IR source, method and apparatus

Information

  • Patent Grant
  • 6521904
  • Patent Number
    6,521,904
  • Date Filed
    Friday, December 15, 2000
    24 years ago
  • Date Issued
    Tuesday, February 18, 2003
    22 years ago
Abstract
The invention is an apparatus for producing an IR (infra-red) signature. In the method, the apparatus is mounted on a target to give the target an infra-red signature whereby the target can be acquired by an appropriate weapon sensor.
Description




This invention relates to an IR (infra-red) source, and more particularly to a structure of an IR source to be used on targets to allow the siting of weapons having appropriate sensors on the target.











In the accompanying drawings:





FIG. 1

shows an exploded view of the apparatus.





FIG. 2

shows a side view of a target, in this case a drone aircraft, with the apparatus mounted thereon.





FIG. 3

shows a top view of the target depicted in FIG.


2


.





FIG. 4

shows a view of what an observer perceives from the IR source.











OVERVIEW




An overview of the apparatus of the present invention is depicted in FIG.


1


. The IR source


1


is comprised of a catalytic assembly


10


, which radiates when contacted by a first fluid


15


, positioned within an exit


17


of a housing


5


. Housing


5


is depicted in two parts to more clearly show that catalytic assembly


10


is positioned within exit


17


of housing


5


. It should further be understood that there can be multiple exits


17


each with a catalytic assembly


10


positioned therein.




The catalytic assembly


10


is comprised an element


50


with a catalyst


51


positioned thereon. The catalytic assembly


10


can be made from a single element or a plurality of elements.




The entrance


16


of housing


5


is adapted to be connected to the source of first fluid


15


, in this case the exhaust port of an internal combustion engine. The first fluid


15


enters the housing through entrance


16


and is directed through catalyst assembly


10


then out exit


17


.




The housing


5


comprises an exterior surface


19


with a partition


35


extending outwardly therefrom. The partition


35


is positioned such that a second fluid


8


flowing toward the downstream face


11


of catalytic assembly


10


will be deflected away from the downstream face


11


.




Within housing


5


, baffle


30


is positioned outwardly from the interior surface


18


to direct the first fluid


15


flow toward catalytic assembly


10


.





FIG. 2

shows the apparatus of

FIG. 1

mounted on a target


60


, in this case an aerial drone. The apparatus is connected to an engine


61


.such that the first fluid


15


, in this case the exhaust from the engine, causes the catalytic assembly to radiate. Catalytic assembly


10


is positioned in the exit


17


such that the generated radiation


75


is visible to a distant observer


70


.

FIG. 2

also shows that the engine


61


is integrated into the propulsion system, attached to a propeller


62


, of the target


60


.





FIG. 3

shows another view of target


60


to illustrate that multiple catalytic assemblies


10


can be employed.





FIG. 4

shows a schematic representation from the distant observer's perspective. The device is intended as an IR source that can be acquired by a sensor that is part of a weapon (not shown). The sensor is manipulated by the distant observer


70


. Thus an irradiance


71


at the location of the sensor, assumed to the distant observer


70


, must be sufficient for the sensor to detect.




DETAILED DESCRIPTION




Thus an irradiance


71


at the location of the sensor, assumed to the distant observer


70


, must be sufficient for the sensor to detect.




DETAILED DESCRIPTION




The catalytic assembly


10


is comprised of at least one element


50


with a catalyst


51


positioned thereon. As those skilled in the art will recognize, there are numerous structures for element


50


as well as numerous catalyst for catalyst


51


and still further numerous ways of positioning the catalyst on the element. Element


50


must be capable of radiating, elements providing greater emissivty are preferred. In the case of the present invention, a metallic, short channel element, woven metal 10×10 mesh constructed of Haynes


230


, was used. Other element structures such as expanded metal, gauze, foam, or monolith constructed of almost any material including metals or ceramics could be used.




It is preferred that the shape of the material chosen for element


50


, or most downstream element


50


in the case where multiple elements


50


are employed, provide a radiation pattern off the downstream face


11


in more than a single direction. An element


50


is comprised of members


52


, in this case wire woven into a mesh. Wire has a round cross-section that generates a hemispherical radiating pattern off the downstream face


11


. If the shape of the members at the downstream face were planar, a typical monolith, the members


52


would generate a radiation pattern in a single direction. It would be possible, however, to use members


52


with cooperating planer surfaces to generate a multidirectional radiation pattern. For example, two planar surfaces oriented at an acute angle to one another.




Depending upon the element chosen and the application, a single or multiple element catalytic assembly might be devised. The most downstream surface of the most downstream element


50


, based on the flow of the first fluid through the catalyst assembly, is defined as the downstream face


11


. In the case of a multiple element


50


catalytic assembly, it is preferred that the members


52


of respective elements


50


be offset to one another relative to the flow of the first fluid


15


through the catalytic assembly.




The catalyst


51


is application dependent, depending upon the composition and operating conditions of the first fluid


15


in combination with the weapon sensor and the range on which the target will be used. The catalyst must be positioned on the element, or elements, such that the catalytic assembly


10


when contacted with the first fluid


15


radiates. Positioning could be accomplished through any number of commonly used deposition techniques or integrated into the composition of the element. In the case of the present embodiment wherein the first fluid


15


is the exhaust gas of an internal combustion engine, any precious metal catalyst, such as platinum or palladium, could be used.




While this embodiment depicts the first fluid


15


as an exhaust gas of an internal combustion engine, this should not be considered a limitation of the invention. It is preferred that the invention utilize a first fluid


15


that is presently available onboard the target, the exhaust gas or a fuel. The present invention, however, will function as intended if the first fluid is ancillary to the target, for example a bottled fuel. In addition, it is anticipated that other engines, other than internal combustion, may be used to generate the second fuel


15


.




The housing


5


is the structure that holds the catalytic assembly


10


in the housing's exit


17


. The design of exit


17


is application dependent, but it is preferred that the opening be sized to permit the maximum exposure of the catalytic assembly


10


downstream face


11


to a distant observer. It should be realized, that the housing can be adapted to the first fluid source with multiple entrances


16


. The material selected for the housing is application dependent.




A partition


35


extends outwardly from the housing


5


exterior surface


19


. Where the target is moving, such as in the depicted aerial drone, the catalyst assembly


10


could be cooled by a second fluid


8


passing over the surface. It is preferred that the partition


35


be located upstream of the downstream face


11


, relevant to the flow of fluid


8


, to prevent as much as possible this cooling effect, in the presented embodiment thereby defining a partition angle


36


that is acute. The partition


35


also has an overhang


9


that extends beyond the width of the downstream face


11


to account for non-parallel second fluid


8


flow patterns.




When the housing


5


is adapted to be in fluid communication with the source of the first fluid, the passage created by the housing may have turns. In order to assure maximum utilization of the catalyst


51


, it is preferred that the first fluid be distributed equally throughout the catalyst assembly


10


. In the present embodiment, baffle


21


extends outwardly from the interior surface


18


of housing


5


to accomplish this objective. When baffle


21


is performing this function, as depicted in this embodiment, it is preferred that the baffle in cooperation with the downstream face define a baffle angle


22


that is acute. Baffle


21


, however, might be employed to simply reduce the pressure drop between entrance


16


and exit


17


. The shape and positioning of the baffle is based on the application, but in the preferred embodiment that baffle was given a fair surface and the surface was given a parabolic shape.




In the method of the present invention, the catalytic assembly


10


is engineered such that the catalyst


51


cooperates with the first fluid


15


to create a radiation


75


. The amount of radiation


75


required is dependent upon the sensor being used and the parameters of the range such as distance from sensor, which is illustrated herein as the distance from observer


70


to the target. The first fluid can either by a fluid onboard the target, exhaust gas or fuel, or from an ancillary source added to the target. To provide additional benefit to the observer by illuminating the target from multiple perspectives, multiple exits


17


each with a catalyst assembly


10


can be positioned at different locations on the target.



Claims
  • 1. An IR source comprisinga housing having an exterior surface, an entrance and an exit, a catalyst assembly positioned within the exit to allow a first fluid to pass there through, the catalyst assembly comprising at least two elements, the catalyst assembly having a downstream face, a majority of the downstream face visible through the exit, and a partition extending outwardly from the exterior surface adjacent to the exit for diverting a second fluid passing over the housing away from the downstream face.
  • 2. The IR source of claim 1 wherein the partition in cooperation with the downstream face defines a partition angle that is acute.
  • 3. The IR source of claim 2 wherein the partition has an overhang.
  • 4. The IR source of claim 2 wherein the housing has an interior surface and a baffle extending outwardly from the interior surface adjacent to the exit.
  • 5. The IR source of claim 4 wherein the baffle in cooperation with the downstream face defines a baffle angle that is acute, and the baffle and the partition are opposed.
  • 6. The IR source of claim 5 further comprising an engine having the exhaust port and the housing in fluid communication therewith.
  • 7. The IR source of claim 6 further comprising a target with the engine mounted therein.
  • 8. The IR source of claim 7 wherein the target has a propulsion system and the engine is integrated therein.
  • 9. The IR source of claim 5 wherein the baffle is contoured.
  • 10. The IR source of claim 1 wherein the housing has an interior surface and a baffle extending outwardly from the interior surface.
  • 11. The IR source of claim 10 further comprising an engine having the exhaust port and the housing in fluid communication therewith.
  • 12. The IR source of claim 10 wherein the baffle in cooperation with the downstream face defines a baffle angle that is acute.
  • 13. The IR source of claim 1 further comprising an engine having the exhaust port and the housing in fluid communication therewith.
  • 14. The IR source of claim 13 further comprising a target, the engine being mounted therein.
  • 15. The IR source of claim 13 wherein the target has a propulsion system and the engine is part thereof.
  • 16. The IR source of claim 1 wherein the housing defines a plurality of exits, each exit having a catalyst assembly mounted therein.
  • 17. The IR source of claim 16 wherein there are at least two exits opposed.
  • 18. The IR source of claim 1 wherein the catalyst assembly is comprised of a plurality of metallic, short-channel elements with a catalyst positioned thereon.
  • 19. An IR source comprisinga housing with an entrance and an exit, a catalyst assembly positioned within the exit to allow a first fluid to pass there through, the catalyst assembly comprised of at least one element having members, the members having an exterior surface, at least a portion of at least one exterior surface contoured to permit radiation in more than one direction, and the catalyst assembly having a downstream face, a majority of the downstream face visible through the exit.
  • 20. An IR source comprisinga housing with an entrance and an exit, a catalyst assembly positioned within the exit to allow a first fluid to pass there through, the catalyst assembly comprised of at least one element having members, the members having an exterior surface, at least a portion of at least two exterior surfaces cooperating to permit radiation in more than one direction, and the catalyst assembly having a downstream face, a majority of the downstream face visible through the exit.
  • 21. An IR source comprisinga housing having an exit, a catalyst assembly having a downstream face, the catalyst assembly positioned within the exit to allow a first fluid within the housing to exit and to permit the downstream face to be visible, and an engine having an exhaust port, the housing in fluid communication with the exhaust port.
  • 22. The IR source of claim 21 wherein the catalyst is comprised of at least two elements, the elements positioned in an offset pattern.
  • 23. The IR source of claim 22 wherein the housing has an exterior surface and further comprises a partition extending outwardly from the exterior surface adjacent to the exit.
  • 24. The IR source of claim 21 wherein the catalyst assembly is comprised of at least one element having members, the members having an exterior surface, at least two exterior surfaces cooperating to permit radiation in more than one direction.
US Referenced Citations (1)
Number Name Date Kind
6253540 Chew et al. Jul 2001 B1
Foreign Referenced Citations (1)
Number Date Country
405171917 Jul 1993 JP