DE202016000269U1 - Wing with integrated engine gondolas - Google Patents

Abstract

Wing, with on each side of the aircraft at least one inflow opening 8 along its leading edge and at least one outflow opening 28 along its trailing edge characterized in that in the interior of the wing of the inflow opening 8 and the outflow opening 28 associated blower units 10 are arranged side by side.

Description

Technical area

The invention relates to an aircraft wing with integrated engines according to the preamble of claim 1.

State of the art

On an aircraft there is an airfoil for generating lift and engines for generating propulsion attached thereto, generally in multi-engine airplanes.

The engines are the prior art turbofan engines with a fan and a core engine, which are mounted in engine gondolas on pylons on the wing. The engine nacelles cause a relatively constant flow velocity to the fan inside the nacelle, regardless of the airspeed. This allows a rigid connection of the blades to the fan hub and a higher airspeed in contrast to free propellers.

In order to support the wheel brakes for deceleration of the aircraft during landing after touchdown flap systems are installed on the engine nacelles, which serve the deflection of the engine blower jet against the direction of flight or rolling in order to generate braking thrust.

The wing generally includes a front and rear flap system which serves to increase lift during takeoff and landing. In a first detent, lift enhancement is primarily caused by enlargement of the airfoil surface and in the minor by warping, which is achieved by pivoting and extending the front flap system forward and downwards, and extending the rear flap system rearward and slightly downward pivoting.

In other notches, the rear flap system is adjusted by further axial extension in combination with a pivoting and rotating movement of the flap segments. Both measures cause a further increase in the area and the curvature of the wing, which is associated with a further lift increase. In order to avoid flow separation in the region of the rear flap system, connecting gaps between the flap elements are opened by the axial method, which allow an overflow of air from the bottom to the top of the flap elements. Due to the high pressure difference prevailing there and the consequent high flow velocity of the overflowing air, the flow is stabilized on the upper sides of the flap elements and thus prevented from detaching.

However, the increase of the curvature and the overflow of air through the connecting gaps also lead to a large increase in the flow resistance of the wing, so that these higher detent positions are used only on landing and not for takeoff. Also, to assist the wheel brakes on landing after touchdown, the airbrakes are swung vertically upwards. The brakes cause not only a braking backlog of air in front of the flap, but also open a very large connection channel from the bottom to the top of the wing, which causes the collapse of the entire lift. This increases the contact pressure of the landing gear on the runway, whereby the effectiveness of the wheel brakes is increased.

To consume as little fuel to produce the necessary propulsion the fans of the turbofan engines must be sized as large as possible in the design of the aircraft to capture the largest possible air mass flow, which is accelerated in the direction of flight to the rear.

The enlargement of the wind instruments inevitably entails an increase in the diameter of the engine nacelles, which must include the winds. This results in an increased wetted by the flow surface of the nacelle, which has an increased frictional resistance result and thus partially compensates for the fuel savings from the increase in diameter.

The effect of a nearly constant flow velocity to the fan in an engine nacelle is due in large part to the critical pressure ratio which it builds up to blow out the compressed air at the speed of sound from the exhaust nozzle at the rear end of the engine nacelle. As a result, the flow inside the nacelle is almost decoupled from the ambient conditions, which has the advantages already described. However, if the diameter of the fan is increased, its pressure ratio must be lowered to keep the thrust constant. So that we no longer emanate at the speed of sound at the speed of the exhaust nozzle, whereby the decoupling from inside to outside is lost. This leads to Fehlanströmungen the fan. To compensate for this, either a blade adjustment on the fan or a variable exhaust nozzle must be provided. Both measures lead to a further increase in the engine mass or the nacelle mass, which in turn leads to an increase in fuel consumption.

Next results in an installation problem of the nacelle on the wing. Since the aircraft nacelles must never touch the ground on aircraft, even in the case of a failed landing with extreme inclination, they must not project beyond an imaginary line between the landing gear and the wing tips. If the nacelle diameter is increased, the chassis must be increased for the same span of the wing to meet this condition. An elevated chassis is, if it can be installed without additional bulges on the hull, at least heavier than a shorter and thus also contributes to an increase in fuel consumption.

Another problem of further enlarged engine gondolas is the behavior of the aircraft in the event of failure of a nacelle drive to call. In this case, the flow resistance of the failed gondola increases drastically and approximately in proportion to their cross-sectional area.

For the engine failure at the start of larger gondolas so an ever greater excess thrust on the remaining engines must be held in order to guarantee even a low gradeability. The engines thus deviate further and further from optimal tuning for normal flight, which in turn results in more fuel consumption.

In addition, the yaw moment increases disproportionately, since the increase of the nacelle diameter together with the chassis problem also the distance of the engine nacelle to the center of the hull must be increased. For compensation, the fin has to be increased, which results in a further increase in weight and thus increases the fuel consumption.

Both effects have a particularly strong impact on aircraft with only two engines.

It is thus obvious that, with the concept of installed engine nacelles, the fuel consumption can only be reduced to a certain limit, since the advantage of an increased mass air flow detected is increasingly counteracting fuel-consuming disadvantages.

Presentation of the invention

Object of this invention is a further fuel savings by increasing the air mass flow to thrust generation, while preserving all the features of a current wing with engine gondolas while avoiding the disadvantages indicated.

For this purpose, the engine nacelles are no longer attached to the wing via pylons, but integrated into them. The resulting engine nacelle-wing combination is hereinafter referred to as nacelle wings.

For this, a plurality of small diameter fan units are arranged side by side along the airfoil extension in the interior of the nacelle in the area of the largest profile thickness. At the front of the nacelle wing there is an inflow opening along its extension, through which air can flow into the nacelle wing and reach the blower units. At the rear of the nacelle wing there is a corresponding outflow opening from which the air coming from the blower units flows out of the nacelle wing again.

The cross-sectional area of the trapezoidal inflow port is approximately equal to the sum of the circular cross-sectional areas of the associated fan motors of the fan units. The cross-sectional area of the discharge opening is slightly smaller and acts as a nozzle.

In order to prevent a backflow of the air between the circular fan rotor surfaces and the substantially trapezoidal cross-sections of the gondola interior, baffles are incorporated in the remaining free gussets to close them.

The front fins are shaped so that they evenly transform the trapezoidal front flow channel in the circular shapes of the fan motors and thereby accelerate the flow. The rear baffles are reversely shaped and return the circular flow channel to the rectangular shape, thereby retarding the flow. The front and rear vanes together with a blower motor form a blower unit.

The wetted by the flow surface of this configuration while maintaining the axial length is equal to or less than that of a freely installed engine nacelle, provided that the ratio of height to width of the inlet opening is equal to or greater than about 1/8. This can be explained by the fact that with the integration of the engine nacelle into the wing, the outer surface of the nacelle as well as that of the pylon is omitted.

Thus, an increase in the frictional resistance is avoided by the in principle unfavorable trapezoidal flow cross-section.

As already explained is an increase in the fan air mass flow and lowering the fan pressure ratio to reduce fuel consumption either a blade adjustment on the fan rotor or a variable exhaust nozzle necessary. If, for reasons of cost and weight, blower motors with rigid rotor blades are to be used in the nacelle, which are operated with a low pressure ratio and high mass flows, a variable exhaust nozzle is necessary. Due to the linear arrangement of the fan motors along the extension of the wing, this is particularly easy to set up by a nozzle flap passing through several fan units at the end of the lower part of the nacelle wing. In order to be able to tune all blower units with a nozzle flap, this is set back so far that the individual blow jets of the blower units before this are again combined to form a single common blow jet.

To maintain buoyancy on the nacelle, the nozzle flow must always flow parallel to the flow on the top of the nacelle wing. To ensure this at different opening cross sections of the nozzle flap, this ends slightly before the end of the trailing edge of the upper part of the nacelle wing. The upper part projecting backwards must be dimensioned so that it has a sufficient directing effect on the jet.

Optionally, the inlet opening can also be made variable by a diffuser flap at the front of the lower part of the nacelle wing according to the same principle as the nozzle flap. This allows a further improved adaptation of the flow in the nacelle, whereby losses can be reduced and thus fuel can be saved.

The known in aircraft of the prior art front and rear flap system is taken on the nacelle wings and changed only slightly. A change affects the known Krügerklappen if they are used for the front flap system. Such flaps can not be applied to the nacelle due to the inlet opening. But it is possible to swing flaps or slats from the top to the bottom front and thus to obtain the same function.

The rear flap system is unchanged from the structure, however, must be built more stable, since it is integrated with extended flaps in the deflection of the thrust jet down to further increase the buoyancy, which is not the case with separately suspended engine nacelles. This is a further advantage for the fuel savings, since the wing increase can be reduced by increasing the lift and this causes a reduction of the flow resistance in the cross-country flight.

The thrust reverser to assist the wheel brakes on landing is possible in the nacelle wing as in a free nacelle as a cascade or flap thrust reverser. The nacelle wings are the outflow openings of the deflected air jet on the bottom. The blow-out is designed in such a way that individual interrupted blast jets form to the front in order to avoid pressure build-up under the nacelle wing and thus avoid the emergence of buoyancy.

In the interior of the nacelle shutter flaps are pivoted into the flow channel of the individual fans, which block the connection to the nozzle and release the area of the outflow in the lower part of the nacelle. Depending on the design of a flow reversal by a cascade outside of the nacelle wing down a thrust reverser cover is moved backwards or swung at a deflection by flaps such.

The upper part of the nacelle wing is constructed as a torsion box to give it the necessary rigidity against twisting. The lower part of the nacelle wing mechanically serves mainly to transmit tensile forces transmitted by outcrossings. The concept of the nacelle wing is so by the larger profile thickness, compared to known wings, significantly stiffer and thus lighter, resulting in another advantage in terms of fuel economy.

It is also obvious that in comparison to an installed engine nacelle considerable height is saved, which avoids the problem of adjusting the landing gear for the inclined landing.

The fan motors of the juxtaposed blower units are individually preferably driven by high-performance electric motors, which draw their electric power via a multi-redundant hybrid system of gas turbine-powered generators and high-performance batteries or only on such batteries.

The electric motors are installed in motor nacelles, which are preferably attached to the outcrossings between the upper and lower part of the nacelle wing. The motor gondolas are aerodynamically shaped. The struts of the outcrossings are designed like a wing in the area of the flow channel of the blower unit and, in addition to their mechanical function, additionally constitute a guide grid for the swirling flow from the blower motors. Between the outcrossings can be arranged even more flow profiles to improve the Leitgitterfunktion. Through the guide grid, the swirl of the flow is converted to the fan motors in pressure and / or axial flow velocity and therefore serves to increase the efficiency of the blower unit.

The large number of fan motors with separate drives increases the probability of failure of a fan unit in the overall drive system. This is a common problem of multi-engine aircraft, which is solved by the design of the overall drive system for the failure of one or more components.

For the nacelle in the form described so far, this error would be particularly critical, since the merging of the jets of individual blower units in front of the common nozzle of the failure of a single blower unit would also influence the still functioning units. To solve the problem to the shutter flaps of the thrust reverser are not continuous, but designed separately closable for each individual fan unit. Further, the rear vanes of each blower unit terminate to form a closed space with no connection to the common exhaust nozzle, together with a pair of closed flaps.

If now a blower unit fails, this can be removed by closing the associated flap pair from the composite of the remaining units. This avoids backflow within the nacelle from back to front through the failed blower unit and limits the impact of the failure on the still functioning blower units.

The unfavorably changed by the failure flow through the nacelle is then adjusted by adjusting the nozzle surface on the nozzle flap and the inlet flap so that again set the best possible flow conditions on the remaining fan units.

This procedure can be continued over multiple failures until complete failure of all fan units. Even for this extreme case, it must be ensured that the nacelle wing provides enough lift, at least for a steep glide flight to an emergency landing area. Thus, by extending the rear and front flap systems together with the closing of the nozzle and inlet flaps, a profile geometry and airfoil surface can be produced which ensures these note characteristics.

Due to the possibility of adapting the blade geometry in the event of a fan unit failure, in contrast to an installed nacelle, there is hardly any additional gondola resistance which would have to be compensated for with additionally installed engine power. This also applies to the therefore also not occurring additional yaw moment, which avoids an adaptation of the vertical stabilizer.

Therefore, and taking into account the high number of redundant blower units, only a very small overshoot must be kept available for a fault in the nacelle, which makes it possible to design the system very close to the optimum for the normal flight case, which saves fuel.

For the flight in the speed range just below the speed of sound, a sweep of the wing to reduce the resistance is favorable. This sweep can also be realized in the nacelle wing, for which purpose the fan units are arranged in a staircase along the then sloping support foot extension. The inlet and nozzle flaps continue unchanged parallel to the front and the rear edge of the nacelle wing, which in turn can not run parallel but as usual from the wing root acute angle direction wing ends.

In addition to the generally noise-reducing effect of increased air mass flow for thrust generation, the noise-generating fan motors inside the nacelle wing, because of the relatively long flow channels, very well shielded from the environment. With the incorporation of noise abatement surface elements in this area and the use of noise-encapsulated engines for the generators and especially in the pure battery operation of the aircraft is expected to extremely low noise emissions at the level of gliders. A 24-hour flight operation, even in noise-sensitive regions, therefore seems possible.

Brief description of the invention

The invention will now be described by way of example without limitation of the general inventive idea using an exemplary embodiment with reference to the drawings. Show it:

1 a plan view of an aircraft with two engine gondolas according to the prior art

2 a plan view of an aircraft with double entry surface of the gondolas, left with two and right with an engine nacelle, in a configuration according to the prior art

3 a plan view of an aircraft with nacelle wings in landing configuration with a doubled entrance surface in the prior art as in 2

4 a top view of the plane with gondola wing 3 in flight configuration

5 a plan view of the mechanical structure of the nacelle wing 3

6 a 3D view of the blower units with outbreaks of the nacelle wing 3

7 a longitudinal section of the outer profile of the nacelle wing in cruise configuration with representation of the skeleton line

8th a longitudinal section through the gondola wing 7 ;

9 a longitudinal section through the gondola wing 7 in startup configuration;

10 a longitudinal section through the gondola wing 7 in landing configuration;

11 a longitudinal section through the gondola wing 7 in thrust reversal configuration;

12 a longitudinal section through the gondola wing 7 in case of failure of a blower unit;

13 a longitudinal section through the gondola wing 7 in case of failure of several blower units in gliding configuration;

Ways to carry out the invention, industrial usability

1 shows a prior art aircraft with two engine nacelles 1 a landing gear 2 in landing configuration and 2a in flight configuration. The L lines from the wing tips 3 to the suspension set the dependence of the diameter of the engine nacelles 1 and their position relative to the wing height and span, at which the engine nacelle may not extend beyond it.

In 2 are the conditions for the case of a doubling of the entrance surface 4 of the engine gondolas 1 shown. On the left side we achieved this by installing a second identical engine nacelle. Line L1 shows that even with the extreme position of the landing gear marked here, the condition for an "oblique" landing can hardly be maintained. In addition, it can be seen that the landing gear must be positioned at least very close to the inner nacelle to even find the possibility of a constructive solution for retracting the landing gear for the flight.

On the right side is the doubling of the entrance area 4 achieved by the corresponding enlargement of the nacelle diameter. With the line L2 for the chassis condition, it can be seen that the problematic conditions for positioning have not changed or improved. The illustration thus shows that the doubling of the nacelle entry surfaces selected here by way of example with an aircraft configuration according to the prior art is scarcely or not at all feasible.

3 shows the plane 2 with gondola wing 5 with two fan groups each 6 and 7 per page. The inflow opening 8th the blower group 6 is designed in the ratio height to width 1/8 and includes five fan units 10 , The inflow openings 9 the blower group 7 is formed in the ratio height to width 1/5 and includes three fan units 10 ,

The blower groups are completed on both sides 6 & 7 through lever boxes 11 in which the mechanisms for the different flap systems are housed. In the middle lever box 11m is additionally the chassis 12 what additional accommodated in the flight position 12a is shown. Right on the fuselage 13 There are air inlets 14 for the engines for power generation, not shown here.

The lines 13 show the trouble-free installation of the chassis 12 in the gondola wing with respect to the condition "oblique landing" also with extended flaps 15 ,

4 shows the plane with gondola wing 5 in flight configuration. The fan groups 6 & 7 extend over the span so that in the area of the wing tips 3 still enough space for the ailerons 16 is present, which are not shown here directly.

In 5 is the mechanical structure of the nacelle wing 5 out 3 shown. The outcrossings 17 connect the upper belt here 18 with the bottom strap 19 of the gondola wing 5 , The motor gondolas 20 for the blower motors 21 are attached to these. In the gussets 22 between the circular flow channels 23 the blower motors 21 and the trapezoidal surface between upper chord 18 and bottom strap 19 are the outcrossings 17 with this mechanically connected. Around circular flow channels 23 are the outcrossings 17 designed as a flow profile.

In 6 are fan units 10 without upper strap 18 and bottom strap 19 but with outcrossings 17 , front fins 24 , the circular flow channel 23 with blower motor 21 and the rear fins 25 of the gondola wing 5 out 3 shown in a 3D view.

7 shows a longitudinal section of the outer profile 26 of the gondola wing 5 in cruise configuration with the associated skeleton line 27 , This is curved down to increase lift. Shown is the inflow opening 8th , which is slightly tilted down to the normal flight case as perpendicular to the inflow 29 to stand, as well as the outflow opening 28 which acts as a nozzle. The supernatant U on the outer profile 26 is dimensioned so large that the blow jet 30 is directed parallel to the supernatant U.

8th shows the inner structure of the nacelle wing 7 , At the upper belt 18 is above the inflow opening 8th a slat 33 appropriate. Above the discharge opening 28 is a known from the prior art landing flap system consisting of a brake flap 37 a front landing flap 38 and a rear landing flap 39 ,

At the bottom strap 19 is below the inlet opening 8th a diffuser flap 32 appropriate. Below the discharge opening 28 there is a nozzle flap 31 , Inside the gondola wing 5 is the fan motor 21 with the engine nacelle 20 about the outcrossing 17 fixed. Along with the front and rear baffles 24 & 25 and the circular flow channel 23 These form a blower unit 10 ,

In the area of the rear fins 25 There are two flaps 35 and below a cascade deflector 34 inside through one of the flaps 35 and externally by a thrust reverser cover 36 is covered.

9 shows the nacelle wing in start configuration with extended slat 33 , down open diffuser door 32 , flaps extended to the rear 38 & 39 and downwardly opened nozzle flap 31 ,

The flap position of the flaps on the upper flange 18 serves the largest possible wing area with suitable warping for the start.

The flap positions of the inlet flap 32 and the nozzle flap 31 at the bottom strap 19 are used to optimally tune the blower unit on the during the start-up run and the climb constantly changing environmental conditions and is therefore only exemplary.

According to the changing parameters, these are continuously changed in order to always operate the complete system optimally.

10 shows the nacelle wing in landing configuration with extended slat 33 and completely extended and downwardly flapped landing flaps 38 & 39 , The positions of the diffuser flap 32 and the nozzle flap 31 are again drawn by way of example, since these according to the thrust and buoyancy requirements in dependence on the power output of the fan units 10 be set. Visible is like the blow jet 30 is deflected downward and thus contributes to the buoyancy of the nacelle wing. In addition, part of the air mass flow of the blower unit 10 branched off and as Blasstrahl 30a on the top of the front landing flap 38 directed where it stabilizes the flow and prevents it from detaching. This serves an additional increase in buoyancy.

11 shows the nacelle wing in thrust reverser configuration shortly after landing on landing. These are all the flaps 35 closed and at the same time the thrust reverser cover 36 open. The blow jet 30b will now be on the cascade deflector 34 steered diagonally forward down and brakes the plane.

Also at the same time as known in the art, the brake flap 37 pivoted upward, whereby a braking accumulation of the flow builds up in front of this and at the same time the buoyancy of the landing flaps 38 & 39 collapses.

12 shows the nacelle wing in case of failure of a blower unit in an adapted configuration. The flaps 35 are at the failed blower unit shown here 10 closed, on the other non-failed fan units (which are not shown here) they are open. This is a back flow of air from back to front through the failed fan unit 10 prevents recirculation of air within the fan group 6 and thus would lead to a strong loss of thrust.

Because of the one failed and closed blower unit 10 less air gets to the nozzle 28 guided, which is why their cross-sectional area by upward pivoting of the nozzle flap 31 is reduced. This will allow for still functioning blower units 10 again set the same pressure ratio as before the failure and kept this in the optimum operating range.

Like us, the cross-sectional area of the inflow opening 8th by pivoting the diffuser door 32 adjusted upwards to the reduced air flow to an air accumulation in front of the nacelle wing 5 to avoid. This could increase the flow resistance and lower the buoyancy which is thereby avoidable.

13 shows the nacelle wing in case of failure of several or all fan units in gliding configuration. These are the flaps 38 & 39 as well as the slat 33 extended into a starting configuration similar position, the flaps 35 each failed fan units 10 closed and the diffuser door 32 as well as the nozzle flap 31 to the appropriate air mass flow through the remaining blower units 10 customized. The gliding configuration ensures that even if all fan units fail 10 all fan groups 6 & 7 on the aircraft still enough lift is guaranteed for a gliding flight to an emergency landing area.

LIST OF REFERENCE NUMBERS

1

Engine nacelle

2

Landing gear in landing configuration

2a

Landing gear in flight configuration

L

Line "sloping landing"

L1

Line "sloping landing"

L2

Line "sloping landing"

L3

Line "sloping landing"

3

Hydrofoil tip

4

entry surface

5

gondola wings

6

blower

7

blower

8th

inflow

9

inflow

10

blower unit

11

lever box

11m

middle lever box

12

landing gear

12a

Landing gear in flight position

13

fuselage

14

air inlet

15

flaps

16

aileron

17

outcrossing

18

upper chord

19

lower chord

20

nacelle

21

fan rotor

22

gore

23

circular flow channel

24

front fins

25

rear fins

26

outer profile

27

skeleton line

28

Orifice / nozzle

29

inflow

30

blowing jet

30a

blowing jet

30b

blowing jet

U

Got over

31

nozzle flap

32

diffuser flap

33

vane

34

Cascade deflector

35

flap

36

Thrust reverser cover

37

airbrake

38

front landing flap

39

rear flap

Claims (15)

Hydrofoil, with at least one inflow opening on each side of the aircraft 8th along its leading edge and at least one discharge opening 28 along its trailing edge characterized in that in the interior of the wing of the inflow opening 8th and the discharge opening 28 associated fan units 10 are located side by side. A wing according to claim 1, characterized in that the cross-sectional area of the outflow opening 28 via a nozzle flap 31 is variably adjustable. Wing according to claim 1, characterized in that the underside of the outflow opening 28 is a distance U axially spaced from the top. Wing according to claim 1, characterized in that the fan units 10 axially to the discharge opening 28 are spaced. A wing according to claim 1, characterized in that the cross-sectional area of the inflow opening 8th via a diffuser flap 32 is variably adjustable. Wing according to claim 1, characterized in that the fan units 10 axially to the inlet opening 8th are spaced. Wing according to claim 1, characterized in that the fan units 10 individually at its rear end over a pair of flaps 35 are closable. A wing according to claim 7, characterized in that each blower unit 10 a cascade deflector 34 owns which of a flap 35 is covered and which at the bottom of the wing over a thrust reverser cover 36 is covered. A wing according to claim 7, characterized in that each blower unit 10 has a deflecting flap, which by a flap 35 is covered and which can swing out the bottom of the wing. Wing according to one of claims 1 to 9, characterized in that the upper flange 18 is constructed as a torsion box and over outcrossings 17 with the bottom strap 19 connected is. Wing according to one of claims 1 to 10, characterized in that the upper flange 18 a landing flap system is attached. A wing according to any one of claims 1 to 11, characterized in that each blower unit 10 an electrically operated fan motor 21 owns that via a motor nacelle 20 and an outcrossing 17 is attached in the wing. A wing according to any one of claims 10 to 12, characterized in that the outcrossing 17 in the area of the fan motor 21 aerodynamically designed as a guide grid. Wing according to claim 13, characterized in that in the region of the outcrossing 17 additional flow profiles are mounted as a guide grille. A wing according to any one of claims 1 to 14, characterized in that the electric power is provided for the operation of the fan units via gas turbines operated generators and or batteries.

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