WO2021069789A1 - Aerofoil with passive flow-control device - Google Patents

Aerofoil with passive flow-control device Download PDF

Info

Publication number
WO2021069789A1
WO2021069789A1 PCT/ES2020/070615 ES2020070615W WO2021069789A1 WO 2021069789 A1 WO2021069789 A1 WO 2021069789A1 ES 2020070615 W ES2020070615 W ES 2020070615W WO 2021069789 A1 WO2021069789 A1 WO 2021069789A1
Authority
WO
WIPO (PCT)
Prior art keywords
opening
fluid
control device
tubular conduit
flow control
Prior art date
Application number
PCT/ES2020/070615
Other languages
Spanish (es)
French (fr)
Inventor
Pedro Acha Gandarias
Original Assignee
Brainstorming Aviation, Sociedad Limitada
ORTIZ PACHECO, Pedro
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Brainstorming Aviation, Sociedad Limitada, ORTIZ PACHECO, Pedro filed Critical Brainstorming Aviation, Sociedad Limitada
Publication of WO2021069789A1 publication Critical patent/WO2021069789A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C21/00—Influencing air flow over aircraft surfaces by affecting boundary layer flow
    • B64C21/02—Influencing air flow over aircraft surfaces by affecting boundary layer flow by use of slot, ducts, porous areas or the like
    • B64C21/025—Influencing air flow over aircraft surfaces by affecting boundary layer flow by use of slot, ducts, porous areas or the like for simultaneous blowing and sucking
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C21/00—Influencing air flow over aircraft surfaces by affecting boundary layer flow
    • B64C21/10—Influencing air flow over aircraft surfaces by affecting boundary layer flow using other surface properties, e.g. roughness
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15D—FLUID DYNAMICS, i.e. METHODS OR MEANS FOR INFLUENCING THE FLOW OF GASES OR LIQUIDS
    • F15D1/00—Influencing flow of fluids
    • F15D1/002—Influencing flow of fluids by influencing the boundary layer
    • F15D1/0025—Influencing flow of fluids by influencing the boundary layer using passive means, i.e. without external energy supply
    • F15D1/0055—Influencing flow of fluids by influencing the boundary layer using passive means, i.e. without external energy supply comprising apertures in the surface, through which fluid is withdrawn from or injected into the flow
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C2230/00—Boundary layer controls
    • B64C2230/20—Boundary layer controls by passively inducing fluid flow, e.g. by means of a pressure difference between both ends of a slot or duct

Definitions

  • the invention relates to an aerodynamic profile comprising a passive flow control device in order to control the aerodynamic characteristics thereof.
  • the passive flow control device is of the type that acts on the boundary layer of the air that circulates adjacent to said profile in such a way as to allow the delay of the transition point from laminar flow to turbulent flow of said boundary layer and, therefore, therefore, it manages to improve the lift and the aerodynamic resistance of the profile.
  • the invention is applicable to relative speeds between the fluid and the aerodynamic profile of between 150 km / h - 350 km / h, which corresponds, among other examples, to the take-off and landing speeds of aircraft.
  • Reynolds number is understood as a dimensionless number used in fluid mechanics to characterize the movement of a fluid. Its value indicates whether the flow follows a laminar or turbulent pattern.
  • the aerodynamic profile object of the invention is of the type that comprises at least one body and an external surface of the body configured for the movement of a fluid thereon.
  • Said external surface comprises an upper surface and a lower surface, the aerodynamic control device being located on the upper surface.
  • the aerofoil could comprise more than one body, for example a main body and additional main body control bodies, such as a flap, slat or aileron of a main body or airfoil.
  • a passive flow control device is understood as a device that, by definition, does not need energy, for example electrical or mechanical.
  • the passive flow control device object of the invention comprises: • a first opening made in the body and located on the surface of the upper surface,
  • the tubular conduit located in the body and extending between the first and second openings.
  • the tubular conduit comprises: o at least a straight longitudinal section, or a constant section along its length, and or a hydraulic diameter between 5% and 30% of the distance between the first opening and the second opening, normally measured in the direction of advance of the fluid.
  • the first opening, the second opening and the tubular conduit are configured in such a way that, in operation, the speed of the fluid that moves on the extrados makes a drag of the fluid contained inside the tubular conduit through the first opening and its once the dragging of the fluid inside the tubular conduit sucks the fluid that moves on the extrados through the second opening into the tubular conduit. Therefore, the device object of the patent relates the distance between the openings and the hydraulic diameter.
  • the profile therefore has openings, a first opening or drag opening and a second opening or suction opening. That is, the fluid leaves the tubular conduit through the first opening and enters the tubular conduit through the second opening following the previous configuration of the openings and the tubular conduit.
  • the device object of the invention is a passive type device, that is, it does not require the input of external energy, electrical or mechanical, to start operating. Therefore, one of its advantages is that there is no need for any additional device that prints energy to the fluid stream emanating from the conduit. tubular as it is dragged by the fluid that circulates on the upper surface of the aerodynamic profile. Likewise, no mechanical or electrical device is necessary to suck the boundary layer through the second opening or suction opening, since it is the depression itself that causes the dragging of the fluid through the first opening in the tubular conduit. suction through the second opening.
  • the longitudinal axis of the tubular conduit will be located in a plane substantially parallel to the direction of the chord of the aerofoil.
  • the openings and the conduit do not follow the line of the rope and form an angle with it.
  • the conduit will normally be in a plane substantially parallel to the direction of the fluid, although this may not be the case.
  • the chute would form an angle to the direction of the flow. In this case, the device would also go into operation.
  • the first and second openings will normally be located in line according to the direction of advance of the fluid. Specifically, if we speak of a wing profile, they are located in the direction of the chord of said profile.
  • the duct will also normally be located according to the direction of advance of the fluid, that is, with the longitudinal axis of the tubular duct in the direction of the chord of the profile, if the exemplary embodiment corresponds to a wing profile and the duct extends according to the direction of the string.
  • Substantially parallel means that it is parallel, or it deviates a few degrees, for example, less than 15 ° deviation.
  • the aerodynamic control device comprises a first and a second opening located on the upper face or extrados of the aerodynamic profile and connected to each other by means of a tubular conduit that extends between the second opening or suction opening and the first opening or opening. drag that has certain characteristics.
  • the tubular conduit can have a circular, square, etc. section.
  • the tubular duct is located in the body of the aerodynamic profile, either the main body of the aerodynamic profile or an additional control body of said main body. Therefore, the aerodynamic control device can be located, for example, on an airfoil of an airplane, such as a wing, a HTP (horizontal tail plane) or on a slat, flap, aileron, etc., of said airfoil. . It can also be located in another type of aerodynamic profile, such as a wind turbine blade or any other element that requires an aerodynamic surface such as a turbine, a boat, etc.
  • the tubular conduit comprises a constant hydraulic diameter, without widening or narrowing and at least one straight section, that is, without curvatures.
  • A is the cross-sectional area of the tubular conduit
  • P is the wetted perimeter which, in the case of a closed conduit through which a gaseous fluid circulates, is the perimeter of the tubular conduit.
  • the hydraulic diameter of the tubular conduit is between 5% and 30% of the distance between the first opening and the second opening in the direction of advance of the fluid. If the distance between both openings were greater than the previous relation, there could be pressure losses along the tubular conduit and the suction could not occur in the second opening. If the distance were smaller than the previous ratio, the smaller pressure difference between both openings could prevent the flow of fluid from occurring and also the tubular conduit would have abrupt curvature changes that would cause head losses.
  • the speed of the air flow moving over the first opening towards the second opening that is, over the top surface, causes the fluid located in the tubular conduit to be drawn out of the tubular conduit through the first opening and, therefore, it is integrated into the boundary layer of the fluid moving over the aerodynamic surface.
  • the speed at which the air flow leaves the first opening or entrainment opening is, therefore, less than the speed of the boundary layer that runs above said opening, since said boundary layer is the one that carries out the entrainment of the volume of fluid contained in the conduit connecting both openings.
  • the air flow inside the duct has a speed lower than the speed of the boundary layer that moves on the upper face of the profile and when approaching the first opening where the drag occurs, the fluid flow inside the tubular duct increases its speed, but always staying lower than the speed of the boundary layer.
  • the air flow emanating from the first opening is not a high speed injected flow in the boundary layer, but rather a slower speed flow.
  • the Coanda effect is understood as the tendency of a jet of fluid emerging from an orifice to follow an adjacent flat or curved surface and to drag fluid from the environment so that a lower pressure region develops, whereby the fluid "follows" the body surface.
  • the device object of the Invention manages to increase the Coanda effect of the boundary layer and its adherence to the extrados, whereby the air flow follows the surface of the upper face of the profile, delaying the detachment of the boundary layer from said boundary layer. upper face or extrados.
  • the mixture between the boundary layer and the flow layer entrained from the first opening causes said boundary layer to remain glued to the upper face of the airfoil even at high angles of attack which increases the lift of the airfoil.
  • the aerodynamic profile object of the invention increases the lift force without increasing the resistance to the advance or dragging.
  • the fluid in the tubular conduit begins to move in the direction of the second to the first opening, when the speed of the aircraft reaches a Lower threshold value, the difference in speed and pressure between both openings is such that all the fluid inside the tube is dragged by the boundary layer that runs over the first opening of the upper face of the profile or extrados. Also, when a maximum threshold value of the aircraft speed is exceeded, the difference in speed and pressure between both openings is minimal and, therefore, the movement of the fluid inside the tubular conduit stops, leaving the device at cruising speeds of the aircraft, so it does not interfere with the aerodynamics of the profile at these speeds.
  • the device object of the invention comes into operation for differential speeds between the profile and the surrounding fluid between 150-350 km / h, which are the take-off and landing speeds of the aircraft, therefore, the passive aerodynamic control device will enter in action at take-off and landing moments, achieving an increase in lift and thus reducing the take-off and landing distance.
  • the aerodynamic profile object of the invention is the beginning of a line of investigation between different distances of openings, different lengths and different diameters of the duct.
  • Figures 1a and 1b show a schematic side view of a section of an aerofoil. Specifically a NACA 23012 series wing airfoil with a 25 degree angle of attack.
  • Figure 1a shows an example of an embodiment of the passive flow control device located on the upper surface and in the vicinity of the trailing edge of the wing profile and how it affects the distribution of the flow lines at an approximate speed of 250 km / h. h.
  • Figure 1b shows the same wing profile as figure 1a without the passive flow control device and the distribution of the flow lines at the same speed. Comparing both figures shows how the device achieves the delay of the transition point of the boundary layer.
  • Figures 2a and 2b show a schematic side view of a section of an aerofoil. As in Figures 1a and 1b, it corresponds to a NACA 23012 series wing profile but with an angle of attack of 35 degrees.
  • Figure 2a shows an exemplary embodiment of the flow control device located in the vicinity of the leading edge of the wing profile and how it affects the distribution of the flow lines at a speed of approximately 250 km / h.
  • Figure 2a shows said wing profile without the passive flow control device and the distribution of the flow lines at the same speed. From the comparison of Figures 2a and 2b, it is seen how the device achieves the delay of the transition point of the boundary layer.
  • Figures 3a and 3b show a side view of a section of the aerodynamic profile corresponding to Figures 2a and 2b with the same angle of attack, and with a slat in the deployed position.
  • Figure 4 shows a schematic longitudinal section of an embodiment of the tubular duct and the openings of the aerodynamic control device.
  • Figure 5 shows an enlargement of the first opening of the tubular conduit corresponding to figure 4.
  • the exemplary embodiment of the attached figures corresponds to a NACA 23012 series wing profile.
  • Said profile comprises an upper or upper face (20) and a lower or intrados face (21), a leading edge (22) and an edge of outlet (23) located downstream of the leading edge (22).
  • the passive flow control device is located on the top surface (20).
  • the passive control device of said exemplary embodiment comprises:
  • the tubular conduit (3) located inside the body (24) of the aerofoil and extending between the first (1) and the second (2) openings.
  • the tubular conduit (3) has its longitudinal axis in a plane parallel to the direction of advance of the fluid.
  • the tubular conduit (3) comprises a constant section and at least one straight section (3.1).
  • the hydraulic diameter is between 5% and 30% of the distance between the first opening (1) and the second opening (2) in the direction of advance of the fluid.
  • the hydraulic diameter of the tubular conduit (3) will be between 10% and 20% of the distance between the first opening (1) and the second opening (2) in the direction of advance of the fluid or of the rope for a optimal device performance. More preferably, the hydraulic diameter of the tubular conduit (3) will be between 12% and 17% of the distance between the first opening (1) and the second opening (2).
  • the aerodynamic profile comprising the passive device object of the invention delays the transition point at which the boundary layer passes from a laminar to turbulent regime at a speed of approximately 250 km / h.
  • chord of the profile is approximately 1 m and the flight conditions are modeled on different angles of attack common to the takeoff and landing maneuvers of an aircraft.
  • the first opening (1) is configured so that the ratio of forces C ⁇ between the air flow leaving the opening (1) and the air flow of the fluid sliding over the upper surface (20) in the vicinity of the opening (1) is between 0.10 and 0.25 according to: where, is the coefficient of moments, is the mass flow of the fluid that leaves the tubular conduit (3) through the opening (1),
  • V 1 is the velocity of the fluid that leaves the tubular conduit (3) through the opening (1), where V 1 is the density of the fluid that slides on the upper surface (20) is the speed of the fluid that slides on the upper surface (20)
  • A is the area of the tubular conduit (3)
  • p 1 is the density of the fluid that leaves the tubular conduit (3) through the opening
  • a 1 is the area of the tubular duct (3) ⁇ 1 the angle between the longitudinal axis of the tubular duct (3) in the section of the first opening (1) with the plane of the extrados (20), the angle measured from the plane of the extrados (20) towards the longitudinal axis of the tubular duct (3) in the anticlockwise direction.
  • the force ratio C ⁇ between the air flow leaving the opening (1) and the air flow of the fluid sliding on the extrados (20) in the vicinity of the opening (1) will be 0.17.
  • Figures 4 and 5 schematically represent the details of the tubular conduit (3) comprising a straight section (3.2), a first curved section (3.1) that extends between the first opening (1) and the straight section (3.2) and a second curved section (3.3) that extends between the straight section (3.2) and the second opening (2).
  • the longitudinal axis forms an angle of less than 30o with the plane of the extrados (20) measured from the plane from the surface (30) towards the longitudinal axis in the counterclockwise direction.
  • the first opening (1) or trailing opening is preferably tangent or almost tangent to the extrados (20) of the aerodynamic profile.
  • This has the advantage that the direction of the entrained air flow is mixed in the same direction of advance of the boundary layer. If it were done with an angle greater than 30o with respect to the extrados (20), a separation of the boundary layer could occur due to the direction of the entrained flow, thus increasing the thickness of the boundary layer.
  • said angle is preferably 13 °.
  • the longitudinal axis of the tubular conduit (3) in the second curved section (3.3) in the section of the second opening (1) forms an angle of around 90 ° with the plane of the surface (30).
  • the angle between the longitudinal axis of the tubular conduit (3) in the section of the second opening (2) and the longitudinal axis of the tubular conduit (3) in the straight section (3.2) is greater than 90 ° .
  • the longitudinal axis of the straight section (3.2) is not parallel to the surface of the extrados (20).
  • the tubular conduit (3) takes advantage of the smooth curvature to generate a smooth speed drop. Slightly curved sections in closed sections, help the mixing of the velocity vectors within it and the flow current inside the conduit to remain close to the laminar regime. This means a gradual slowdown of the internal velocity of the duct, better to remain in a laminar regime within closed ducts. Additionally, the coefficient of air moments when mixing streams in a laminar regime achieves a better result.
  • the distance between the first opening (1) and the second opening (2) is between 15% and 25% of the chord length of the aerofoil, preferably between 18% and 20%.
  • the tubular conduit (3) and both openings (1, 2) have the same section of 0.00045 m 2 and there is a pressure difference between both openings (1, 2) of 6 mmHg, the first opening (1) having a pressure of 750.7 mmHg and the second opening (2) having a pressure of 756.7 mmHg for an angle of attack of 26o for a NACA 23012 series wing profile and a wing chord length of 1 m, the temperature being 20 oC, the dynamic air density of 0.01682 mPa * s and the speed of 250 km / h with a Reynolds number of 4,900,000, that is, in the case of laminar-turbulent transitional regime study . Under these conditions, the speed at which the volume of fluid contained in the tubular conduit (3) leaves the first opening (1) is 72 km / h while the surrounding fluid over the second opening (2) has a speed of 277 km / h.
  • the aerodynamic profile comprises a set of tubular ducts (3) and first and second openings (1, 2), said tubular ducts (3) and their corresponding openings (1, 2) being located aligned in the direction advancement of the fluid, so that the openings (1, 2) are aligned one behind the other in the direction of advance of the fluid. In this way, they act in a cascade on the boundary layer, delaying its separation from the aerodynamic surface.
  • the openings (1, 2) would be located in line according to the chord of the same.
  • the openings (1, 2) could be located in a matrix manner on the surface, that is, not only in the direction of advance of the fluid, but also in the direction perpendicular to the advance of the fluid.
  • each passive device would occupy approximately an area of 0.0104 m 2 .
  • the surface occupied by them would be 11.94 m 2 . Therefore, the number of ducts (3) and openings (1, 2) that could be implemented in a wing of a single-aisle type aircraft would be 1148 units arranged, for example, in a matrix.
  • the exemplary embodiment is again used with the boundary conditions set forth above, that is, for a wing profile of the NACA 23012 series, in a situation of take-off for an angle of attack of 26o, free air flow speed of 250 km / h, dynamic air density of 0.01682 mPa * s, being the ambient temperature of 20 oC, with a Reynolds number of 4900000, is that is, in the case of study of the laminar-turbulent transitional regime.
  • a NACA23012 profile without the passive lifting device object of the invention has a total lift of 518.8 Newton, while the same NACA23012 profile with a device according to the object of the invention has a total lift of 553.5 Newton, that is, a variation of the lift force of 34.7 Newton.
  • the equivalence for units in kilograms is 3.47 Kg of lift force exerted by one of the passive lift devices object of the invention.
  • the surface of the aerodynamic profile located between the first opening (1) and the second opening (2) can be rough, which helps to delay the transition point from laminar to turbulent of the boundary layer.
  • the surface of the tubular conduit (3) can also be rough, with a surface finish of roughness class (Ra) from N7 to N12, according to the UNE 1037 standard. In this way, the existence of a laminar flow within the tubular conduit (3).
  • Ra roughness class

Landscapes

  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Pipe Accessories (AREA)

Abstract

The invention relates to an aerofoil with a passive flow-control device, which comprises: a first opening (1); a second opening (2) downstream of the first opening; and a tubular conduit (3) extending between the first opening (1) and the second opening (2), which has a straight longitudinal portion (3.2), a constant cross-section and a hydraulic diameter between 5 and 30% of the distance between the openings (1, 2), such that the speed of the fluid moving over the upper surface (20) pulls the fluid that is inside the tubular conduit (3) through the first opening (1), the pull of the fluid inside the tubular conduit (3) sucking the fluid moving over the second opening (2) into the tubular conduit (3).

Description

Perfil aerodinámico con dispositivo pasivo de control de flujo Aerodynamic profile with passive flow control device
Campo de la invención Field of the invention
La invención es relativa a un perfil aerodinámico que comprende un dispositivo pasivo para el control de flujo con el objeto de controlar las características aerodinámicas del mismo. Más particularmente, el dispositivo pasivo de control de flujo es del tipo que actúa sobre la capa límite del aire que circula adyacente a dicho perfil de modo que permite el retraso del punto de transición de flujo laminar a flujo turbulento de dicha capa límite y, por lo tanto, logra mejorar la sustentación y la resistencia aerodinámica del perfil. La invención tiene aplicación para velocidades relativas entre el fluido y el perfil aerodinámico de entre 150 km/h - 350 km/h, que se corresponde, entre otros ejemplos, con las velocidades de despegue y aterrizaje de aeronaves. The invention relates to an aerodynamic profile comprising a passive flow control device in order to control the aerodynamic characteristics thereof. More particularly, the passive flow control device is of the type that acts on the boundary layer of the air that circulates adjacent to said profile in such a way as to allow the delay of the transition point from laminar flow to turbulent flow of said boundary layer and, therefore, therefore, it manages to improve the lift and the aerodynamic resistance of the profile. The invention is applicable to relative speeds between the fluid and the aerodynamic profile of between 150 km / h - 350 km / h, which corresponds, among other examples, to the take-off and landing speeds of aircraft.
Estado de la técnica State of the art
Se entiende en el estado de la técnica por número de Reynolds como un número adimensional utilizado en mecánica de fluidos para caracterizar el movimiento de un fluido. Su valor indica si el flujo sigue un modelo laminar o turbulento. In the state of the art, Reynolds number is understood as a dimensionless number used in fluid mechanics to characterize the movement of a fluid. Its value indicates whether the flow follows a laminar or turbulent pattern.
En números de Reynolds altos, que indican tendencia a la turbulencia, típicos de aeronaves, es deseable tener una capa límite de tipo laminar lo que resulta, por ejemplo, en una menor fricción entre el revestimiento de la aeronave y el aire. Sin embargo, la capa límite inevitablemente se engrosa y se vuelve menos estable a medida que el flujo se desarrolla a lo largo de la superficie del revestimiento, y en un punto llamado de transición, la capa límite se transforma en turbulenta. At high Reynolds numbers, which indicate a tendency to turbulence, typical of aircraft, it is desirable to have a laminar-type boundary layer which results, for example, in less friction between the aircraft skin and the air. However, the boundary layer inevitably thickens and becomes less stable as the flow develops along the surface of the coating, and at a so-called transition point, the boundary layer becomes turbulent.
Es conocido y deseado retrasar dicha transición de un flujo de aire laminar a turbulento a lo largo de una superficie. Por ejemplo, es conocido en el estado de la técnica el aplicar este control de dicha transición con elementos de sustentación de una aeronave, retrasando la separación de la capa límite y logrando una distribución favorable de la presión a lo largo de la superficie de dichos elementos de control, lo que resulta en una mejor sustentación y una menor resistencia aerodinámica de la superficie. Para ello, es conocido proporcionar un flujo de aire a la superficie superior del perfil aerodinámico, o extradós, cercano al borde de ataque, en la zona de la capa límite, a través de un conducto que se dispone en conexión con un elemento que imprime presión positiva de empuje al mencionado flujo de aire de dicho conducto, por ejemplo, una bomba mecánica o eléctrica. De este modo se inyecta fluido en la capa límite, a mayor velocidad que la propia capa límite, a través de unas aberturas en la superficie del perfil aerodinámico y de este modo se logra el retraso de la separación de la capa límite. It is known and desired to delay such a transition from laminar to turbulent air flow along a surface. For example, it is known in the state of the art to apply this control of said transition with support elements of an aircraft, delaying the separation of the boundary layer and achieving a favorable pressure distribution along the surface of said elements. control, resulting in better lift and lower surface drag. For this, it is known to provide an air flow to the upper surface of the aerodynamic profile, or extrados, close to the leading edge, in the area of the boundary layer, through a duct that is arranged in connection with a printing element. positive push pressure to said air flow of said conduit, for example, a mechanical or electric pump. In this way, fluid is injected into the boundary layer, at a higher speed than the boundary layer itself, through openings in the surface of the aerodynamic profile and in this way delaying the separation of the boundary layer is achieved.
Es también conocido aspirar la capa límite del extradós con un elemento que imprime presión negativa de aspiración, por ejemplo, una bomba mecánica o eléctrica, a través de, por ejemplo, una superficie porosa. Sin embargo, por lo general, esta realización no puede llevarse a la práctica debido a su complejidad mecánica y a la potencia necesaria para la aspiración del aire y su posterior eliminación. It is also known to suck the boundary layer of the extrados with an element that produces negative suction pressure, for example a mechanical or electric pump, through, for example, a porous surface. However, in general, this embodiment cannot be implemented due to its mechanical complexity and the power required for suction of air and its subsequent removal.
Específicamente, es conocido el intento de comunicar una abertura en el borde de ataque con una abertura en el borde de salida, pero sin éxito debido a las pérdidas de carga existentes en el conducto de conexión. Specifically, it is known to attempt to communicate an opening in the leading edge with an opening in the trailing edge, but without success due to the pressure losses existing in the connecting conduit.
Sumario de la invención Summary of the invention
El perfil aerodinámico objeto de la invención es del tipo que comprende al menos un cuerpo y una superficie externa del cuerpo configurada para el desplazamiento de un fluido sobre la misma. Dicha superficie externa comprende un extradós y un intradós, estando localizado el dispositivo de control aerodinámico en el extradós. The aerodynamic profile object of the invention is of the type that comprises at least one body and an external surface of the body configured for the movement of a fluid thereon. Said external surface comprises an upper surface and a lower surface, the aerodynamic control device being located on the upper surface.
El perfil aerodinámico podría comprender más de un cuerpo, por ejemplo, un cuerpo principal y cuerpos adicionales de control del cuerpo principal, como, por ejemplo, un flap, un slat o un alerón de un cuerpo principal o superficie sustentadora. The aerofoil could comprise more than one body, for example a main body and additional main body control bodies, such as a flap, slat or aileron of a main body or airfoil.
Se entiende por dispositivo pasivo de control de flujo, un dispositivo que, por definición, no necesita energía, por ejemplo, eléctrica o mecánica. A passive flow control device is understood as a device that, by definition, does not need energy, for example electrical or mechanical.
El dispositivo pasivo de control de flujo objeto de la invención comprende: • una primera abertura realizada en el cuerpo y localizada en la superficie del extradós, The passive flow control device object of the invention comprises: • a first opening made in the body and located on the surface of the upper surface,
• una segunda abertura realizada en el cuerpo y localizada en la superficie del extradós, aguas abajo de la primera abertura, respecto de la dirección de avance del fluido, • a second opening made in the body and located on the surface of the extrados, downstream of the first opening, with respect to the direction of advance of the fluid,
• un conducto tubular localizado en el cuerpo y que se extiende entre la primera y la segunda aberturas. El conducto tubular comprende: o al menos un tramo longitudinal recto, o una sección constante a lo largo de su longitud, y o un diámetro hidráulico entre un 5% y un 30% de la distancia entre la primera abertura y la segunda abertura, normalmente medida en la dirección de avance del fluido. • a tubular conduit located in the body and extending between the first and second openings. The tubular conduit comprises: o at least a straight longitudinal section, or a constant section along its length, and or a hydraulic diameter between 5% and 30% of the distance between the first opening and the second opening, normally measured in the direction of advance of the fluid.
La primera abertura, la segunda abertura y el conducto tubular están configurados de modo que, en funcionamiento, la velocidad del fluido que se desplaza sobre el extradós realiza un arrastre del fluido contenido en el Interior del conducto tubular a través de la primera abertura y a su vez el arrastre del fluido del interior del conducto tubular realiza una succión del fluido que se desplaza sobre el extradós a través de la segunda abertura hacia el conducto tubular. Por lo tanto, el dispositivo objeto de la patente relaciona la distancia entre las aberturas y el diámetro hidráulico. El perfil, por lo tanto, posee sendas aberturas, una primera abertura o abertura de arrastre y una segunda abertura o abertura de succión. Es decir, el fluido sale del conducto tubular por la primera abertura y entra en el conducto tubular por la segunda abertura siguiendo la anterior configuración de las aberturas y el conducto tubular. The first opening, the second opening and the tubular conduit are configured in such a way that, in operation, the speed of the fluid that moves on the extrados makes a drag of the fluid contained inside the tubular conduit through the first opening and its once the dragging of the fluid inside the tubular conduit sucks the fluid that moves on the extrados through the second opening into the tubular conduit. Therefore, the device object of the patent relates the distance between the openings and the hydraulic diameter. The profile therefore has openings, a first opening or drag opening and a second opening or suction opening. That is, the fluid leaves the tubular conduit through the first opening and enters the tubular conduit through the second opening following the previous configuration of the openings and the tubular conduit.
Según lo comentado anteriormente, el dispositivo objeto de la invención es un dispositivo de tipo pasivo, es decir, no requiere aporte de energía externa, eléctrica o mecánica, para entrar en funcionamiento. Por lo tanto, una sus ventajas es que no hay necesidad de ningún dispositivo adicional que imprima energía a la corriente de fluido que emana del conducto tubular ya que es arrastrada por el fluido que circula sobre el extradós del perfil aerodinámico. Igualmente, tampoco es necesario ningún dispositivo mecánico o eléctrico que succione la capa límite a través de la segunda abertura o abertura de succión, ya que es la propia depresión que causa en el conducto tubular el arrastre del fluido a través de la primera abertura la que realiza la succión a través de la segunda abertura. As discussed above, the device object of the invention is a passive type device, that is, it does not require the input of external energy, electrical or mechanical, to start operating. Therefore, one of its advantages is that there is no need for any additional device that prints energy to the fluid stream emanating from the conduit. tubular as it is dragged by the fluid that circulates on the upper surface of the aerodynamic profile. Likewise, no mechanical or electrical device is necessary to suck the boundary layer through the second opening or suction opening, since it is the depression itself that causes the dragging of the fluid through the first opening in the tubular conduit. suction through the second opening.
En un ejemplo de realización, el eje longitudinal del conducto tubular estará localizado en un plano sustancialmente paralelo a la dirección de la cuerda del perfil aerodinámico. Otras realizaciones son posibles, por ejemplo, que las aberturas y el conducto no sigan la línea de la cuerda y formen un ángulo con la misma. En funcionamiento, normalmente el conducto estará en un plano sustancialmente paralelo a la dirección del fluido, aunque es posible que esto no sea así. Por ejemplo, en una maniobra de aterrizaje con viento cruzado, donde el conducto formaría un ángulo respecto a la dirección del fluido. En este caso, el dispositivo también entraría en funcionamiento. In an exemplary embodiment, the longitudinal axis of the tubular conduit will be located in a plane substantially parallel to the direction of the chord of the aerofoil. Other embodiments are possible, for example, that the openings and the conduit do not follow the line of the rope and form an angle with it. In operation, the conduit will normally be in a plane substantially parallel to the direction of the fluid, although this may not be the case. For example, in a crosswind landing maneuver, where the chute would form an angle to the direction of the flow. In this case, the device would also go into operation.
Según lo anterior, la primera y la segunda aberturas se localizarán, normalmente, en línea según la dirección de avance del fluido. Específicamente, si hablamos de un perfil alar se localizan en la dirección de la cuerda de dicho perfil. El conducto también se localizará normalmente según la dirección de avance del fluido, es decir, con el eje longitudinal del conducto tubular en la dirección de la cuerda del perfil, si el ejemplo de realización se corresponde con un perfil alar y el conducto se extiende según la dirección de la cuerda. Sustancialmente paralelo significa que es paralelo, o bien, se desvía unos grados, por ejemplo, menos de 15º de desviación. Aunque según lo comentado, si el eje longitudinal del conducto del dispositivo formara un ángulo con la cuerda del perfil o con la dirección de avance del fluido, por ejemplo, de 30º, el dispositivo también entraría en funcionamiento. According to the above, the first and second openings will normally be located in line according to the direction of advance of the fluid. Specifically, if we speak of a wing profile, they are located in the direction of the chord of said profile. The duct will also normally be located according to the direction of advance of the fluid, that is, with the longitudinal axis of the tubular duct in the direction of the chord of the profile, if the exemplary embodiment corresponds to a wing profile and the duct extends according to the direction of the string. Substantially parallel means that it is parallel, or it deviates a few degrees, for example, less than 15 ° deviation. Although as commented, if the longitudinal axis of the device conduit were at an angle with the chord of the profile or with the direction of advance of the fluid, for example, 30 °, the device would also come into operation.
En definitiva, el dispositivo de control aerodinámico comprende una primera y una segunda abertura localizadas en la cara superior o extradós del perfil aerodinámico y conectadas entre sí mediante un conducto tubular que se extiende entre la segunda abertura o abertura de succión y la primera abertura o abertura de arrastre que presenta unas características determinadas. Ultimately, the aerodynamic control device comprises a first and a second opening located on the upper face or extrados of the aerodynamic profile and connected to each other by means of a tubular conduit that extends between the second opening or suction opening and the first opening or opening. drag that has certain characteristics.
El conducto tubular puede tener una sección circular, cuadrada, etc. El conducto tubular se localiza en el cuerpo del perfil aerodinámico, bien sea este el cuerpo principal del perfil aerodinámico o un cuerpo adicional de control de dicho cuerpo principal. Por lo tanto, el dispositivo de control aerodinámico se puede localizar, por ejemplo, en una superficie sustentadora de un avión, como un ala, un HTP (horizontal tail plañe) o en un slat, flap, alerón, etc, de dicha superficie sustentadora. Igualmente puede estar localizado en otro tipo de perfil aerodinámico, como una pala de un aerogenerador o cualquier otro elemento que requiera de una superficie aerodinámica tal como una turbina, una embarcación, etc. The tubular conduit can have a circular, square, etc. section. The tubular duct is located in the body of the aerodynamic profile, either the main body of the aerodynamic profile or an additional control body of said main body. Therefore, the aerodynamic control device can be located, for example, on an airfoil of an airplane, such as a wing, a HTP (horizontal tail plane) or on a slat, flap, aileron, etc., of said airfoil. . It can also be located in another type of aerodynamic profile, such as a wind turbine blade or any other element that requires an aerodynamic surface such as a turbine, a boat, etc.
El conducto tubular comprende un diámetro hidráulico constante, sin ensanchamientos, ni estrechamientos y al menos un tramo recto, es decir, sin curvaturas. The tubular conduit comprises a constant hydraulic diameter, without widening or narrowing and at least one straight section, that is, without curvatures.
Se entiende por diámetro hidráulico, Dh = 4A/P donde A es el área de la sección transversal del conducto tubular y P es el perímetro mojado que, en el caso de un conducto cerrado por el que circula un fluido gaseoso, es el perímetro del conducto tubular. Por ejemplo, para un conducto cilindrico de sección circular es el mismo diámetro de la sección circular y para un conducto de sección rectangular sería [4 * (largo x alto)] / [2 * (largo + alto)]. Hydraulic diameter is understood as D h = 4A / P where A is the cross-sectional area of the tubular conduit and P is the wetted perimeter which, in the case of a closed conduit through which a gaseous fluid circulates, is the perimeter of the tubular conduit. For example, for a cylindrical pipe with a circular section it is the same diameter as the circular section and for a pipe with a rectangular section it would be [4 * (length x height)] / [2 * (length + height)].
El diámetro hidráulico del conducto tubular está entre un 5% y un 30% de la distancia entre la primera abertura y la segunda abertura en la dirección de avance del fluido. Si la distancia entre ambas aberturas fuera mayor que la anterior relación, podrían existir pérdidas de carga a lo largo del conducto tubular y no podría no producirse la succión en la segunda abertura. Si la distancia fuera menor que la anterior relación, la menor diferencia de presión entre ambas aberturas podría impedir que se produzca el flujo de fluido y además el conducto tubular tendría cambios de curvatura abruptos que provocarían pérdidas de carga. La velocidad del flujo de aire que se desplaza sobre la primera abertura hacia la segunda abertura, es decir, sobre el extradós, hace que el fluido localizado en el conducto tubular sea arrastrado hacia el exterior del conducto tubular a través de la primera abertura y, por lo tanto, se integre en la capa límite del fluido que se desplaza sobre la superficie aerodinámica. Esto provoca una caída de presión en la primera abertura lo que tiene como consecuencia el mencionado "arrastre" de fluido que se encuentra en el conducto tubular. Esta caída de presión se transmite a lo largo del fluido que se localiza en el interior del conducto tubular en la dirección hacia la segunda abertura con lo que la presión se reduce localmente en una región alrededor de la segunda abertura lo que provoca la succión de la capa límite a través de la misma. The hydraulic diameter of the tubular conduit is between 5% and 30% of the distance between the first opening and the second opening in the direction of advance of the fluid. If the distance between both openings were greater than the previous relation, there could be pressure losses along the tubular conduit and the suction could not occur in the second opening. If the distance were smaller than the previous ratio, the smaller pressure difference between both openings could prevent the flow of fluid from occurring and also the tubular conduit would have abrupt curvature changes that would cause head losses. The speed of the air flow moving over the first opening towards the second opening, that is, over the top surface, causes the fluid located in the tubular conduit to be drawn out of the tubular conduit through the first opening and, therefore, it is integrated into the boundary layer of the fluid moving over the aerodynamic surface. This causes a pressure drop in the first opening which results in the aforementioned "drag" of fluid found in the tubular conduit. This pressure drop is transmitted along the fluid that is located inside the tubular conduit in the direction towards the second opening, thereby reducing the pressure. locally in a region around the second opening which causes the boundary layer to suck through it.
La velocidad a la que el flujo de aire abandona la primera abertura o abertura de arrastre es, por lo tanto, menor que la velocidad de la capa límite que discurre por encima de dicha abertura, ya que dicha capa límite es la que realiza el arrastre del volumen de fluido contenido en el conducto que conecta ambas aberturas. El flujo de aire en el Interior del conducto posee una velocidad menor que la velocidad de la capa límite que se desplaza sobre la cara superior del perfil y al acercarse a la primera abertura donde se produce el arrastre, el flujo de fluido dentro del conducto tubular aumenta su velocidad, pero siempre manteniéndose Inferior a la velocidad de la capa límite. The speed at which the air flow leaves the first opening or entrainment opening is, therefore, less than the speed of the boundary layer that runs above said opening, since said boundary layer is the one that carries out the entrainment of the volume of fluid contained in the conduit connecting both openings. The air flow inside the duct has a speed lower than the speed of the boundary layer that moves on the upper face of the profile and when approaching the first opening where the drag occurs, the fluid flow inside the tubular duct increases its speed, but always staying lower than the speed of the boundary layer.
Es destacadle que el flujo de aire que emana de la primera abertura no es un flujo Inyectado a alta velocidad en la capa límite, sino que es un flujo a menor velocidad. It should be noted that the air flow emanating from the first opening is not a high speed injected flow in the boundary layer, but rather a slower speed flow.
La Inyección de fluido a baja velocidad desde la primera abertura logra mejorar el efecto Coanda. Se entiende por efecto Coanda como la tendencia de un chorro de fluido que emerge de un orificio a seguir una superficie plana o curva adyacente y a arrastrar fluido del entorno de modo que se desarrolle una reglón de menor presión con lo que el fluido “sigue” la superficie del cuerpo. De este modo, el dispositivo objeto de la Invención logra aumentar el efecto Coanda de la capa límite y su adherencia al extradós, por el cual el flujo de aire sigue la superficie de la cara superior del perfil retrasando el despegue de la capa límite de dicha cara superior o extradós. Low speed fluid injection from the first opening improves the Coanda effect. The Coanda effect is understood as the tendency of a jet of fluid emerging from an orifice to follow an adjacent flat or curved surface and to drag fluid from the environment so that a lower pressure region develops, whereby the fluid "follows" the body surface. In this way, the device object of the Invention manages to increase the Coanda effect of the boundary layer and its adherence to the extrados, whereby the air flow follows the surface of the upper face of the profile, delaying the detachment of the boundary layer from said boundary layer. upper face or extrados.
La mezcla entre la capa límite y la capa de flujo arrastrada desde la primera abertura hace que dicha capa límite permanezca pegada a la cara superior del perfil aerodinámico Incluso a altos ángulos de ataque lo que aumenta la sustentación del perfil aerodinámico. El perfil aerodinámico objeto de la invención incrementa la fuerza de sustentación sin Incrementar la resistencia al avance o dragging. The mixture between the boundary layer and the flow layer entrained from the first opening causes said boundary layer to remain glued to the upper face of the airfoil even at high angles of attack which increases the lift of the airfoil. The aerodynamic profile object of the invention increases the lift force without increasing the resistance to the advance or dragging.
En la segunda abertura se produce una succión y el espacio de aire que ha dejado de ocupar el aire succionado hacia dentro del conducto, es ocupado de nuevo, lo que permite una reducción del espesor de la capa límite en las Inmediaciones de la segunda abertura y aumento del efecto Coanda también aguas abajo de la segunda abertura debido a esa succión. En cierto modo se genera un flujo de aire continuo entre la primera abertura y la segunda abertura, ya que aproximadamente el flujo de aire que sale del conducto tubular es el mismo que el entra en dicho conducto por la abertura de succión. La recirculación se mantiene debido a la relativamente alta presión en la segunda abertura y la relativa baja presión en la primera abertura debido a la alta velocidad del aire que pasa sobre la primera abertura y la relativa baja velocidad en la segunda abertura según el efecto anteriormente explicado. In the second opening a suction is produced and the air space that has stopped occupying the air sucked into the duct, is occupied again, which allows a reduction in the thickness of the boundary layer in the vicinity of the second opening and increased Coanda effect also downstream of the second opening due to this suction. In a way, a continuous air flow is generated between the first opening and the second opening, since approximately the flow of air leaving the tubular conduit is the same as that entering said conduit through the suction opening. Recirculation is maintained due to the relatively high pressure in the second opening and the relative low pressure in the first opening due to the high speed of the air passing over the first opening and the relatively low speed in the second opening according to the effect explained above. .
En el caso específico de una superficie sustentadora de una aeronave, a medida que dicha aeronave aumenta su velocidad en el borde de ataque del extradós, el fluido en el conducto tubular empieza a moverse en dirección de la segunda a la primera abertura, cuando la velocidad de la aeronave llega a un valor umbral Inferior, la diferencia de velocidad y de presión entre ambas aberturas es tal que la totalidad del fluido del interior del tubo es arrastrado por la capa límite que discurre sobre la primera abertura de la cara superior del perfil o extradós. También, cuando se sobrepasa un valor umbral máximo de la velocidad de la aeronave, la diferencia de velocidad y presión entre ambas aberturas es mínima y, por lo tanto, deja de producirse el movimiento del fluido en el Interior del conducto tubular, quedando inactivo el dispositivo a velocidades de crucero de la aeronave, por lo que no interfiere en la aerodinámica del perfil a dichas velocidades. In the specific case of an airfoil of an aircraft, as said aircraft increases its speed at the leading edge of the extrados, the fluid in the tubular conduit begins to move in the direction of the second to the first opening, when the speed of the aircraft reaches a Lower threshold value, the difference in speed and pressure between both openings is such that all the fluid inside the tube is dragged by the boundary layer that runs over the first opening of the upper face of the profile or extrados. Also, when a maximum threshold value of the aircraft speed is exceeded, the difference in speed and pressure between both openings is minimal and, therefore, the movement of the fluid inside the tubular conduit stops, leaving the device at cruising speeds of the aircraft, so it does not interfere with the aerodynamics of the profile at these speeds.
El dispositivo objeto de la Invención entra en funcionamiento para velocidades diferenciales entre el perfil y el fluido circundante entre 150-350 km/h, que son las velocidades de despegue y aterrizaje de las aeronaves, por lo que, el dispositivo pasivo de control aerodinámico entrará en acción en los momentos de despegue y aterrizaje, logrando un aumento de la sustentación y reduciendo así la distancia de despegue y aterrizaje. The device object of the invention comes into operation for differential speeds between the profile and the surrounding fluid between 150-350 km / h, which are the take-off and landing speeds of the aircraft, therefore, the passive aerodynamic control device will enter in action at take-off and landing moments, achieving an increase in lift and thus reducing the take-off and landing distance.
El dispositivo objeto de la Invención posee las siguientes ventajas: The device object of the invention has the following advantages:
Reducción del consumo de combustible. Reduction of fuel consumption.
Aumento de la seguridad en el rango de velocidades críticas de despegue y aterrizaje. Increased safety in the range of critical takeoff and landing speeds.
Aumento de la carga útil que puede portar el avión. Increase in the payload that the aircraft can carry.
Disminución de la superficie alar necesaria. Todo lo anterior sin aumento de la resistencia al aire o dragging. Decreased wing area required. All of the above without increasing air resistance or dragging.
Según los anterior, el perfil aerodinámico objeto de la invención es el principio de una línea de investigación entre diferentes distancias de aberturas, diferentes longitudes y diferentes diámetros del conducto. Descripción de las figuras According to the foregoing, the aerodynamic profile object of the invention is the beginning of a line of investigation between different distances of openings, different lengths and different diameters of the duct. Description of the figures
Para completar la descripción y con el fin de proporcionar una mejor comprensión de la invención, se proporcionan unas figuras. Dichas figuras forman una parte integral de la descripción e ilustran un ejemplo de realización de la invención. To complete the description and in order to provide a better understanding of the invention, figures are provided. Said figures form an integral part of the description and illustrate an embodiment of the invention.
Las figuras 1a y 1b muestran una vista lateral esquemática de una sección de un perfil aerodinámico. Específicamente un perfil alar serie NACA 23012 con un ángulo de ataque de 25 grados. La figura 1 a muestra un ejemplo de realización del dispositivo pasivo de control de flujo situado en el extradós y en la proximidad del borde de salida del perfil alar y cómo afecta a la distribución de las líneas de flujo a una velocidad aproximada de 250 km/h. La figura 1b muestra el mismo perfil alar que la figura 1a sin el dispositivo pasivo de control de flujo y la distribución de las líneas de flujo a la misma velocidad. De la comparación de ambas figuras se aprecia cómo el dispositivo logra el retraso del punto de transición de la capa límite. Figures 1a and 1b show a schematic side view of a section of an aerofoil. Specifically a NACA 23012 series wing airfoil with a 25 degree angle of attack. Figure 1a shows an example of an embodiment of the passive flow control device located on the upper surface and in the vicinity of the trailing edge of the wing profile and how it affects the distribution of the flow lines at an approximate speed of 250 km / h. h. Figure 1b shows the same wing profile as figure 1a without the passive flow control device and the distribution of the flow lines at the same speed. Comparing both figures shows how the device achieves the delay of the transition point of the boundary layer.
Las figuras 2a y 2b muestran una vista lateral esquemática de una sección de un perfil aerodinámico. Al igual que en las figuras 1a y 1b se corresponde con un perfil alar serie NACA 23012 pero con un ángulo de ataque de 35 grados. La figura 2a muestra un ejemplo de realización del dispositivo de control de flujo situado en la proximidad del borde de ataque del perfil alar y cómo afecta a la distribución de las líneas de flujo a una velocidad aproximada de 250 km/h. La figura 2a muestra dicho perfil alar sin el dispositivo pasivo de control de flujo y la distribución de las líneas de flujo a la misma velocidad. De la comparación de las figuras 2a y 2b se aprecia cómo el dispositivo logra el retraso del punto de transición de la capa límite. Figures 2a and 2b show a schematic side view of a section of an aerofoil. As in Figures 1a and 1b, it corresponds to a NACA 23012 series wing profile but with an angle of attack of 35 degrees. Figure 2a shows an exemplary embodiment of the flow control device located in the vicinity of the leading edge of the wing profile and how it affects the distribution of the flow lines at a speed of approximately 250 km / h. Figure 2a shows said wing profile without the passive flow control device and the distribution of the flow lines at the same speed. From the comparison of Figures 2a and 2b, it is seen how the device achieves the delay of the transition point of the boundary layer.
Las figuras 3a y 3b muestran una vista lateral de una sección del perfil aerodinámico correspondiente a las figuras 2a y 2b con el mismo ángulo de ataque, y con un slat en posición desplegado. La figura 4 muestra una sección longitudinal esquemática de un ejemplo de realización del conducto tubular y de las aberturas del dispositivo de control aerodinámico. Figures 3a and 3b show a side view of a section of the aerodynamic profile corresponding to Figures 2a and 2b with the same angle of attack, and with a slat in the deployed position. Figure 4 shows a schematic longitudinal section of an embodiment of the tubular duct and the openings of the aerodynamic control device.
La figura 5 muestra una ampliación de la primera abertura del conducto tubular correspondiente a la figura 4. Descripción detallada de la invención Figure 5 shows an enlargement of the first opening of the tubular conduit corresponding to figure 4. Detailed description of the invention
El ejemplo de realización de las figuras adjuntas se corresponde con un perfil alar serie NACA 23012. Dicho perfil comprende una cara superior o extradós (20) y una cara inferior o intradós (21), un borde de ataque (22) y un borde de salida (23) localizado aguas abajo del borde de ataque (22). El dispositivo pasivo de control de flujo está localizado en el extradós (20). El dispositivo pasivo de control de dicho ejemplo de realización comprende: The exemplary embodiment of the attached figures corresponds to a NACA 23012 series wing profile. Said profile comprises an upper or upper face (20) and a lower or intrados face (21), a leading edge (22) and an edge of outlet (23) located downstream of the leading edge (22). The passive flow control device is located on the top surface (20). The passive control device of said exemplary embodiment comprises:
• una primera abertura (1) del cuerpo (24) localizada en la superficie del extradós• a first opening (1) of the body (24) located on the surface of the extrados
(20), (twenty),
• una segunda abertura (2) del cuerpo (24) localizada en la superficie del extradós (20) y aguas abajo de la primera abertura (1) en la dirección de avance del fluido, • a second opening (2) of the body (24) located on the surface of the extrados (20) and downstream of the first opening (1) in the direction of advance of the fluid,
• un conducto tubular (3) localizado dentro del cuerpo (24) del perfil aerodinámico y que se extiende entre la primera (1 ) y la segunda (2) aberturas. El conducto tubular (3) tiene su eje longitudinal en un plano paralelo a la dirección de avance del fluido. El conducto tubular (3) comprende una sección constante y al menos un tramo recto (3.1). El diámetro hidráulico está entre un 5% y un 30% de la distancia entre la primera abertura (1) y la segunda abertura (2) en la dirección de avance del fluido. • a tubular conduit (3) located inside the body (24) of the aerofoil and extending between the first (1) and the second (2) openings. The tubular conduit (3) has its longitudinal axis in a plane parallel to the direction of advance of the fluid. The tubular conduit (3) comprises a constant section and at least one straight section (3.1). The hydraulic diameter is between 5% and 30% of the distance between the first opening (1) and the second opening (2) in the direction of advance of the fluid.
Preferentemente, el diámetro hidráulico del conducto tubular (3) estará entre un 10% y un 20% de la distancia entre la primera abertura (1) y la segunda abertura (2) en la dirección de avance del fluido o de la cuerda para un óptimo funcionamiento del dispositivo. Más preferentemente, el diámetro hidráulico del conducto tubular (3) estará entre un 12% y un 17% de la distancia entre la primera abertura (1 ) y la segunda abertura (2). Como puede verse en las figuras 1 a 3, el perfil aerodinámico que comprende el dispositivo pasivo objeto de la invención retrasa el punto de transición en el que la capa límite pasa de un régimen laminar a turbulento a una velocidad aproximada de 250 km/h. Preferably, the hydraulic diameter of the tubular conduit (3) will be between 10% and 20% of the distance between the first opening (1) and the second opening (2) in the direction of advance of the fluid or of the rope for a optimal device performance. More preferably, the hydraulic diameter of the tubular conduit (3) will be between 12% and 17% of the distance between the first opening (1) and the second opening (2). As can be seen in Figures 1 to 3, the aerodynamic profile comprising the passive device object of the invention delays the transition point at which the boundary layer passes from a laminar to turbulent regime at a speed of approximately 250 km / h.
En el ejemplo de realización mostrado en las figuras, la cuerda del perfil es de aproximadamente 1 m y las condiciones de vuelo se modelizan sobre distintos ángulos de ataque frecuentes de las maniobras de despegue y aterrizaje de una aeronave. In the exemplary embodiment shown in the figures, the chord of the profile is approximately 1 m and the flight conditions are modeled on different angles of attack common to the takeoff and landing maneuvers of an aircraft.
Se tiene en cuenta una densidad dinámica del aire de 0.01682 mPas*s a condiciones de temperatura de 20 ºC y teniendo en cuenta la velocidad del aire de unos 250 km/h. Estas variables resultan en un número de Reynolds = 4900000, lo que significa que se sitúa en el régimen de transición de laminar a turbulento. A dynamic air density of 0.01682 mPas * s is taken into account at 20 ºC temperature conditions and taking into account the air speed of about 250 km / h. These variables result in a Reynolds number = 4900000, which means that it is in the transition regime from laminar to turbulent.
Más específicamente, en un ejemplo de realización, la primera abertura (1) está configurada de modo que la relación de fuerzas Cμ entre el flujo de aire que sale de la abertura (1 ) y el flujo de aire del fluido que se desliza sobre el extradós (20) en la proximidad de la abertura (1) está entre 0.10 y 0.25 según:
Figure imgf000011_0001
donde, es el coeficiente de momentos, es el flujo másico del fluido que sale del conducto tubular (3) a través de la abertura (1), More specifically, in an exemplary embodiment, the first opening (1) is configured so that the ratio of forces Cμ between the air flow leaving the opening (1) and the air flow of the fluid sliding over the upper surface (20) in the vicinity of the opening (1) is between 0.10 and 0.25 according to:
Figure imgf000011_0001
where, is the coefficient of moments, is the mass flow of the fluid that leaves the tubular conduit (3) through the opening (1),
V1 es la velocidad del fluido que sale del conducto tubular (3) a través de la abertura (1), siendo V1
Figure imgf000011_0002
es la densidad del fluido que se desliza sobre el extradós (20) es la velocidad del fluido que se desliza sobre el extradós (20) V 1 is the velocity of the fluid that leaves the tubular conduit (3) through the opening (1), where V 1
Figure imgf000011_0002
is the density of the fluid that slides on the upper surface (20) is the speed of the fluid that slides on the upper surface (20)
A es el área del conducto tubular (3) p1 es la densidad del fluido que sale del conducto tubular (3) a través de la aberturaA is the area of the tubular conduit (3) p 1 is the density of the fluid that leaves the tubular conduit (3) through the opening
(1) (1)
A1 es el área del conducto tubular (3) β1 el ángulo entre el eje longitudinal del conducto tubular (3) en la sección de la primera abertura (1 ) con el plano del extradós (20), el ángulo medido desde el plano del extradós (20) hacia el eje longitudinal del conducto tubular (3) en el sentido contrario a las agujas del reloj. A 1 is the area of the tubular duct (3) β 1 the angle between the longitudinal axis of the tubular duct (3) in the section of the first opening (1) with the plane of the extrados (20), the angle measured from the plane of the extrados (20) towards the longitudinal axis of the tubular duct (3) in the anticlockwise direction.
En un ejemplo de realización preferente, la relación de fuerzas Cμ entre el flujo de aire que sale de la abertura (1 ) y el flujo de aire del fluido que se desliza sobre el extradós (20) en la proximidad de la abertura (1 ) será de 0,17. In a preferred embodiment, the force ratio Cμ between the air flow leaving the opening (1) and the air flow of the fluid sliding on the extrados (20) in the vicinity of the opening (1) will be 0.17.
En las figuras 4 y 5 se representan esquemáticamente los detalles del conducto tubular (3) que comprende un tramo recto (3.2), un primer tramo curvo (3.1) que se extiende entre la primera abertura (1) y el tramo recto (3.2) y un segundo tramo curvo (3.3) que se extiende entre el tramo recto (3.2) y la segunda abertura (2). Figures 4 and 5 schematically represent the details of the tubular conduit (3) comprising a straight section (3.2), a first curved section (3.1) that extends between the first opening (1) and the straight section (3.2) and a second curved section (3.3) that extends between the straight section (3.2) and the second opening (2).
Más concretamente, en el ejemplo de realización mostrado, en el primer tramo curvo (3.1), en la sección de la primera abertura (1) el eje longitudinal forma un ángulo menor de 30º con el plano del extradós (20) medido desde el plano de la superficie (30) hacia el eje longitudinal en el sentido contrario a las agujas del reloj. More specifically, in the embodiment shown, in the first curved section (3.1), in the section of the first opening (1) the longitudinal axis forms an angle of less than 30º with the plane of the extrados (20) measured from the plane from the surface (30) towards the longitudinal axis in the counterclockwise direction.
De este modo, la primera abertura (1 ) o abertura de arrastre es, preferentemente, tangente o casi tangente al extradós (20) del perfil aerodinámico. Esto tiene la ventaja de que la dirección del flujo de aire arrastrado se mezcla en la misma dirección de avance de la capa límite. En caso de que lo hiciera con un ángulo mayor que 30º respecto al extradós (20) podría producirse una separación de la capa límite por la dirección del flujo arrastrado, aumentando, por lo tanto, el espesor de la capa límite. En el ejemplo de realización mostrado, dicho ángulo es, preferentemente, de 13º. In this way, the first opening (1) or trailing opening is preferably tangent or almost tangent to the extrados (20) of the aerodynamic profile. This has the advantage that the direction of the entrained air flow is mixed in the same direction of advance of the boundary layer. If it were done with an angle greater than 30º with respect to the extrados (20), a separation of the boundary layer could occur due to the direction of the entrained flow, thus increasing the thickness of the boundary layer. In the exemplary embodiment shown, said angle is preferably 13 °.
En un ejemplo de realización, el eje longitudinal del conducto tubular (3) en el segundo tramo curvo (3.3) en la sección de la segunda abertura (1) forma un ángulo entorno a 90º con el plano de la superficie (30). In an exemplary embodiment, the longitudinal axis of the tubular conduit (3) in the second curved section (3.3) in the section of the second opening (1) forms an angle of around 90 ° with the plane of the surface (30).
En el ejemplo de realización mostrado, el ángulo entre el eje longitudinal del conducto tubular (3) en la sección de la segunda abertura (2) y el eje longitudinal del conducto tubular (3) en el tramo recto (3.2) es superior a 90º. Como consecuencia, el eje longitudinal del tramo recto (3.2) no es paralelo a la superficie del extradós (20). Así se logra minimizar tramos de curvatura muy acentuada que pueden generar una pérdida instantánea en la inercia del fluido. In the exemplary embodiment shown, the angle between the longitudinal axis of the tubular conduit (3) in the section of the second opening (2) and the longitudinal axis of the tubular conduit (3) in the straight section (3.2) is greater than 90 ° . As a consequence, the longitudinal axis of the straight section (3.2) is not parallel to the surface of the extrados (20). Thus, it is possible to minimize stretches of very pronounced curvature that can generate an instantaneous loss in fluid inertia.
El conducto tubular (3) aprovecha la curvatura suave para generar una caída de la velocidad suave. Tramos ligeramente curvos en secciones cerradas, ayudan a la mezcla de los vectores de velocidad dentro del mismo y a que la corriente del flujo interior del conducto permanezca cercana al régimen laminar. Esto significa una ralentización paulatina de la velocidad interna del conducto, mejor para permanecer en régimen laminar dentro de conductos cerrados. Adicionalmente, el coeficiente de momentos de aire al mezclar corrientes en régimen laminar consigue un mejor resultado. The tubular conduit (3) takes advantage of the smooth curvature to generate a smooth speed drop. Slightly curved sections in closed sections, help the mixing of the velocity vectors within it and the flow current inside the conduit to remain close to the laminar regime. This means a gradual slowdown of the internal velocity of the duct, better to remain in a laminar regime within closed ducts. Additionally, the coefficient of air moments when mixing streams in a laminar regime achieves a better result.
Adicionalmente, la distancia entre la primera abertura (1) y la segunda abertura (2) está entre un 15% y un 25% de la longitud de la cuerda del perfil aerodinámico, preferentemente entre un 18% y un 20%. Additionally, the distance between the first opening (1) and the second opening (2) is between 15% and 25% of the chord length of the aerofoil, preferably between 18% and 20%.
En el ejemplo de realización mostrado en las figuras, el conducto tubular (3) y ambas aberturas (1 , 2) poseen la misma sección de 0.00045 m2 y existe una diferencia de presión entre ambas aberturas (1 , 2) de 6 mmHg, teniendo la primera abertura (1) una presión de 750,7 mmHg y la segunda abertura (2) una presión de 756,7 mmHg para un ángulo de ataque de 26º para un perfil alar serie NACA 23012 y una longitud de cuerda de ala de 1 m, siendo la temperatura 20 ºC, la densidad dinámica del aire de 0,01682 mPa*s y a la velocidad de 250 km/h con un número de Reynolds de 4900000, es decir, en el caso de estudio de régimen transicional laminar-turbulento. Con estas condiciones, la velocidad a la que el volumen de fluido contenido en el conducto tubular (3) sale de la primera abertura (1 ) es de 72 km/h mientras que el fluido circundante sobre la segunda abertura (2) posee una velocidad de 277 km/h. In the embodiment shown in the figures, the tubular conduit (3) and both openings (1, 2) have the same section of 0.00045 m 2 and there is a pressure difference between both openings (1, 2) of 6 mmHg, the first opening (1) having a pressure of 750.7 mmHg and the second opening (2) having a pressure of 756.7 mmHg for an angle of attack of 26º for a NACA 23012 series wing profile and a wing chord length of 1 m, the temperature being 20 ºC, the dynamic air density of 0.01682 mPa * s and the speed of 250 km / h with a Reynolds number of 4,900,000, that is, in the case of laminar-turbulent transitional regime study . Under these conditions, the speed at which the volume of fluid contained in the tubular conduit (3) leaves the first opening (1) is 72 km / h while the surrounding fluid over the second opening (2) has a speed of 277 km / h.
En un ejemplo de realización, el perfil aerodinámico comprende un conjunto de conductos tubulares (3) y primeras y segundas aberturas (1 , 2), estando dichos conductos tubulares (3) y sus correspondientes aberturas (1, 2) localizados alineados en la dirección de avance del fluido, de modo que las aberturas (1 , 2) quedan alineadas unas detrás de las otras en la dirección de avance del fluido. De este modo, van actuando en cascada sobre la capa límite, retrasando su separación de la superficie aerodinámica. En el caso de un perfil aerodinámico tipo alar las aberturas (1, 2) se localizarían en línea según la cuerda del mismo. In an embodiment, the aerodynamic profile comprises a set of tubular ducts (3) and first and second openings (1, 2), said tubular ducts (3) and their corresponding openings (1, 2) being located aligned in the direction advancement of the fluid, so that the openings (1, 2) are aligned one behind the other in the direction of advance of the fluid. In this way, they act in a cascade on the boundary layer, delaying its separation from the aerodynamic surface. In the case of a wing type aerodynamic profile, the openings (1, 2) would be located in line according to the chord of the same.
En otro ejemplo de realización, las aberturas (1, 2) podrían situarse de forma matricial sobre la superficie, es decir, no solamente en la dirección de avance del fluido, sino también en la dirección perpendicular al avance del fluido. En una aplicación conforme al ejemplo divulgado en las figuras y anteriormente citado y considerando una longitud en planta aproximada del dispositivo pasivo según la invención de 208 mm, es decir, una distancia entre aberturas (1 , 2) de 208 mm y un ancho de cada abertura (1 , 2) en planta de 50 mm, cada dispositivo pasivo ocuparía aproximadamente un área de 0.0104 m2. Considerando un área de un perfil alar de una aeronave de 59.7 m2y estimando que se utilizaría aproximada 1/5 de dicho área para la instalación de una matriz de dispositivos pasivos según la invención, la superficie ocupada por los mismos sería de 11.94 m2. Por lo tanto, el número de conductos (3) y aberturas (1 , 2) que podrían ser implementados en un ala de una aeronave de tipo de un único pasillo sería de 1148 unidades dispuestas, por ejemplo, matricialmente. Para la realización de un cálculo de la variación de la fuerza total de sustentación en un ala, se hace de nuevo uso del ejemplo de realización con las condiciones de contorno anteriormente expuestas, es decir, para un perfil alar serie NACA 23012, en situación de despegue para un ángulo de ataque de 26º, velocidad del flujo de aire libre de 250 km/h, densidad dinámica del aire de 0,01682 mPa*s, siendo la temperatura ambiente de 20 ºC, con un número de Reynolds de 4900000, es decir, en el caso de estudio de régimen transicional lamlnar-turbulento. Un perfil NACA23012 sin el dispositivo pasivo de sustentación objeto de la invención tiene una sustentación total de 518.8 Newton, mientras que el mismo perfil NACA23012con un dispositivo según el objeto de la invención tiene una sustentación total de 553.5 Newton, es decir, una variación de la fuerza de sustentación de 34.7 Newton. La equivalencia para unidades en kilogramos es de 3, 47 Kg de fuerza de sustentación que ejerce uno de los dispositivos pasivos de sustentación objeto de la invención. In another embodiment, the openings (1, 2) could be located in a matrix manner on the surface, that is, not only in the direction of advance of the fluid, but also in the direction perpendicular to the advance of the fluid. In an application according to the example disclosed in the figures and cited above and considering an approximate plan length of the passive device according to the invention of 208 mm, that is, a distance between openings (1, 2) of 208 mm and a width of each opening (1, 2) in plan of 50 mm, each passive device would occupy approximately an area of 0.0104 m 2 . Considering an area of a wing profile of an aircraft of 59.7 m 2 and estimating that approximately 1/5 of said area would be used for the installation of a matrix of passive devices according to the invention, the surface occupied by them would be 11.94 m 2 . Therefore, the number of ducts (3) and openings (1, 2) that could be implemented in a wing of a single-aisle type aircraft would be 1148 units arranged, for example, in a matrix. To perform a calculation of the variation of the total lift force in a wing, the exemplary embodiment is again used with the boundary conditions set forth above, that is, for a wing profile of the NACA 23012 series, in a situation of take-off for an angle of attack of 26º, free air flow speed of 250 km / h, dynamic air density of 0.01682 mPa * s, being the ambient temperature of 20 ºC, with a Reynolds number of 4900000, is that is, in the case of study of the laminar-turbulent transitional regime. A NACA23012 profile without the passive lifting device object of the invention has a total lift of 518.8 Newton, while the same NACA23012 profile with a device according to the object of the invention has a total lift of 553.5 Newton, that is, a variation of the lift force of 34.7 Newton. The equivalence for units in kilograms is 3.47 Kg of lift force exerted by one of the passive lift devices object of the invention.
Para el supuesto de una disposición matricial de un conjunto de conductos de 1148 unidades en una de las alas de la aeronave, supondría una variación de la fuerza total de sustentación de 3983.82 Kg, es decir, aproximadamente 4 toneladas en cada ala. Opcionalmente, la superficie del perfil aerodinámico localizada entre la primera abertura (1 ) y la segunda abertura (2) puede ser rugosa, lo que colabora en retrasar el punto de transición de laminar a turbulento de la capa límite. For the assumption of a matrix arrangement of a set of ducts of 1148 units in one of the wings of the aircraft, it would suppose a variation of the total lift force of 3983.82 Kg, that is, approximately 4 tons in each wing. Optionally, the surface of the aerodynamic profile located between the first opening (1) and the second opening (2) can be rough, which helps to delay the transition point from laminar to turbulent of the boundary layer.
Opcionalmente, también la superficie del conducto tubular (3) puede ser rugosa, con un acabado superficial de clase de rugosidad (Ra) de N7 a N12, según la norma UNE 1037. De este modo se favorece la existencia de un flujo laminar dentro del conducto tubular (3). Optionally, the surface of the tubular conduit (3) can also be rough, with a surface finish of roughness class (Ra) from N7 to N12, according to the UNE 1037 standard. In this way, the existence of a laminar flow within the tubular conduit (3).

Claims

REIVINDICACIONES
1 Perfil aerodinámico con dispositivo pasivo de control de flujo, el perfil aerodinámico comprendiendo al menos un cuerpo (24) y una superficie exterior de dicho cuerpo (24) configurada para el desplazamiento de un fluido sobre la misma (24), dicha superficie exterior comprendiendo un extradós (20) y un intradós (21), caracterizado por que el dispositivo pasivo de control de flujo comprende: 1 Aerodynamic profile with passive flow control device, the aerodynamic profile comprising at least one body (24) and an outer surface of said body (24) configured for the movement of a fluid thereon (24), said outer surface comprising an upper surface (20) and an upper surface (21), characterized in that the passive flow control device comprises:
• una primera abertura (1 ) en el cuerpo (24) localizada en la superficie del extradós• a first opening (1) in the body (24) located on the top surface
(20), (twenty),
• una segunda abertura (2) en el cuerpo (24) localizada en la superficie del extradós (20) y aguas abajo de la primera abertura (1), • a second opening (2) in the body (24) located on the surface of the extrados (20) and downstream of the first opening (1),
• un conducto tubular (3) localizado en el cuerpo (24) y que se extiende entre la primera (1) y la segunda aberturas (2), el conducto tubular (3) comprendiendo: al menos un tramo longitudinal recto (3.2), una sección constante a lo largo de su longitud, y un diámetro hidráulico entre un 5% y un 30% de la distancia entre la primera abertura (1) y la segunda abertura (2), estando la primera abertura (1), la segunda abertura (2) y el conducto tubular (3) configurados de modo que, en funcionamiento, la velocidad del fluido que se desplaza sobre el extradós (20) realiza un arrastre del fluido contenido en el interior del conducto tubular (3) a través de la primera abertura (1 ) y a su vez el arrastre del fluido del interior del conducto tubular (3) realiza una succión del fluido que se desplaza sobre el extradós (20) a través de la segunda abertura (2) hacia el conducto tubular (3). • a tubular conduit (3) located in the body (24) and extending between the first (1) and the second openings (2), the tubular conduit (3) comprising: at least one straight longitudinal section (3.2), a constant section along its length, and a hydraulic diameter between 5% and 30% of the distance between the first opening (1) and the second opening (2), the first opening (1) being the second opening (2) and the tubular conduit (3) configured so that, in operation, the speed of the fluid moving over the extrados (20) carries out a drag of the fluid contained inside the tubular conduit (3) through the first opening (1) and in turn the dragging of the fluid inside the tubular conduit (3) sucks the fluid that moves on the extrados (20) through the second opening (2) towards the tubular conduit (3 ).
2.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según la reivindicación 1 , caracterizado por que el diámetro hidráulico del conducto tubular (3) está entre un 12% y un 17% de la distancia entre la primera abertura (1) y la segunda abertura (2). 2.- Aerodynamic profile with passive flow control device, according to claim 1, characterized in that the hydraulic diameter of the tubular conduit (3) is between 12% and 17% of the distance between the first opening (1) and the second opening (2).
3.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizada por que el eje longitudinal del conducto tubular (3) está localizado en un plano sustancialmente paralelo a la dirección de la cuerda del perfil aerodinámico. 4.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizado por que la primera abertura (1) está configurada de modo que, en funcionamiento, la relación de fuerzas Cμ entre el flujo de aire que sale de la abertura (1) y el flujo de aire del fluido que se desliza sobre el extradós (20) en la proximidad de la abertura (1) está entre 0.10 y 0.25 según:
Figure imgf000017_0001
donde es el coeficiente de momentos
Figure imgf000017_0002
es el flujo másico del fluido que sale del conducto tubular (3) a través de la abertura (1) 3. Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that the longitudinal axis of the tubular duct (3) is located in a plane substantially parallel to the direction of the chord of the aerodynamic profile. 4.- Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that the first opening (1) is configured so that, in operation, the force ratio Cμ between the air flow that comes out of the opening (1) and the air flow of the fluid that slides on the extrados (20) in the vicinity of the opening (1) is between 0.10 and 0.25 according to:
Figure imgf000017_0001
where is the coefficient of moments
Figure imgf000017_0002
is the mass flow of the fluid that leaves the tubular conduit (3) through the opening (1)
V1 es la velocidad del fluido que sale del conducto tubular (3) a través de la abertura (1), siendo V1
Figure imgf000017_0003
es la densidad del fluido que se desliza sobre el extradós (20) es la velocidad del fluido que se desliza sobre el extradós (20) V 1 is the velocity of the fluid that leaves the tubular conduit (3) through the opening (1), where V 1
Figure imgf000017_0003
is the density of the fluid that slides on the upper surface (20) is the speed of the fluid that slides on the upper surface (20)
A es el área del conducto tubular (3) p1 es la densidad del fluido que sale del conducto tubular (3) a través de la aberturaA is the area of the tubular conduit (3) p 1 is the density of the fluid that leaves the tubular conduit (3) through the opening
(1) (1)
A1 es el área del conducto tubular (3) β1 el ángulo entre el eje longitudinal del conducto tubular (3) en la sección de la primera abertura (1 ) con el plano del extradós (20), el ángulo medido desde el plano del extradós (20) hacia el eje longitudinal del conducto tubular (3) en el sentido contrario a las agujas del reloj A 1 is the area of the tubular duct (3) β 1 the angle between the longitudinal axis of the tubular duct (3) in the section of the first opening (1) with the plane of the extrados (20), the angle measured from the plane of the upper surface (20) towards the longitudinal axis of the tubular duct (3) in an anti-clockwise direction
5.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizado por que el conducto tubular (3) comprende un tramo recto (3.2), un primer tramo curvo (3.1) que se extiende entre la primera abertura (1 ) y el tramo recto (3.2) y un segundo tramo curvo (3.3) que se extiende entre el tramo recto (3.2) y la segunda abertura (2). 5.- Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that the tubular duct (3) comprises a straight section (3.2), a first curved section (3.1) that extends between the first opening (1) and the straight section (3.2) and a second curved section (3.3) that extends between the straight section (3.2) and the second opening (2).
6.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según la reivindicación 5, caracterizado por que el eje longitudinal del conducto tubular (3) en el primer tramo curvo (3.1) en la sección de la primera abertura (1) forma un ángulo menor de 30º con el plano del extradós (20), el ángulo medido desde el plano del extradós (20) hacia el eje longitudinal del conducto tubular (3) en el sentido contrario a las agujas del reloj. 6.- Aerodynamic profile with passive flow control device, according to claim 5, characterized in that the longitudinal axis of the tubular conduit (3) in the first curved section (3.1) in the section of the first opening (1) forms a angle less than 30º with the plane of the extrados (20), the angle measured from the plane of the extrados (20) towards the longitudinal axis of the tubular duct (3) in the anticlockwise direction.
7.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según la reivindicación 6, caracterizado por que el ángulo entre el eje longitudinal del conducto tubular (3) en el primer tramo curvo (3.1) en la sección de la primera abertura (1 ) y plano del extradós (20) es igual a 13º. 7. Aerodynamic profile with passive flow control device, according to claim 6, characterized in that the angle between the longitudinal axis of the tubular conduit (3) in the first curved section (3.1) in the section of the first opening (1 ) and the plane of the extrados (20) is equal to 13º.
8.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones 5 a 7, caracterizado por que el eje longitudinal del conducto tubular (3) en el segundo tramo curvo (3.3) en la sección de la segunda abertura (2) forma un ángulo de aproximadamente 90º con el plano del extradós (20). 8.- Aerodynamic profile with passive flow control device, according to any one of claims 5 to 7, characterized in that the longitudinal axis of the tubular conduit (3) in the second curved section (3.3) in the section of the second opening (2) forms an angle of approximately 90º with the plane of the upper surface (20).
9.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según la reivindicación 8, caracterizado por que el ángulo entre el eje longitudinal del conducto tubular (3) en la sección de la segunda abertura (2) y el eje longitudinal del conducto tubular (3) en el tramo recto (3.2) es superior a 90º. 9.- Aerodynamic profile with passive flow control device, according to claim 8, characterized in that the angle between the longitudinal axis of the tubular conduit (3) in the section of the second opening (2) and the longitudinal axis of the tubular conduit (3) in the straight section (3.2) it is greater than 90º.
10.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizado por que la distancia entre la primera abertura (1) y la segunda abertura (2) está entre un 15% y un 25% de la longitud de la cuerda del perfil aerodinámico. 11.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizado por que comprende un conjunto de conductos tubulares (3) y primeras y segundas aberturas (1 , 2), estando dichos conductos tubulares (3) y sus correspondientes primeras y segundas aberturas (1 , 2) localizados alineados entre sí en la dirección de avance del fluido. 12.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según la reivindicación10.- Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that the distance between the first opening (1) and the second opening (2) is between 15% and 25% of the chord length of the airfoil. 11.- Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that it comprises a set of tubular conduits (3) and first and second openings (1, 2), said tubular conduits (3) being ) and their corresponding first and second openings (1, 2) located aligned with each other in the direction of advance of the fluid. 12.- Aerodynamic profile with passive flow control device, according to claim
11 , caracterizado por que comprende adicionalmente un conjunto de conductos tubulares (3) y primeras y segundas aberturas (1 , 2), estando dichos conductos tubulares (3) y sus correspondientes primeras y segundas aberturas (1 , 2) localizados alineados en la dirección perpendicular a la de avance del fluido. 13.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizado por que la superficie del extradós (20) localizada entre la primera abertura (1) y la segunda abertura (2) en la dirección de avance del fluido es rugosa, con un acabado superficial de clase de rugosidad (Ra) de N7a N12. 11, characterized in that it additionally comprises a set of tubular conduits (3) and first and second openings (1, 2), said tubular conduits (3) and their corresponding first and second openings (1, 2) being located aligned in the direction perpendicular to the fluid advance. 13.- Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that the surface of the extrados (20) located between the first opening (1) and the second opening (2) in the direction of fluid advance is rough, with a surface finish of roughness class (Ra) of N7 to N12.
14.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizado por que la superficie del conducto tubular (3) es rugosa, con un acabado superficial de clase de rugosidad (Ra) de N7a N12. 14. Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that the surface of the tubular conduit (3) is rough, with a surface finish of roughness class (Ra) of N7 to N12.
15.- Perfil aerodinámico con dispositivo pasivo de control de flujo, según una cualquiera de las reivindicaciones anteriores, caracterizado por que el dispositivo de control de flujo está localizado en una superficie sustentadora de una aeronave o en un alerón o en un flap o en un slat de dicha superficie sustentadora. 15.- Aerodynamic profile with passive flow control device, according to any one of the preceding claims, characterized in that the flow control device is located on an airfoil of an aircraft or on an aileron or on a flap or on a slat of said bearing surface.
PCT/ES2020/070615 2019-10-09 2020-10-09 Aerofoil with passive flow-control device WO2021069789A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ESP201930886 2019-10-09
ES201930886A ES2818751A1 (en) 2019-10-09 2019-10-09 Aerodynamic profile with passive flow control device (Machine-translation by Google Translate, not legally binding)

Publications (1)

Publication Number Publication Date
WO2021069789A1 true WO2021069789A1 (en) 2021-04-15

Family

ID=75420227

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/ES2020/070615 WO2021069789A1 (en) 2019-10-09 2020-10-09 Aerofoil with passive flow-control device

Country Status (2)

Country Link
ES (1) ES2818751A1 (en)
WO (1) WO2021069789A1 (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE501548C (en) * 1927-08-31 1930-07-04 Alexander Lippisch Device for preventing the flow from breaking off on areas subject to flow
DE584585C (en) * 1929-07-28 1933-09-21 Kaeser Ernst Device for increasing the transverse drive of bodies moving relative to the surrounding medium, such as aircraft wings and the like. like
DE586496C (en) * 1929-08-06 1933-10-21 Kaeser Ernst Device for increasing the transverse drive of bodies moving relative to the surrounding medium such as aircraft wings and the like. like
US2219234A (en) * 1937-09-24 1940-10-22 Messerschmitt Willy Arrangement for sucking-off the boundary layer on airplane wings
US2427972A (en) * 1944-02-01 1947-09-23 Frederick C Melchior Self-energizing airfoil
US2441694A (en) * 1945-05-19 1948-05-18 Earl V Ehrhardt Adjustable airfoil and boundary layer control
RU2015941C1 (en) * 1991-10-14 1994-07-15 Научно-производственное предприятие "Триумф" Method to control boundary layer on aerodynamic surface of aircraft
US20030150962A1 (en) * 2002-02-12 2003-08-14 Bela Orban Method for controlling and delaying the separation of flow from a solid surface by suction coupling (controlling separation by suction coupling, CSSC)
US20180065732A1 (en) * 2016-09-05 2018-03-08 Airbus Defence and Space GmbH Fluidic actuator having jet vector control and flow body

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE501548C (en) * 1927-08-31 1930-07-04 Alexander Lippisch Device for preventing the flow from breaking off on areas subject to flow
DE584585C (en) * 1929-07-28 1933-09-21 Kaeser Ernst Device for increasing the transverse drive of bodies moving relative to the surrounding medium, such as aircraft wings and the like. like
DE586496C (en) * 1929-08-06 1933-10-21 Kaeser Ernst Device for increasing the transverse drive of bodies moving relative to the surrounding medium such as aircraft wings and the like. like
US2219234A (en) * 1937-09-24 1940-10-22 Messerschmitt Willy Arrangement for sucking-off the boundary layer on airplane wings
US2427972A (en) * 1944-02-01 1947-09-23 Frederick C Melchior Self-energizing airfoil
US2441694A (en) * 1945-05-19 1948-05-18 Earl V Ehrhardt Adjustable airfoil and boundary layer control
RU2015941C1 (en) * 1991-10-14 1994-07-15 Научно-производственное предприятие "Триумф" Method to control boundary layer on aerodynamic surface of aircraft
US20030150962A1 (en) * 2002-02-12 2003-08-14 Bela Orban Method for controlling and delaying the separation of flow from a solid surface by suction coupling (controlling separation by suction coupling, CSSC)
US20180065732A1 (en) * 2016-09-05 2018-03-08 Airbus Defence and Space GmbH Fluidic actuator having jet vector control and flow body

Also Published As

Publication number Publication date
ES2818751A1 (en) 2021-04-13

Similar Documents

Publication Publication Date Title
ES2564078T3 (en) Supersonic airplane
US11485472B2 (en) Fluid systems that include a co-flow jet
US8752788B2 (en) Wing and a multiple propeller aircraft
US10246197B2 (en) Aircraft
US10625847B2 (en) Split winglet
US9586677B2 (en) Aircraft wing with system establishing a laminar boundary layer flow
US3525486A (en) Vortex generators
ES2256481T3 (en) AIRCRAFT CONFIGURATION WITH IMPROVED AERODYNAMIC PERFORMANCES.
IL257811B (en) Fluidic propulsive system
CN107021207B (en) Aircraft flow device for passive boundary layer suction
US20160280358A1 (en) Hybrid Flow Control Method for Simple Hinged Flap High-Lift System
US8910910B2 (en) Wing comprising a flow fence, and aircraft having such wings
US20020014555A1 (en) Method for altitude control and/or pitch angle control of airships, and an airship having a device for altitude control and/or pitch angle trimming
CN110271658B (en) Leading edge structure for an airflow control system of an aircraft
CN107848619B (en) Fluid flow control of an airfoil
EP2987721A1 (en) Nose cone structure for pylon of aircraft with wing-hung layout
US9701399B1 (en) Parasitic drag induced boundary layer reduction system and method
US20130153711A1 (en) Minimally intrusive wingtip vortex wake mitigation using inside-mold-line surface modifications
US20130146715A1 (en) Minimally intrusive wingtip vortex wake mitigation using microvane arrays
WO2021069789A1 (en) Aerofoil with passive flow-control device
EP2987728A1 (en) Airplane suspension cowling structure with wing-mounted arrangement
US4860976A (en) Attached jet spanwise blowing lift augmentation system
US4457480A (en) Mono-element combined supercritical high lift airfoil
KR20100072668A (en) A natural laminar flow airfoil for very light jets
EP3077282A1 (en) Aerodynamic device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20875128

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20875128

Country of ref document: EP

Kind code of ref document: A1