impressive, especially considering the large quantities of snow employed in testing and some of the cold temperatures under which testing was performed. Each of the tests shown in Table 5 will be further discussed below:
When the total de-icing times for Tests ID #20 and ID #21 were halved, as the tests were performed over two wing locations, the average de-icing and drying time of the delivery system in snow conditions was 7.5 minutes.
Residual water created by the melting of snow contamination was observed to drip in wing quiet areas or under the wing. The amount of residual water appeared to be directly related to the amount of frozen contaminant present on the wing at the start of the de-icing process. The presence of residual water would require that aircraft surfaces be treated with a light spray of de-icing fluid following a de-icing process with moisture-laden air and Hot air in these conditions.
In addition to the 10 snow tests presented in Table 5, additional two snow tests are described in Table 6.
The average de-icing and drying times of the snow tests presented in Table 6 was 10.6 minutes. The average de-icing time presented in the Table 6 is higher than that observed in Table 5, but it is noteworthy that the density of the snow employed in the Table 6 tests was 579 g/L, which was nearly the double of any snow density measured in the Table 5 tests. In addition, the contamination range in the Table 6 tests was very high, and the snow was heavily compacted on the wing.
In addition to the tests performed in frost, ice and snow conditions, two tests were performed with the wing contaminated with various combinations of snow, ice and frost. Table 7 summarizes the two tests performed in conditions of mixed contamination.
The results of tests with the delivery system in mixed contamination conditions were as equally impressive as in the other conditions tested. The two tests shown in Table 7 will be further discussed below:
Residual water created by the melting of mixed contamination in these tests was observed to drip in wing quiet areas or under the wing. The amount of residual water appeared to be directly related to the amount of frozen contaminant present on the wing at the start of the de-icing process. If conditions are such that the deicing is to be followed by anti-icing, the presence of small amounts of residual water is of no consequence. If anti-icing is not required, the water can be eliminated by providing for a longer drying time or treating the aircraft surfaces with a light spray of de-icing fluid following a de-icing process with moisture-laden air and hot air in these conditions.
It is obvious that the foregoing embodiments of the invention are exemplary and can be varied in many ways. Such present or future variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
According to one embodiment of the invention, there is provided a Delivery Head System for removing contaminants from airplane engines. Contaminants such as snow and ice can clog engine fans, damaging the fan blades, hampering fan rotation and restricting the flow of air into the engine. The current methods of removing contaminants from airplane engines involve directing streams of hot dry air and/or glycol mixtures into the engine intake. The use of glycol, again as discussed above, is problematic due to environmental, as well as cost, factors. Furthermore, there is industry resistance to the use of glycol as a contaminant removal agent for engines.
For the purposes of engine de-icing, engine manufacturers need to limit the temperatures to which their products are exposed. These temperature limits can be in the range of 50° C.-60° C. These limits prevent the use of steam at normal pressures. By using a gaseous heat carrier additional heat energy can be transmitted through the phase change of the water vapour, or moisture content while respecting the temperature limitations required by individual manufacturers on specific engines.
The Delivery Head System for removing contaminants from an airplane engine, according to one embodiment of the invention, comprises a Delivery Head with a generally circular inflatable chamber. With reference to
The Delivery Head for delivering a gaseous heat carrier to an airplane engine according to one embodiment of the invention comprising a generally inflatable chamber having a diameter similar to that of the intake of an airplane engine. A worker skilled in the art will appreciate that the size of the Delivery Head is important to ensure that the entire surface of the engine is treated with the gaseous heat carrier while at the same time minimizing the wasted gaseous heat carrier, which would occur for example if the diameter of the Delivery Head is in excess of that of the engine intake. According to one embodiment of the invention, the diameter of the inflatable chamber will be between 3 and 13 feet. According to one embodiment, the diameter of the inflatable chamber will be between 3 and 8 feet. According to one embodiment, the diameter of the inflatable chamber will be between 6 and 12 feet.
According to one embodiment, a system of different sized and interchangeable delivery heads are be provided to enable the use of the Delivery Head System on a variety of different sizes of airplane engines. According to one embodiment, the inflatable chamber comprises two or more circular concentric sub-chambers. In this case different rings of sub-chambers could be inflated depending on the diameter of the engine intake to be treated.
With reference to
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/CA2008/000928 | 5/12/2008 | WO | 00 | 11/6/2009 |
| Number | Date | Country | |
|---|---|---|---|
| 60917636 | May 2007 | US | |
| 60917640 | May 2007 | US |
