Patent Publication Number: US-2020277074-A1

Title: Airborne aerodynamic arrangement

Description:
TECHNOLOGICAL FIELD 
     This invention relates to an airborne internal air cooling system, and in particular, to providing a required air pressure coefficient at an area of location of an air inlet port and/or an air outlet port of the internal airborne cooling system. 
     BACKGROUND 
     An airborne Heating Cooling Ventilation (HCV) system is commonly used to control environmental conditions for airborne avionics and electro-mechanical systems. A typical HCV system utilized in piloting or unmanned aerial vehicles, missiles and other subsonic flying platforms includes an internal air passage, wherein air flowing from the exterior of the flying vehicle is collected by an air inlet port and is then directed to airborne avionic components that can produce a large amount of heat when in operation. The air used for cooling is discharged through an air outlet port. 
     For effective operation of the airborne cooling system, a pressure gradient should be provided within the HCV system. This can, for example, be achieved by providing a positive pressure coefficient (Cp&gt;0) at the air inlet port of the cooling air duct. This condition enhances air pushing into the HCV system. In turn, an effective exhaust of the air from the HCV system requires a negative pressure coefficient (Cp&lt;0) at the air outlet port. The pressure gradient must have enough magnitude to provide required air mass flow through the internal air passage of the HCV system. 
     Various approaches and techniques are known in the art to provide a desired pressure gradient within the air passage. One of the approaches is to find, on the surface of the flying vehicle, locations where the desired characteristics of the pressure coefficient are produced at flight conditions, and to arrange the air inlet port and the air outlet port at these locations, correspondingly. Such locations on flying platforms are known for cooling systems of conventional aviation. However, to locate places with positive and negative pressure coefficients becomes more difficult in the case of autonomous cooling systems mounted within external payloads, such as pods, booms or detachable payloads, which are not integrated with the aircraft&#39;s general air cooling system. 
     Various arrangements are also known in the art for facilitating entrance of the air into the air duct of the cooling systems. For example, arrangements are known that utilize scoops, internal pumps and/or fans arranged at the air inlet and outlet ports. However, such arrangements suffer from complexity, extra energy consumption and weight penalty. 
     For example, U.S. Pat. No. 3,247,676 describes an arrangement for obtaining a stream of relatively cool air on board an aircraft in flight. The arrangement includes an air inlet on the exterior of the aircraft with an opening facing generally in the direction of relative air flow, and means for drawing air in through said inlet opening. 
     U.S. Pat. No. 4,674,704 describes a direct air cooling system for electronics carried by aircraft. The cooling system provides a submerged air scoop which directs outside air to several electronic modules. The air flows through passages in the modules which are adjacent to circuit boards bearing discrete electronic components. A foil layer and aluminum fin stock help transfer heat from the electronic components to the directed air. 
     U.S. Pat. No. 6,575,402 describes a cooling system for a hybrid aircraft. The cooling system includes an inlet which extends through the body to communicate airflow to a powerplant subsystem and out through an exhaust within a rotor duct. In a hover mode, there is a significant low-pressure area created inside the rotor duct by the rotor system. The low-pressure area within the rotor duct assists in drawing air through the inlet and over the engine via the exhaust. A cooling fan is located adjacent the inlet to augment cooling-air flow. 
     GENERAL DESCRIPTION 
     Despite prior art in the area of techniques for enhancing operation of cooling systems, there is still a need in the art to provide a novel arrangement that can provide a required air pressure coefficient at a desired area on the external surface of a flying platform. According to the invention, such desired area is in the vicinity of the air inlet port and/or air outlet port of an airborne internal cooling system mounted on a flying platform. 
     The present invention satisfies the aforementioned needs in the art by providing a novel airborne aerodynamic arrangement for providing a required air pressure coefficient at the areas of location of one or more air ports of an internal cooling system of a flying platform. The air ports are one or more air inlet ports and one or more outlet ports which are arranged at corresponding desired areas in an external surface of the flying platform. 
     According to an embodiment of the present invention, the aerodynamic arrangement includes one or more airfoil-shaped bodies arranged on the external surface of the platform at the areas of the air inlet port(s) and/or air outlet port(s). Each airfoil-shaped body is configured for providing a negative pressure coefficient at the corresponding desired area on one side of the airfoil-shaped body and a positive pressure coefficient at the corresponding desired area on the other side of the airfoil-shaped body, when the airfoil-shaped body is oriented at a suitable angle of attack to an oncoming air flow. 
     According to an embodiment of the present invention, the aerodynamic arrangement can provide a required air pressure gradient within the internal air passage between an air inlet port and an air outlet port of an airborne cooling system. 
     According to an embodiment of the present invention, the airfoil-shaped body is cambered. The side of the airfoil-shaped body, where the negative pressure coefficient is generated, is at least partially convex. According to this embodiment, the other side of the airfoil-shaped body, where the positive pressure coefficient is generated, is also at least partially convex, however it has a curvature less than a curvature of the side where the negative pressure coefficient is generated. 
     According to an embodiment of the present invention, the other side of the airfoil-shaped body, where the positive pressure coefficient is generated, is either at least partially concave or flat. 
     According to an embodiment of the present invention, the airfoil-shaped body is located near the air inlet port. The side of the airfoil-shaped body, where the negative pressure coefficient is generated, is directed outwardly from the inlet port. In this case, the inlet port is located in the vicinity of the side where the positive pressure coefficient is generated to provide a positive pressure coefficient in the corresponding desired area of location of the air inlet port when the oncoming air flow bypasses the airfoil-shaped body. 
     According to an embodiment of the present invention, the side of the airfoil-shaped body, where the negative pressure coefficient is generated, is located near the air outlet port. This size is directed inwardly to the air outlet port to provide a negative pressure coefficient in the corresponding desired area of location of the air outlet port when the oncoming air flow bypasses the airfoil-shaped body. 
     According to one embodiment of the present invention, the airfoil-shaped body is located above the air inlet port and/or the air outlet port. 
     According to another embodiment of the present invention, the airfoil-shaped body is located under the air inlet port and/or the air outlet port. 
     According to an embodiment of the present invention, the arrangement further includes airfoil-shaped body and an air scoop mounted over the air inlet port. The air scoop includes a scoop base attached to the external surface of the flying platform and surrounding the air inlet port. A scoop leading edge forms an inlet scoop opening front-oriented with respect to the direction of the oncoming air flow. 
     According to an embodiment of the present invention, the arrangement further includes airfoil-shaped body and an air scoop mounted over the air outlet port. In this case, the air scoop includes a scoop base attached to the external surface of the flying platform and a scoop leading edge forming an outlet scoop opening back-oriented with respect to the direction of the oncoming air flow. 
     According to an embodiment of the present invention, the arrangement further includes airfoil-shaped body and an air louver mounted over the air outlet port. In this case, the air louver forms an outlet opening back-oriented with respect to the direction of the oncoming air flow. 
     According to an embodiment of the present invention, the airfoil-shaped body is arranged over the air inlet port arranged in the external surface of the platform, and includes an air duct arranged within the airfoil-shaped body. The air duct is coupled to the air inlet port for providing an air passage from the air inlet port to an air duct opening arranged on the side of the airfoil-shaped body where the positive pressure coefficient is generated. 
     According to an embodiment of the present invention, the airfoil-shaped body is arranged over the air outlet port arranged in the external surface of the platform and includes an air duct arranged within the airfoil-shaped body. The air duct is coupled to the air outlet port for providing an air passage from the air outlet port arranged to an air duct opening arranged on the side of the airfoil-shaped body where the negative pressure coefficient is generated. 
     According to an embodiment of the present invention, the airfoil-shaped body includes an airfoil-shaped body portion and an aerodynamic deflectable flap portion. The airfoil-shaped body portion includes a rounded leading edge, a sharp trailing edge, an upper surface and a lower surface. According to an embodiment, the airfoil-shaped body portion has a symmetrical shape with a symmetric curvature of the upper surface and the lower surface, however other configurations are also contemplated. The aerodynamic flap portion is pivotally mounted on the trailing edge (i.e. at the rear end) of the airfoil-shaped body portion. 
     According to an embodiment of the present invention, the airfoil-shaped body has a shape with a rounded leading edge followed by a sharp trailing edge with a symmetric curvature of both sides of the airfoil-shaped body, however other configurations are also contemplated. According to this embodiment, the airfoil-shaped body is rotatably mounted on the surface of the flying platform, and is rotatable to alter the desired angle of attack of orientation of the airfoil-shaped body to the oncoming air flow. 
     The airborne aerodynamic arrangement of the present invention has many of the advantages of the prior art techniques, while simultaneously overcoming some of the disadvantages normally associated therewith. 
     The airborne aerodynamic arrangement of present invention allows arranging air inlet or air outlet ports of an internal cooling system at the locations which are most optimal for cooling effectiveness, structure strength and payload functionality. 
     The airborne aerodynamic arrangement of the present invention does not depend on the type of cooling system and can be used for a broad range of cooling purposes. 
     The airborne aerodynamic arrangement according to the present invention is mostly helpful when operation of the payload requires effective cooling with minimum energy consumption and within a strictly limited internal volume, and especially when utilization of pumps, air fans or other devices that can provide pressure distribution within a cooling air duct, are not desirable. 
     The airborne aerodynamic arrangement according to the present invention may be readily conformed to complexly shaped surfaces and contours of a flying platform. 
     The airborne aerodynamic arrangement according to the present invention may be efficiently manufactured. 
     The installation of the airborne aerodynamic arrangement to a flying platform is relatively quick and easy and can be accomplished without substantially altering the platform, with which it is to be associated. 
     The airborne aerodynamic arrangement according to the present invention is of durable and reliable construction. 
     The present invention also satisfies the aforementioned needs in the art by providing a novel method for providing a required air pressure coefficient at an area of location of at least one air port of an internal cooling system of a flying platform. The air port is selected from an air inlet port and an air outlet port, and arranged at a desired area in an external surface of the flying platform. The method includes providing an airfoil-shaped body on the external surface at the corresponding area of the air port for generating a negative pressure coefficient at the corresponding desired area on one side of the airfoil-shaped body and a positive pressure coefficient at the corresponding desired area on the other side of the airfoil-shaped body, when the airfoil-shaped body is oriented at a suitable angle of attack to an oncoming air flow. 
     There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows hereinafter may be better understood. Additional details and advantages of the invention will be set forth in the detailed description, and in part will be appreciated from the description, or may be learned by practice of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: 
         FIG. 1  illustrates a general concept for providing a desired pressure coefficient at an area of location of an inlet and outlet air ports of an internal cooling system of a flying platform; and 
         FIGS. 2 through 10  illustrate examples of configurations of an aerodynamic arrangement for providing a desired pressure coefficient at an area of location of an inlet and outlet air ports on an external surface of the flying platform, according to various embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The principles and operation of the aerodynamic arrangement for providing a required air pressure coefficient at an area of location of at least one air port of an internal cooling system of a flying platform according to the present invention may be better understood with reference to the drawings and the accompanying description, it being understood that these drawings and examples in the description are given for illustrative purposes only and are not meant to be limiting. It is to be understood that these drawings, which are not necessarily to scale, are given for illustrative purposes only and are not intended to limit the scope of the invention. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments. The same reference numerals and alphabetic characters will be utilized for identifying those components which are common in the aerodynamic arrangement and its components shown in the drawings throughout the present description of the invention. 
     Referring to  FIG. 1 , a general concept for providing a desired pressure coefficient at a required location on an external surface  16  of a flying platform  11  is illustrated, according to an embodiment of the present invention. The flying platform  11  has a pod  111  including a payload (not shown). The pod  111  is equipped with an autonomous internal air cooling system  12  arranged within the pod  111 . The internal cooling system  12  includes an air inlet port  14  and an air outlet port  15 . In operation, air enters at the air inlet port  14  and passes through an internal cooling volume (not shown) of the cooling system  12  to the air outlet port  15  from which the air exits. 
     The present invention is not bound to any specific implementation of the internal cooling system  12  and can, for example, be used with any known type of a direct air cooling system. The air inlet port  14  and the air outlet port  15  are arranged at corresponding desired areas in an external surface  16  of the pod  111 . 
     The air inlet port  14  and the air outlet port  15  can, for example, be implemented as a single circular orifice or as a plurality of circular orifices located at the corresponding desired areas in the external surface  16  of the pod  111 . Likewise, the air inlet and outlet ports  14  and  15  can be implemented as one or more slots. When desired, the air inlet port  14  and the outlet port  15  can be equipped with a corresponding scoop (not shown) or with a louver device (not shown) mounted over the inlet port  14  and the outlet port  15 . 
     It should be noted that the inventive concept of the present invention is not limited to pods or to any other specific components of the flying platform  11 . Likewise, the inventive concept of the present invention is not limited to any specific type of the flying platform. It can, for example, be utilized in aircrafts, unmanned aerial vehicles, missiles and other subsonic flying vehicles, which include internal cooling systems with air flowing through an internal volume of the cooling system in order to cool avionics and electro mechanical systems (not shown) of the payload as well as other components that can produce a large amount of heat when in operation. 
     As described above, for effective operation of the internal cooling system  12 , a positive pressure coefficient (Cp&gt;0) should be provided at an area  140  where an air inlet port  14  of the cooling system  12  is located. This condition enhances air suction into the air inlet port  14 . In turn, an effective exhaust of the air from the internal cooling system  12  requires a negative pressure coefficient (Cp&lt;0) at an area  150  of the air outlet port  15 . 
     Thus, according to the present invention, an aerodynamic arrangement  10  is used to provide a required positive pressure coefficient at an area  140  of the air inlet port  14  of the internal cooling system  12  employed in the flying platform  11 . Likewise, an aerodynamic arrangement  10  is used to provide a required negative pressure coefficient at the area  150  of the air outlet port  15 . It should be understood that the internal cooling system  12  may include any desired number of air inlet ports and air outlet ports, and each air port can be equipped with the corresponding aerodynamic arrangement  10 . 
     The aerodynamic arrangement of the present invention can, for example, be used in a subsonic aircraft to cool electronic modules arranged in an airborne pod equipped with an autonomous air cooling system that is not integrated with a main cooling system of the aircraft carrying this airborne pod. A pod equipped with an autonomous internal air cooling system can, for example, be mounted under the fuselage or under the main wings or at any other desired location of an aircraft or any other flying platform. It should be noted that the aerodynamic arrangement  10  of the present invention can also be used in any detachable airborne blocks. 
     Referring to  FIG. 2 , an aerodynamic arrangement  20  for providing a desired pressure distribution on an external surface of the flying platform  11  is illustrated, according to an embodiment of the present invention. According to this embodiment of the present invention, the aerodynamic arrangement  20  includes an airfoil-shaped body  17  arranged on the external surface  16  of the flying platform  11  at the area  140  of location of the air inlet port  14 . 
     The airfoil-shaped body  17  may have a substantially rectangular plan profile along an axis (not shown) perpendicular to the external surface  16 , however other configurations of the profile along the axis (not shown) perpendicular to the external surface  16  are also contemplated, for example: swept-back or swept forward, with dihedral or anhedral and/or with a variable taper ratio. 
     The airfoil-shaped body  17  includes a leading edge  171  followed by a trailing edge  172 . The airfoil-shaped body  17  also includes a suction surface  173  and a pressure surface  174  extending between the leading edge  171  and the trailing edge  172 . The leading edge  171  is the foremost edge of airfoil-shaped body  17  that first contacts an oncoming air flow  18  and splits the air flow  18  into two curved air streamlines. The trailing edge  172  of the airfoil-shaped body  17  is its rear edge, where the airflow split by the leading edge  171  rejoins. 
     The suction surface  173  and the pressure surface  174  are two opposite surfaces of the airfoil-shaped body  17  between the leading edge  171  and the trailing edge  172 . The suction surface  173  is defined as the surface that provides a higher velocity of the bypassing air flow, and a negative pressure coefficient (C p &lt;0) in the vicinity of the suction surface  173  when the airfoil-shaped body  17  is oriented at a suitable angle of attack to the oncoming air flow  18 . In turn, the pressure surface  174  is defined as the surface that provides a comparatively lower velocity of the bypassing air flow than the suction surface  173 , and a positive pressure coefficient (C p &gt;0) in the vicinity of the pressure surface  174  at a corresponding angle of attack. 
     The lower pressure properties of the suction surface  173  and the higher pressure properties of the pressure surface  174  are determined by the shape of the airfoil-shaped body  17  and by the orientation of the airfoil-shaped body  17  to the oncoming air flow  18 . The desired magnitudes of the pressure coefficient can be achieved in a broad range of the angle of attack (flight envelope). 
     It should be noted that dimensions of the airfoil-shaped body  17  of the present invention are such that an aerodynamic forces and moments generated by the airfoil-shaped body  17  are negligible when compared with the aerodynamic forces and the moments providing motion of the flying platform  11 . In this case, the aerodynamic effect of the airfoil-shaped body  17  does not cause a significant effect on the flying performance of the flying platform  11 . 
     According to an embodiment of the present invention, an area of aerodynamic surface of the airfoil-shaped body  17  does not exceed 2% of the area of a main aerodynamic surface (i.e., a main wing of the flying platform). 
     According to the embodiment shown in  FIG. 2 , the airfoil-shaped body  17  has a cambered shape, and is mounted above the air inlet port  14 . As shown in  FIG. 2 , the suction surface  173  is an upper side of the airfoil-shaped body  17 , while the pressure surface  174  is a lower side of the airfoil-shaped body  17 . 
     As shown in  FIG. 2 , the suction surface  173  is convex, while the pressure surface  174  is concave, however, other shape configurations are contemplated, provided that a negative pressure coefficient (C p &lt;0) is generated on the upper side (i.e. on the suction surface  173 ), while a positive pressure coefficient (C p &gt;0) is generated on the lower side (i.e. on the pressure surface  174 ) of the airfoil-shaped body when the oncoming air flow bypasses the airfoil-shaped body. It should be noted that in this configuration, the airfoil-shaped body can be oriented even at zero angle of attack to an oncoming air flow  18 . 
     When desired, the pressure surface  174  of the airfoil-shaped body  17  may be flat or even convex, provided that the upper side has a curvature greater than the curvature of the lower side. 
     The suction surface  173  of the airfoil-shaped body  17  should be directed outwardly from the air inlet port  14  to provide a negative pressure coefficient above the airfoil-shaped body  17  when the oncoming air flow bypasses the airfoil-shaped body  17 , and to provide a positive pressure coefficient in the corresponding desired area of location of the air inlet port  14 , which is below the airfoil-shaped body  17 . 
     According to the embodiment shown in  FIG. 2 , the airfoil-shaped body  17  is arranged above the air inlet port  14 . Such configuration can protect the internal cooling system from penetration of conduced water droplets presented in the atmospheric air into the air inlet port  14 . However, when desired, the airfoil-shaped body  17  can be mounted upside-down, and arranged under the air inlet port  14 , mutatis mutandis. 
     Referring to  FIG. 3 , an aerodynamic arrangement  30  for providing a required air pressure coefficient at an area of location of an air port of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to another embodiment of the present invention. The aerodynamic arrangement  30  differs from the aerodynamic arrangement  20  shown in  FIG. 2  by the fact that the airfoil-shaped body  17  is turned upside-down and arranged on the external surface  16  of the flying platform  11  at the desired area  150  of location of the air outlet port  15 . 
     According to the embodiment shown in  FIG. 3 , the airfoil-shaped body  17  has a cambered shape, and is mounted above the air outlet port  14 . The suction surface  173  of the airfoil-shaped body  17  is located near the air outlet port  15  and is directed inwardly to the air outlet port  15 . This provision provides a negative pressure coefficient in the corresponding area  150  of location of the outlet port  15  when the oncoming air flow  18  bypasses the airfoil-shaped body  17 . 
     As shown in  FIG. 3 , the airfoil-shaped body  17  is arranged above the air outlet port  15  to protect the internal cooling system from penetration of conduced water droplets presented in the atmospheric air into the air outlet port  15 . However, when desired, the airfoil-shaped body  17  can be arranged under the air outlet port  15 , mutatis mutandis. 
     Referring to  FIG. 4 , an aerodynamic arrangement  40  for providing a required air pressure coefficient at an area of location of air ports of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to a further embodiment of the present invention. According to this embodiment, the aerodynamic arrangement  10  includes two airfoil-shaped bodies  17  arranged on the external surface  16  at both areas  140  and  150  of location of the inlet port  14  (similar to the embodiment shown in  FIG. 2 ) and location of the air outlet port  15  (similar to the embodiment shown in  FIG. 3 ). 
     Referring to  FIG. 5 , an aerodynamic arrangement  50  for providing a required air pressure coefficient at an area of location of an air port of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to yet another embodiment of the present invention. The aerodynamic arrangement  50  differs from the aerodynamic arrangement  20  shown in  FIG. 2  by the fact that it further includes an inlet air scoop  51  mounted on the area  140  over the air inlet port  14  and is attached to the external surface  16  of the flying platform  11 . 
     The inlet air scoop  51  is a forward facing air scoop that includes a scoop base  52  attached to the external surface  16  of the flying platform and surrounding the air inlet port  14 , and a scoop leading edge  53 . The scoop leading edge  53  forms an inlet scoop opening  54 . As shown in  FIG. 5 , the inlet scoop opening  54  is a forward facing inlet that is front-oriented with respect to the direction of the oncoming air flow  18 . In operation, the inlet air scoop  51  brings the oncoming air flow  18  from exterior of the flying platform  11  to the air inlet port  14 . 
     The suction surface  171  of the airfoil-shaped body should be directed outwardly from the air inlet scoop  51  to provide a negative pressure coefficient above the airfoil-shaped body  17  and a positive pressure coefficient in the corresponding desired area  140  of location of the air inlet scoop  51  when the oncoming air flow bypasses the airfoil-shaped body  17 . 
     According to this embodiment, the airfoil-shaped body  17  is arranged above the air scoop  51 , however, when desired, the airfoil-shaped body  17  can be arranged under the air inlet scoop  51 , mutatis mutandis. 
     Referring to  FIG. 6 , an aerodynamic arrangement  60  for providing a required air pressure coefficient at an area of location of an air port of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to still a further embodiment of the present invention. The aerodynamic arrangement  60  differs from the aerodynamic arrangement  50  shown in  FIG. 5  by the fact that it includes an outlet air scoop  61  mounted on the area  150  over the air outlet port  15  and is attached to the external surface  16  of the flying platform  11 . 
     The outlet air scoop  61  includes a scoop base  62  attached to the external surface  16  of the flying platform  11  and surrounding the air outlet port  15 , and a scoop leading edge  63 . The scoop leading edge  63  forms an outlet scoop opening  64 . As shown in  FIG. 6 , the outlet scoop opening  64  is back-oriented with respect to the direction of the oncoming air flow  18 . In operation, the outlet air scoop  61  enhances exit of the air flow passing through the cooling air duct (not shown) from the air outlet port  15 . 
     According to the embodiment shown in  FIG. 6 , the suction surface  171  of the airfoil-shaped body  17  is located above the outlet air scoop  61  and is directed inwardly to the outlet scoop opening  64  of the outlet air scoop  61 . This provision provides a negative pressure coefficient in the corresponding area  150  of location of the outlet air scoop  61  when the oncoming air flow  18  bypasses the airfoil-shaped body  17 . 
     As shown in  FIG. 6 , the airfoil-shaped body  17  is arranged above the outlet air scoop  61 , however, when desired, the airfoil-shaped body  17  can be arranged under the outlet air scoop  61 , mutatis mutandis. 
     It should be noted that the aerodynamic arrangement of the present invention may be equipped with an air louver (not shown) instead of the scoop shown in  FIG. 6 , mutatis mutandis. Thus, according to an embodiment of the present invention, the arrangement includes airfoil-shaped body and an air louver mounted over the air outlet port. In this case, the air louver provides an outlet opening back-oriented with respect to the direction of the oncoming air flow. 
     Referring to  FIG. 7 , an aerodynamic arrangement  70  for providing a required air pressure coefficient at an area of location of an air port of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to still a further embodiment of the present invention. The aerodynamic arrangement  70  includes an airfoil-shaped body  71  arranged on the external surface  16  of the flying platform  11  at the area  140  over the air inlet port  14  arranged in the external surface  16 . The airfoil-shaped body  71  differs from the airfoil-shaped body ( 17  in  FIG. 2 ) by the fact that it includes an air duct  72  (shown by dashed lines) arranged within the airfoil-shaped body  71 . The air duct  72  is coupled to the air inlet port  14  and provides an air passage from the air inlet port  14  to an opening  73  arranged on a pressure surface  74  of the airfoil-shaped body  71 . Since the opening  73  is located in the area of a positive pressure coefficient, it facilitates ingression of the air into the air duct  72 , and then into the cooling system ( 12  in  FIG. 1 ) through the air inlet port  14 . 
     Referring to  FIG. 8 , an aerodynamic arrangement  80  for providing a required air pressure coefficient at an area of location of an air port of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to still a further embodiment of the present invention. The aerodynamic arrangement  80  includes an airfoil-shaped body  81  arranged on the external surface  16  of the flying platform  11  at the area  150  over the air outlet port  15  arranged in the external surface  16 . The airfoil-shaped body  81  differs from the airfoil-shaped body ( 17  in  FIG. 2 ) by the fact that it includes an air duct  82  arranged within the airfoil-shaped body  81 . The air duct  81  is coupled to the air outlet port  15  and provides an air passage from the air outlet port  15  to an opening  83  arranged on a suction surface  84  of the airfoil-shaped body  81 . Since the opening  83  is located in the area of a negative pressure coefficient, it facilitates exhaust of the air from the air outlet port  15  through the air duct  82  into the atmosphere. 
     It should be understood that invention is not bound to a specific shape of the opening  73  in  FIG. 7  and the opening  83  in  FIG. 8 . When desired, the openings  73  and  83  can be configured as a plurality of the perforation orifices. Likewise, the openings  73  and  83  can be configured as chord directional slots oriented in the direction of the main air flow stream or as lateral slots oriented in the direction of a spanwise flow stream. 
     Referring to  FIG. 9 , an aerodynamic arrangement  90  for providing a required air pressure coefficient at an area of location of an air port of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to still a further embodiment of the present invention. According to this embodiment of the present invention, the aerodynamic arrangement  90  includes an airfoil-shaped body  91  having two portions, such as an airfoil-shaped body portion  911  and an aerodynamic flap portion  912 . The airfoil-shaped body portion  911  includes a rounded leading edge  93 , a sharp trailing edge  94 , an upper surface  95  and a lower surface  96 . As shown in  FIG. 9 , the airfoil-shaped body portion  911  has a symmetrical shape with a symmetric curvature of the upper surface  95  and the lower surface  96 . It should be noted that when desired, the airfoil-shaped body portion  911  can, for example, have a cambered shape or any other desired asymmetrical shape. 
     The aerodynamic flap portion  912  is pivotally mounted on the trailing edge  94  of the airfoil-shaped body portion  91 . Shape of the airfoil-shaped body  91  alters when the aerodynamic flap portion  912  deflects up or down. In order to obtain a positive pressure coefficient on and above the upper surface  95  and a negative pressure coefficient on and under the lower surface  96 , cambering of the symmetrical airfoil-shaped body  91  can be achieved by deflecting the aerodynamic flap portion  912  up. This configuration of the airfoil-shaped body  91  is suitable for the air inlet port  14  located above the airfoil-shaped body portion  91  and for the air outlet port  15  located under the airfoil-shaped body portion  91 . 
     In turn, in order to obtain a negative pressure coefficient on the upper surface  95  and a positive pressure coefficient on the lower surface  96 , the aerodynamic flap portion  92  should be deflected down. This configuration of the airfoil-shaped body  91  is suitable for another case (not shown), when the air inlet port is located under the airfoil-shaped body portion  91  while the air outlet port is located above the airfoil-shaped body portion  91 . 
     Referring to  FIG. 10 , an aerodynamic arrangement  100  for providing a required air pressure coefficient at an area of location of an air port of an internal cooling system (not shown) of the flying platform  11  is illustrated, according to still a further embodiment of the present invention. According to this embodiment, the aerodynamic arrangement  110  includes an airfoil-shaped body  115  that is rotatably mounted on a surface of the flying platform  11 . The airfoil-shaped body  115  can, for example, be mounted on a shaft (not shown), and is rotatable around the shaft to alter the desired angle of attack of orientation of the airfoil-shaped body to the oncoming air flow. 
     According to the embodiment shown in  FIG. 10 , the airfoil-shaped body  115  includes a rounded leading edge  116  followed by a sharp trailing edge  117 , an upper surface  118  and a lower surface  119 . The airfoil-shaped body  115  has symmetrical shape with a symmetric curvature of the upper surface  118  and the lower surface  119 . Therefore, a negative pressure coefficient above the upper surface  118  and a negative pressure coefficient under the lower surface  119  can be achieved by providing a suitable orientation of the airfoil-shaped body  115  to the oncoming air flow  18 . 
     This configuration of the airfoil-shaped body  115  is suitable for the air inlet port  14  located under the airfoil-shaped body portion  115  and for the air outlet port  15  located above the airfoil-shaped body portion  115 . 
     As such, those skilled in the art to which the present invention pertains, can appreciate that while the present invention has been described in terms of preferred embodiments, the concept upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, systems and processes for carrying out the several purposes of the present invention. 
     The present invention is not limited to cooling systems, and the described arrangement can be used for providing a required air pressure at any desired areas on an external surface of a flying platform for any other purposes. 
     Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. 
     Finally, it should be noted that the word “comprising” as used throughout the appended claims is to be interpreted to mean “including but not limited to”. 
     It is important, therefore, that the scope of the invention is not construed as being limited by the illustrative embodiments set forth herein. Other variations are possible within the scope of the present invention as defined in the appended claims. Other combinations and sub-combinations of features, functions, elements and/or properties may be claimed through amendment of the present claims or presentation of new claims in this or a related application. Such amended or new claims, whether they are directed to different combinations or directed to the same combinations, whether different, broader, narrower or equal in scope to the original claims, are also regarded as included within the subject matter of the present description.