DE102009007325A1 - Negative device on the front edge of wing surfaces of a missile with a hull/fuselage or a hull-like body includes a free-flow/wind direction parallel to a hull/fuselage with the converse to the flight direction of a missile/aircraft - Google Patents

Abstract

A free-flow direction or wind direction (8) parallel to a hull/fuselage (3) has the converse to the flight direction of a missile/aircraft. The presence of a wing surface of finite thickness causes an oncoming flow to have a component (10) in the direction of a front edge or tailback/congestion line (4). This component transports a contaminated boundary layer along the front edge or tailback/congestion line as far as a negative device (1) and then transports a new laminar boundary layer (12) as far as a wing's end.

Description

Introduction, State of the art

The Boundary layer and its structure and distribution over the surface of a missile have a significant importance in civil and military Aircraft, flight control body and rocket construction. Also the construction of wind turbines and other turbomachinery is affected.

At missiles with a fuselage and several swept wings (wings or tail) becomes the Boundary layer flow on the wings of the boundary layer flow influenced on the hull. The boundary layer flow reaches the hull in the Usually up to the wing root a highly turbulent character, therefore one speaks of a "contamination" of the flow through the wing the hull.

All Aircraft and rocket manufacturers are striving to find a solution for avoidance or elimination the contamination of the wing boundary layer through the turbulent hull boundary layer to find. Such solutions can be "active" or "passive". The active solutions use additional Energy sources, eg. For example the extraction of the contaminated boundary layer or branches of the energy available to the missile. Some passive solutions try the boundary layer flow via transition control by means of small vortex generation by artificial roughness for certain Laminate pressure gradient.

Known is the use of boundary layer fences on the wings (z. Fiat G91 or Suchoi SU22), the "Gaster bump" by M. Gaster (1965) as well as deflecting and separating devices according to Krier (2006, 2007, 2008). The solution by Gaster represents a kind of bump "bump" that is more than "dam" for the contaminated Boundary layer acts. In contrast, the solution presents according to patent No. 10 2006 054 428 a low-loss deflection device (flow-optimized Solution). This consists of a streamlined shaped body, the on the leading edge of the wing can be mounted and thus in particular for the "decontamination" existing missile suitable is. This solution and the Gaster solution be considered "positive" devices seen because of the device body into the flow in front of the wing protrudes. This requires the realization of a smooth transition from the plateau of the device (origin of the new laminar boundary layer) over the Trailing edges to the wing leading edge behind the device, which is a technological challenge. For missiles that are still in the design phase and therefore still have all the options and possibilities open, one can use the separation device (Krier 2008) as a possible solution use the wing root. But if a solution at the wing root for one missile not possible in the design phase is, would be a "negative" solution - one from the Front edge machined device - an advantage.

Of the Invention is based on the object, a negative passive device to design, which is capable of the contaminated boundary layer split at the front edge and on the top and bottom the wing Redirect loss.

The solution This object is achieved with the characterizing features of claim 1 Fulfills.

description

The Leading edge of the wing or the wing is for the generation and for the transport of the boundary layer flow prevailing, as in the normal Fall the contaminated boundary layer of the fuselage along this leading edge moves. Will the turbulent (contaminated) boundary layer along the leading edge of the wing Diverted, then arises at the leading edge of a new laminar Boundary layer caused by locomotion in the spanwise direction the entire boundary layer over the wing controls.

The solution according to claim 1 consists in a negative device on the front edge of Wing. These can be easily imagined by taking a block out the leading edge of the wing disconnects, from it according to the drawing Milled out material or -brennt and reinksetzt in the same place.

The turbulent boundary layer along the leading edge is replaced by a specially shaped feed surface low loss directed towards the interior of the wing, through a dividing edge shared and over the top and bottom of the device forwarded in the flow direction. The starting point for a new, uncontaminated boundary layer is created on the leading edge, immediately after the dividing edge. The division and the forwarding have to be done so that upstream and downstream of the device one possible minor disturbance occurs. Numerical investigations of the solution according to claim 1 show that the presence of this device virtually no increase in the Resistance has.

• – aus einem speziell geformten Körper in einem Ausschnitt der Vorderkante eingesetzt,
• – oder aus der speziell geformten Vorderkante, der/die mittels verschiedener Kanten und Flächen zwei Funktionen gleichzeitig erfüllt:
• – die verlustarme Zuleitung, Teilung, Lenkung und Weiterleitung der entlang der Vorderkante kommenden, turbulenten Grenzschicht über die Ober- und Unterseite der Vorrichtung,
• – die Erzeugung einer neuen, nicht kontaminierten Grenzschicht auf der Vorderkante unmittelbar nach der Vorrichtung, die verlustfrei entlang der Vorderkante in Spannweitenrichtung weitergeleitet wird.

The device consists of either:

• - Inserted from a specially shaped body in a section of the front edge,
• - or from the specially shaped front edge, the / by means of various edges and surfaces fulfilled two functions simultaneously:
• The low-loss supply line, division, steering and forwarding of the turbulent boundary layer along the leading edge via the top and bottom of the device,
• - The generation of a new, uncontaminated boundary layer on the leading edge immediately after the device, which is forwarded lossless along the leading edge in the spanwise direction.

• a) die Funktionsweise ist passiv, d. h. sie arbeitet ohne Energiezufuhr
• b) sie ist praktisch für alle Arten von Tragflächen (Flügel, Leitwerke) eines Flugkörpers in Unter-, Trans- oder Überschallströmung, die vom Rumpf kontaminiert werden, anwendbar
• c) sie führt zu geringerem spezifischen Kraftstoffverbrauch, geringerer Lärmentwicklung und geringerer Schadstoffemission.

In addition, this device has the following properties:

• a) the operation is passive, ie it works without energy
• b) it is practically applicable to all types of wings (tail, tail) of a missile in sub, trans or supersonic flow, which are contaminated by the fuselage
• c) it leads to lower specific fuel consumption, less noise and lower pollutant emissions.

• 1
• 2
• 3
• 4
• 5

In the following the invention will be described in more detail with reference to an embodiment. Show it

• 1
• 2
• 3
• 4
• 5

The embodiments are for a wind tunnel model provided.

According to the list of reference numerals at the end of this description, the most important parts of the device are shown in FIG 1 shown.

• A) Sie hat eine speziell geformte Zuleitfläche (7), die eine S-Form (2 und 3) oder eine halbe S-Form (4 und 5), je nach Form der Leitlinie, haben kann. Diese geht in zwei Übergansflächen zur Tragfläche über.
• B) Sie hat eine Teilungskante (5) mit einer spitz zulaufenden oder abgerundeten Nase, die ungefähr senkrecht zur Vorderkante (4) liegt, um verlustarm die gesamte ankommende turbulente Grenzschicht zu teilen.
• C) Sie hat zwei Umlenk- und Führungsflächen (6), die in Stromlinienrichtung zu der Ober- und auf der Unterseite der Tragfläche verlaufen und die geteilte turbulente Grenzschicht (11) in Windrichtung über die Tragfläche leiten.

The outline sketch in 1 shows in plan view and in perspective the fuselage with the swept wing. The free-flow direction or wind direction ( 8th ) has the reverse of the direction of flight of the missile. Therefore, in the sketch the arrows of the free flow direction are parallel to the fuselage ( 3 ). The presence of the wing of finite thickness causes the flow to be a component ( 10 ) in the direction of the leading edge or jam line ( 4 ) having. This component transports the contaminated boundary layer along the leading edge or jam line to the device ( 1 ) and then the new laminar boundary layer ( 12 ) to the end of the wing. Within the device, this is done along a single or double curved guideline, which up to the dividing edge ( 5 ) of the device. The shape (the course) of this guideline is crucial for the development of the contaminated boundary layer up to the dividing edge. The negative device is mounted in a designated section of the leading edge of the wing and has some important characteristics for trouble-free division:

• A) It has a specially shaped feed surface ( 7 ), which have an S-shape ( 2 and 3 ) or half an S-shape ( 4 and 5 ), depending on the form of the guideline. This transitions to the wing in two transition areas.
• B) It has a dividing edge ( 5 ) with a pointed or rounded nose, which is approximately perpendicular to the leading edge ( 4 ) to share the entire incoming turbulent boundary layer with little loss.
• C) It has two deflecting and guiding surfaces ( 6 ), which run in the direction of the streamline to the top and on the underside of the wing and the divided turbulent boundary layer ( 11 ) in the wind direction over the wing.

An embodiment of the solution is as a drawing in 2 , a second in 3 presented. These correspond to a wind tunnel model. Decisive is the geometry of the device, which ensures by the design of Vorleitfläche, the dividing edge and the deflection downstream, that the contaminated boundary layer is gently divided (low loss) and forwarded. If one cuts the device through a plane parallel to the plane of symmetry of the missile, one gets the upper picture in 1 . 2 and 4 , where some important parameters of the cross section are drawn. The most important parameters of the device are the shape of the lead surface ( 7 ), the position and direction of the dividing edge ( 5 ) with respect to leading edge ( 4 ), the nose radius of the dividing edge and the height of the device (or length of the dividing edge).

The dividing edge - with no. 5 in 1 marked - is the area of the device that first comes in contact with the turbulent boundary layer and, as the name implies, divides it into two halves. To optimally fulfill this task, this dividing edge must be as perpendicular as possible to the leading edge. Theoretically, the deflection flanks ( 6 ) form an acute angle (φ) (significantly smaller than 90 °) at the dividing edge. Values up to 10 ° -20 ° were successfully tested. Practically, this edge will have a small fillet radius that depends on the task for the device. The task may provide a precise angle of attack for the design or a range thereof. On the one hand, the larger the fillet radius, the larger the coverage angle covered. Strength and erosion aspects also play an important role for this edge. On the other hand, the larger the nose radius (fillet radius) of the dividing edge, the greater the congestion effect in front of it. This could lead to transmission of the contaminated boundary layer to the leading edge - and thus failure of the main function of the device - if the altitude (or Län ge) the dividing edge is insufficient. Therefore, it is recommended to provide the height of this edge in the order of the diameter of the nose.

materials:

The negative device may be made of similar materials like the leading edge of the wing (Aluminum, steel, titanium alloys or composites) become.

Assembly:

The negative device should as possible close to the hull, but outside its boundary layer, in a designated section in the leading edge of the wing be firmly mounted in order to achieve maximum benefits. It allowed no noticeable transition (no step) between the wing and the device arise.

1

negative deflecting

2

wing

3

hull

 4

leading edge the wing or stagnant line

5

dividing edge the device

6

side flanks (Umleitflanken)

7

Zuleitflächen or Vorleitflächen

8th

inflow direction

9

turbulent Fuselage boundary layer

10

contaminated Boundary layer along the front edge

11

redirected contaminated boundary layer

12

formation a new laminar boundary layer

Claims (3)

A negative device at the leading edge of swept wings of a missile having a torso or body similar to a body, characterized in that it is machined directly from the front edge of the wing or, 2. that it consists of a single, specially shaped body in which the following is worked out is: 3. a gentle supply line along a single or double curved guideline, 4. which continues in two lateral channels with approximately triangular cross section, 5. which extend in the direction of the undisturbed flow on the top and bottom of the wing 6. and perpendicular to the wing surface extending side edges form a tapered or rounded dividing edge, which - is perpendicular to the front edge and - points with the tip in the direction of the fuselage. Device according to claim 1, characterized in that that they especially in airplanes, rockets, flying bodies, drones and space ferries Use finds. Device according to one of the preceding claims, characterized characterized in that the dividing edge or the side edges of a other angles than 90 ° with form the wing surface.