Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C23/00—Influencing air flow over aircraft surfaces, not otherwise provided for
  • B64C23/005—Influencing air flow over aircraft surfaces, not otherwise provided for by other means not covered by groups B64C23/02 - B64C23/08, e.g. by electric charges, magnetic panels, piezoelectric elements, static charges or ultrasounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C2230/00—Boundary layer controls
  • B64C2230/06—Boundary layer controls by explicitly adjusting fluid flow, e.g. by using valves, variable aperture or slot areas, variable pump action or variable fluid pressure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C2230/00—Boundary layer controls
  • B64C2230/16—Boundary layer controls by blowing other fluids over the surface than air, e.g. He, H, O2 or exhaust gases
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C2230/00—Boundary layer controls
  • B64C2230/22—Boundary layer controls by using a surface having multiple apertures of relatively small openings other than slots
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T50/00—Aeronautics or air transport
  • Y02T50/10—Drag reduction

Definitions

• the present patent application relates to a mobile platform and method for applying a composition to a skin of a mobile platform.
• the present patent application provides a mobile platform, wherein the mobile platform comprises a skin, wherein the skin is provided with a plurality of openings, wherein the mobile platform comprises a separation device configured to separate one or more components from a fluid surrounding the mobile platform, and wherein the mobile platform is configured to form a composition of the separated components and to apply the composition via the openings to an outer side of the skin, wherein the composition to be applied differs from a composition of the fluid surrounding the mobile platform.
• the mobile platform applies a layer all around the skin via the plurality of openings in the skin, wherein the layer has a composition which differs from the fluid surrounding the mobile platform.
• the properties, such as the pressure, temperature, density, relative velocity and/or composition, of a layer of fluid situated close to the skin of the mobile platform hereby differ from the properties of the fluid.
• the relative velocity is the velocity at which the fluid comes into contact with the skin of the mobile platform.
• the friction forces are influenced by, among other things, the properties of the fluid, for instance a pressure, temperature, density, relative velocity and/or composition of the fluid.
• the mobile platform according to the first aspect further has the advantage that use of the separation device allows the properties of the layer surrounding the mobile platform to be modified with a composition which differs from the fluid, without gas bottles or other containers of components being required for this purpose in the mobile platform.
• the mobile platform can be an aeroplane, helicopter or other aircraft, but also a vessel or submersible craft.
• the mobile platform is preferably an aircraft or a submersible craft, most preferably an aircraft.
• “lift” or buoyancy is necessary to allow the mobile platform to maintain a stable position relative to a reference plane.
• the reference plane can for instance be the ground level or the sea level.
• This buoyancy can also be influenced by properties of the surrounding fluid, for instance a pressure, temperature, density, relative velocity and/or composition of the fluid.
• Application of a layer all around the mobile platform with properties differing from those of the fluid will therefore also change the lift or the buoyancy, which can result in ascent or descent of the mobile platform.
• Particularly in the case of aircraft can search and ascent take place without additional power of for instance (jet) engines being necessary for this purpose.
• the mobile platform preferably comprises a pump for pumping the separated composition to and through openings of the skin.
• the composition is gaseous or liquid.
• the openings preferably have a diameter in a range of 30 pm-l0 mm, more preferably 60 pm-500 pm.
• the skin of the mobile platform is preferably manufactured using additive manufacturing, i.e. 3D printing.
• the openings and channels for supplying the composition to the openings can hereby be arranged integrally in the skin, whereby weight can be saved.
• the separation device is preferably a membrane separation device.
• the membrane separation device more preferably comprises hollow membrane fibres.
• the membrane can be a nitrogen membrane or an oxygen membrane, whereby the retentate comprises respectively an increased concentration of oxygen or an increased
• the mobile platform preferably comprises an inlet for admitting the fluid and preferably a compressor for increasing the pressure of the admitted fluid, wherein the mobile platform is configured to supply the fluid with the increased pressure to the separation device.
• a device without compressor is possible when the inlet is formed such that, due to the relative velocity of the fluid entering the inlet, an increased pressure of the fluid being carried to the separation device is brought about.
• the compressor is for instance suitable for increasing the pressure to 5, 7 or 10 bar. Such pressures are also particularly suitable for application with a membrane separation device.
• the mobile platform is preferably an aircraft, wherein the compressor is an axial compressor. It is particularly in the case of aircraft that application of the layer via the openings can reduce both the frictional resistance and bring about a modification of the“lift” or the buoyancy. In respect of the frictional resistance, the flow profile of the fluid around the aircraft can for instance be modified. Use of components with a density differing from that of air also enables the density to be modified locally, close to the skin, whereby the frictional resistance will also change.
• the separation device is preferably configured to separate the oxygen and nitrogen.
• the composition formed by the one or more separated components preferably comprises more nitrogen than the air surrounding the aeroplane.
• the composition more preferably comprises substantially nitrogen. (Unavoidable) impurities can further occur in this composition.
• substantially nitrogen facilitates the configuration of the separation device, since mixing need no longer take place.
• the nitrogen, as retentate or as permeate, depending on the membrane used, can be carried directly from the separation device to the openings in the skin.
• the mobile platform is a vessel, wherein the fluid is water, wherein the separation device is configured to separate the fluid into water with an increased salt content and water with a reduced salt content relative to the fluid, wherein the composition is formed by the water with an increased salt content or the water with a reduced salt content.
• the present patent application provides a method for applying a composition to a skin of a mobile platform, wherein the mobile platform moves through a fluid surrounding the mobile platform, the method comprising of:
• composition differs from a composition of the fluid surrounding the mobile platform.
• Fig. 1 is a schematic side view of an aeroplane with a plurality of openings and a separation device according to a preferred embodiment
• Fig. 2 is a schematic side view of the aeroplane of Fig. 1 with the separation device in operative situation;
• Fig. 3 is a schematic view of a layer of air at a skin of an aircraft, wherein no layer is applied to the skin;
• Fig. 4 is a schematic view of a layer of air at a skin of an aircraft, wherein a layer of a composition with substantially nitrogen is applied to the skin;
• Fig. 5 is a schematic view of an aeroplane with a plurality of openings and a separation device according to a further preferred embodiment.
• An aeroplane 1 advancing in air 2 experiences frictional resistance from the relative velocity of the aeroplane 1 in relation to the air 2.
• Aeroplane 1 comprises a skin 4 with a plurality of openings 5 therein.
• Aeroplane 1 comprises a membrane separation device 3.
• Membrane separation device 3 is in gas communication connection with inlet 7.
• a layer 9 of the composition is created around aeroplane 1.
• the thickness of the layer is exaggerated and will be many times thinner in an actual embodiment.
• Fig. 3 shows a situation in which a layer of the composition has not been applied to skin 4.
• the relative movement of the air in relation to skin 4 is indicated with arrows A.
• Schematically shown is a composition of oxygen and nitrogen, wherein the oxygen is represented as a sphere with a greater diameter than a sphere designating the nitrogen.
• the crosses R indicate where a boundary layer is situated between the skin and the surrounding air.
• a layer 9 has been arranged via opening 50 of the plurality of openings 5 all around the skin 4 of the aeroplane.
• a diameter of opening 50 is indicated with the arrow d, and is for instance 100 pm.
• the boundary layer as indicated with the crosses R is now situated further away from the skin.
• the flow velocity of layer 9 will differ from that of the air originally surrounding the skin.
• layer 9 will also begin to flow along, the frictional resistance decreases.
• layer 9 comprises substantially oxygen.
• layer 9 comprises substantially nitrogen.
• Fig. 5 shows an embodiment of a system 10 with a skin 4 and membrane separation device 3.
• the system comprises an inlet 7 into which air surrounding the aeroplane flows, as indicated with arrow C.
• the admitted air is optionally compressed in compressor 11 , for instance to a pressure in a range of 4-10 bar, for instance 5, 7 or 8 bar.
• Compressor 11 can be an axial compressor.
• membrane separation device 3 comprises a plurality of hollow membrane fibres shown as single membrane 12, inside which the pressure of for instance 7 bar prevails at an inlet 13 of membrane separation device 3. A lower pressure prevails on an outer side 14 of the hollow membrane fibres. A driving force for separating the components of air is provided by the pressure difference between inner side 13 and outer side 14 of the membrane fibres.
• the components of the inlet air comprise oxygen and nitrogen, in concentrations of respectively about 21% and 78%.
• the hollow membrane fibres can have oxygen membranes or nitrogen membranes as their wall. When nitrogen membranes are used, nitrogen will be the permeate and will be discharged via the discharge 16. When oxygen membranes are used, as shown in Fig. 5, oxygen will be the permeate and nitrogen will be discharged from membrane separation device 3 as retentate. Nitrogen will be discharged from membrane separation device 3 as retentate via discharge 18. The discharge of the nitrogen can take place in controllable manner using a valve 20, for instance a controllable solenoid valve.
• the oxygen or the nitrogen, and/or other components of air, such as argon or water, are used to make a composition which is discharged to openings 5 via conduits 22.
• the composition has a composition differing from that of air.
• a composition with an increased concentration of oxygen can for instance be carried to the openings 50 of the plurality of openings 5, for instance 80% oxygen and 19-20% nitrogen.
• a mixing device can for instance be used for this purpose.
• Another option is to configure the separating device such that for instance the retentate comprises 80% oxygen, in which roughly 19-20% nitrogen has remained. It is also possible to envisage a composition of substantially oxygen or substantially nitrogen, wherein a mixing device need not be used.
• the mobile platform is an underwater vessel.
• the fluid is water and the separating device is configured to separate the fluid into water with an increased salt content and water with a reduced salt content relative to the fluid, wherein the composition is formed by the water with an increased salt content or the water with a reduced salt content.
• the buoyancy of the vessel can be modified by modification of the local salt concentration. Furthermore, spraying of the composition toward the outer side of the skin via the openings here also causes a change of the flow profile along the skin of the submersible craft, whereby a reduction in the frictional resistance can be obtained.

Landscapes

• Engineering & Computer Science (AREA)
• Aviation & Aerospace Engineering (AREA)
• Separation Using Semi-Permeable Membranes (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=60923876

Family Applications (1)

Country Status (2)

Cited By (1)

Citations (5)

• 2017
  • 2017-12-18 NL NL2020113A patent/NL2020113B1/nl active
• 2018
  • 2018-12-14 WO PCT/NL2018/050842 patent/WO2019125141A1/en active Application Filing

Patent Citations (5)

Also Published As

Similar Documents

Legal Events