CN108674674A - Suitable for supersonic speed unmanned plane without control formula strategy oil consumption fuel tank and unmanned plane - Google Patents

Abstract

The disclosure provide it is a kind of suitable for supersonic speed unmanned plane without control formula strategy oil consumption fuel tank and unmanned plane, should include without control formula strategy oil consumption fuel tank suitable for supersonic speed unmanned plane：It is set gradually to tail direction along the prow of unmanned plane：Head fuel tank, middle part fuel tank and tail portion fuel tank；Head fuel tank, middle part fuel tank and tail portion fuel tank are sequentially connected in series, and pressure inlet is provided on the fuel tank of head, are provided with fuel feed pump on the fuel tank of tail portion, and when unmanned plane during flying, fuel feed pump fuel feeding, and by boost port to head fuel-tank pressurization realizes that fuel tank group is connected oil consumption.What the disclosure provided is suitable for the series connection oil consumption strategy that fuel tank group is utilized without control formula strategy oil consumption fuel tank and unmanned plane of supersonic speed unmanned plane, and optimize the volume of each seed oil case according to mission profile, to suitably reduce the superelevation steady state stability of supersonic flight, reach and reduce trim resistance, improves the purpose of unmanned plane during flying performance.

Description

Non-controlled strategic fuel-guzzling fuel tanks and UAVs suitable for supersonic UAVs

technical field

The present disclosure relates to the technical field of aviation vehicles, in particular to an uncontrolled strategic fuel-consuming fuel tank suitable for supersonic unmanned aerial vehicles and an unmanned aerial vehicle.

Background technique

When a supersonic UAV flies at a supersonic speed, the shock resistance of the UAV is the main component of the overall resistance, and at this time the overall resistance is much greater than that of subsonic flight, so reducing the shock resistance is the key to supersonic speed. One of the goals of UAV aerodynamic shape design. One of the effective ways to reduce shock wave resistance is to reduce the maximum cross-sectional area of the equivalent rotational body of the whole machine. Therefore, the body of a supersonic UAV presents a large slenderness ratio, generally above 12. Since most supersonic UAVs use axial-flow engines, such as turbojet or turbofan engines, the position of the fuel tank in the body will be before the center of gravity of the whole machine, so the UAV will go from being fully fueled to In the state of empty fuel, the center of gravity will move backward. A supersonic UAV will experience a subsonic-supersonic-subsonic process in the entire mission profile, and the focus of the subsonic and supersonic UAVs will vary greatly, generally reaching more than 30% MAC. The backward shift of the center of gravity from the state of full fuel to empty fuel is beneficial to the trimming of supersonic flight, but for a statically stable UAV, the rear limit of the center of gravity of empty fuel is still in front of the subsonic focus, so when flying at supersonic speed, the full The static stability of the aircraft is still greater than 30%, and the increase of trim resistance is not conducive to the performance of supersonic flight performance.

Due to the large fuel demand for supersonic flight, the fuel tank of a supersonic UAV accounts for a large proportion of the internal volume of the fuselage, so the fuel tank also presents a large slenderness ratio. In order to reduce the impact of the attitude angle of the fuselage on the center of gravity of the whole machine during the fuel consumption process, the fuel tank will be cut into several small fuel tanks. The traditional fuel tank will adopt the method of uniform fuel consumption, that is, the fuel of each sub-tank will be consumed at the same time; another One solution is to use the fuel tank near the center of gravity as the consumed fuel tank, and use the fuel management system to control the fuel consumption sequence, which can properly reduce the trim resistance during flight.

However, in the process of realizing the present disclosure, the inventors of the present application found that the uniform fuel consumption method will linearly move the center of gravity of the whole machine to the empty fuel center of gravity during the fuel consumption process, so this solution has a relatively high static stability at supersonic speeds , which is not conducive to the performance of supersonic flight performance; the method of using the fuel management system to control the fuel consumption process has a large number of hardware and sensors in the fuel management system, the control strategy is relatively complicated, the manufacturing cost is high, and the weight is large, so the above two methods cannot meet the requirements. Requirements for the use of drones.

public content

(1) Technical problems to be solved

Based on the above technical problems, this disclosure provides an uncontrolled strategic fuel consumption fuel tank and UAV suitable for supersonic UAVs, so as to alleviate the static stability of the uniform fuel consumption method in the prior art at supersonic speed. It is not conducive to the performance of supersonic flight; the method of fuel management system to control the fuel consumption process, the control strategy is relatively complicated, the manufacturing cost is high, and the technical problems are heavy.

(2) Technical solution

According to one aspect of the present disclosure, there is provided a non-controlled strategic fuel-consuming fuel tank suitable for supersonic UAVs, including: sequentially arranged along the direction from the nose to the tail of the UAV:

The head oil tank is provided with a booster pipe;

a middle tank communicating with said head tank; and

The tail fuel tank communicates with the middle fuel tank, the tail fuel tank is provided with an oil supply pipe, and the volume of the tail fuel tank satisfies the following formula:

Wherein, the V _tail is the volume of the tail fuel tank, W ₂ is the total weight of the UAV when flying at supersonic speed, and W ₁ is the total weight of the UAV under the state of empty fuel; Oil, and pressurize the head fuel tank through the pressure boost port to realize the oil consumption of the fuel tank group in series.

In some embodiments of the present disclosure, the middle fuel tank includes N pieces, and the N middle fuel tanks are arranged in series, and the head and the tail are respectively connected with the head fuel tank and the tail fuel tank, wherein N≥1.

In some embodiments of the present disclosure, the aft fuel tank is provided with a fuel filler, including: a gravity fuel filler, disposed on the top of the aft fuel tank; and a pressure fuel filler, disposed at the bottom of the aft fuel tank.

In some embodiments of the present disclosure, the pressure filling port is arranged on a branch of the oil supply pipe, and a check valve is arranged on the branch.

In some embodiments of the present disclosure, it also includes: an oil return pipe, arranged on a branch of the oil supply pipe, for transporting the fuel in the oil supply pipe back to the head fuel tank; wherein, the oil return pipe is provided with The pressure relief valve is opened when the pressure in the oil supply pipe reaches a set value.

In some embodiments of the present disclosure, an oil pump is provided on the fuel supply pipe for pumping out the fuel in the rear fuel tank.

In some embodiments of the present disclosure, an oil level sensor is arranged in the tail oil tank for monitoring the oil level in the tail oil tank.

In some embodiments of the present disclosure, the fuel level sensor is used to monitor the fuel level in the rear fuel tank after the fuel in the head fuel tank and the middle fuel tank is depleted.

In some embodiments of the present disclosure, the bottoms of the head oil tank, the middle oil tank and the tail oil tank are all provided with oil drains.

According to another aspect of the present disclosure, a supersonic unmanned aerial vehicle is also provided, and the uncontrolled strategic fuel consumption fuel tank suitable for the supersonic unmanned aerial vehicle provided by the present disclosure is arranged in the body of the unmanned aerial vehicle.

(3) Beneficial effects

From the above technical solutions, it can be seen that the uncontrolled strategic fuel-consuming fuel tank and the unmanned aerial vehicle suitable for supersonic unmanned aerial vehicle provided by the present disclosure have one or part of the following beneficial effects:

(1) Utilize the series fuel consumption strategy of the fuel tank group, and optimize the volume of each sub-fuel tank according to the mission profile, so as to appropriately reduce the ultra-high static stability of supersonic flight, reduce the trim resistance, and improve the flight performance of the UAV ;

(2) The serial fuel consumption strategy provided by the disclosure effectively takes into account the advantages of the traditional uniform fuel consumption tank and the fuel control system tank, that is, it has the advantages of simple system composition, high reliability, low manufacturing cost and light weight;

(3) By setting the oil return pipe and the pressure relief valve, when the oil pressure of the oil supply pipe is greater than the specified value, the pressure relief valve is opened, and the fuel returns to the head fuel tank through the oil return pipe, so as to achieve the purpose of controlling the pressure of the oil supply pipe;

(4) By setting the fuel quantity sensor, it is convenient for the pilot to control the flight time, plan the flight mission, and ensure enough fuel to return home.

Description of drawings

FIG. 1 is a schematic structural diagram of an uncontrolled strategic fuel-consuming fuel tank suitable for a supersonic UAV provided by an embodiment of the present disclosure.

FIG. 2 is a schematic perspective view of a sectional view of a drone provided by an embodiment of the present disclosure.

[Description of main component symbols of the embodiment of the present disclosure in the accompanying drawings]

10- head fuel tank;

11 - booster pipe;

20 - middle fuel tank;

30 - tail fuel tank;

31-oil supply pipe;

32 - Gravity refueling port;

33-Pressure filling port;

34 - one-way valve;

35 - oil pump;

36-Oil level sensor

40-oil return pipe;

41 - pressure relief valve;

50-oil drain port.

Detailed ways

The uncontrolled fuel consumption strategy suitable for supersonic UAVs provided by the embodiments of the present disclosure and the serial fuel consumption strategy of UAVs using fuel tank groups optimize the volume of each sub-tank according to the mission profile, thereby appropriately reducing the supersonic speed. The ultra-high static stability of the flight achieves the purpose of reducing the trim resistance and improving the flight performance of the UAV.

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

FIG. 1 is a schematic structural diagram of an uncontrolled strategic fuel-consuming fuel tank suitable for a supersonic UAV provided by an embodiment of the present disclosure.

According to one aspect of the present disclosure, there is provided an uncontrolled strategic fuel-consuming fuel tank suitable for supersonic UAVs. As shown in FIG. 10, which is provided with a booster pipe 11; the middle fuel tank 20 communicates with the head fuel tank 10; The volume satisfies the following formula:

Wherein, V _tail is the volume of the tail fuel tank 30, W ₂ is the total weight of the UAV when flying at supersonic speed, W ₁ is the total weight of the UAV under the state of empty fuel, and when the UAV is flying, the oil supply pipe 31 supplies fuel, and pressurize the head fuel tank 10 through the booster pipe 11, so that the fuel is emptied along the head fuel tank 10, the middle fuel tank 20 and the tail fuel tank 30 in sequence, realizing the fuel consumption strategy of fuel tank groups connected in series.

After design optimization, the center of gravity when flying at supersonic speed satisfies the following formula:

in,

W ₀ is the full fuel gross weight of the supersonic UAV (unit: kg), CG ₀ is the longitudinal center of gravity position in the full fuel state (unit: m, the reference origin is the leading edge point of the nose, and the backward direction is the positive axis direction ), W ₁ is the total weight of empty fuel (unit: kg), CG ₁ is the longitudinal center of gravity position (unit: m) in the empty fuel state, AC ₀ is the focus position during subsonic flight (unit: m), and AC ₁ is Focus position during supersonic flight (unit: m), W ₂ is the total weight of the UAV during supersonic flight (unit: kg), MAC is the average aerodynamic chord length of the UAV (unit: m), LD is the weight of the fuel tank Slenderness ratio (length/maximum cross-sectional area equivalent circle diameter), assuming that the air-fuel state is in the static stability limit state of subsonic flight, that is, the static stability margin is zero, AC ₀ =CG ₁ .

At the same time, the volume of each sub-fuel tank is optimized according to the mission profile, so as to appropriately reduce the ultra-high static stability of supersonic flight, achieve the purpose of reducing trim resistance and improving the flight performance of the UAV; on this basis, the serial fuel consumption strategy effectively takes into account It has the advantages of traditional uniform fuel consumption tank and fuel control system tank, that is, it has the advantages of simple system composition, high reliability, low manufacturing cost and light weight.

The division of the head fuel tank 10 and the middle fuel tank 20 can be divided according to the mission profile before the supersonic flight, but the static stability of the supersonic flight will not be affected.

In some embodiments of the present disclosure, the middle fuel tank 20 includes N, and the N middle fuel tanks 20 are arranged in series, and the head and tail are connected to the head fuel tank 10 and the tail fuel tank 30 respectively, where N≥1. According to the situation, design a reasonable total fuel capacity and design a reasonable number of fuel tanks.

In some embodiments of the present disclosure, as shown in FIG. 1 , the rear fuel tank is provided with a fuel filler, including: a gravity fuel filler 32 arranged on the top of the tail fuel tank 30 ; and a pressure fuel filler 33 arranged at the bottom of the tail fuel tank 30 , during actual application, fuel oil can be added in the fuel tank group by gravity filler 32 or pressure filler 33, the order of refueling is tail fuel tank 30, middle part fuel tank 20, head fuel tank 10, need seal gravity filler 32 after refueling.

In some embodiments of the present disclosure, as shown in FIG. 1 , the pressure filling port 33 is set on the branch of the oil supply pipe 31, and a check valve 34 is set on the branch. During the process of refueling the fuel port 33 into the rear fuel tank 30, the fuel will not leak from the pressure refueling port, which makes the refueling process more convenient.

In some embodiments of the present disclosure, as shown in FIG. 1 , it also includes: a fuel return pipe 40, which is arranged on the branch of the fuel supply pipe 31, and is used to transport the fuel in the fuel supply pipe 31 back to the head fuel tank 10; wherein , the oil return pipe 40 is provided with a pressure relief valve 41, which opens when the pressure in the oil supply pipe 31 reaches the set value, and when the oil pressure in the oil supply pipe 31 is greater than the specified value, the pressure relief valve 41 opens, and the fuel passes through the oil return pipe 40 returns to the head oil tank 10 to achieve the purpose of controlling the pressure of the oil supply pipe 31, thereby avoiding excessive pressure in the oil supply pipe 31, causing situations such as rupture of the oil supply pipe 31.

In some embodiments of the present disclosure, as shown in FIG. 1 , an oil pump 35 is provided on the fuel supply pipe 31 for pumping out the fuel in the rear fuel tank 30 to improve fuel supply efficiency.

In some embodiments of the present disclosure, as shown in FIG. 1 , a fuel level sensor 36 is arranged in the tail fuel tank 30 for monitoring the fuel level in the tail fuel tank 36 . By setting the fuel quantity sensor 36 , it is convenient for the pilot to control the flight time. , plan the flight mission, and ensure enough fuel to return home.

In some embodiments of the present disclosure, the fuel level sensor 36 is used to monitor the fuel level in the aft fuel tank 30 after the fuel in the head fuel tank 10 and the middle fuel tank 20 is depleted.

In some embodiments of the present disclosure, as shown in FIG. 1 , the bottoms of the head fuel tank 10 , the middle fuel tank 20 and the tail fuel tank 30 are all provided with an oil discharge port 50 , so as to facilitate the discharge of the unmanned aerial vehicle after returning from the mission. Empty the fuel in the fuel tank group and clean the inside of the fuel tank group.

FIG. 2 is a schematic perspective view of a sectional view of a drone provided by an embodiment of the present disclosure.

According to another aspect of the present disclosure, there is also provided a supersonic UAV, as shown in Figure 2, the UAV body is provided with an uncontrolled strategy suitable for supersonic UAVs provided by the embodiments of the present disclosure Fuel-guzzling tank.

In the following, a specific embodiment is used to verify the beneficial effects of the non-controlling strategic fuel-consuming fuel tank and the drone suitable for supersonic drones provided by the embodiments of the present disclosure.

Assume that the total weight of a small supersonic UAV equipped with an afterburner turbojet engine is full of fuel W ₀ =250kg, the longitudinal center of gravity CG ₀ of the full fuel state is 2.69m, the total weight of the empty fuel is W ₁ =182kg, and the empty fuel is 182kg. The longitudinal center of gravity CG ₁ in the state is 2.78m, the focal longitudinal position AC ₀ =2.78m during subsonic flight, and the focal longitudinal position AC ₁ =2.99m during supersonic flight; the total weight of the UAV during supersonic flight is W ₂ = 206kg, the average aerodynamic chord length MAC=0.68m, the slenderness ratio of the fuel tank LD=5, the density of aviation kerosene is 800kg/m3, the total volume of the UAV fuel tank is V ₀ =0.085m ³ , assuming that the fuel tank is divided into three parts Fuel tanks (that is, the number of fuel tanks in the middle is 1).

When adopting the embodiment of the present disclosure to provide an uncontrolled strategic fuel consumption tank suitable for supersonic drones, according to the formula The volume of the tail fuel tank 30 is set as V _tail =30L, then when flying at supersonic speed, the center of gravity CG ₂ of the whole machine=2.794m, the static stability margin

For a fuel tank with traditional uniform fuel consumption, when the total weight of the drone is W ₂ , the center of gravity is CG ₂ =2.753m, and the static stability margin

It can be seen from the comparison that the static stability of the non-controlled strategic fuel-consuming fuel tank suitable for supersonic UAVs provided by the embodiments of the present disclosure can reduce the static stability of the larger static stability by about 6% during supersonic flight. The position of the center of gravity of the two schemes is the same in the state of full fuel and empty fuel.

Based on the above description, those skilled in the art should have a clear understanding of the uncontrolled strategic fuel-consuming fuel tank and the drone suitable for supersonic drones provided by the present disclosure.

In summary, this disclosure provides an uncontrolled strategy for supersonic UAVs and a series fuel consumption strategy for UAVs using fuel tank groups, and optimizes the volume of each sub-tank according to the mission profile, so as to properly Reduce the ultra-high static stability of supersonic flight, achieve the purpose of reducing trim resistance and improving the flight performance of UAVs.

It should also be noted that the directional terms mentioned in the embodiments, such as "up", "down", "front", "back", "left", "right", etc., are only referring to the directions of the drawings, not Used to limit the protection scope of this disclosure. Throughout the drawings, the same elements are indicated by the same or similar reference numerals. Conventional structures or constructions are omitted when they may obscure the understanding of the present disclosure.

And the shape and size of each component in the figure do not reflect the actual size and proportion, but only illustrate the content of the embodiment of the present disclosure. Furthermore, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Similarly, it should be appreciated that in the above description of exemplary embodiments of the disclosure, in order to streamline the disclosure and to facilitate an understanding of one or more of the various disclosed aspects, various features of the disclosure are sometimes grouped together into a single embodiment, figure, or its description. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the foregoing claims reflect, disclosed aspects lie in less than all features of a single foregoing disclosed embodiment. Thus the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this disclosure.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present disclosure in detail. It should be understood that the above descriptions are only specific embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included within the protection scope of the present disclosure.

Claims (10)

1. An uncontrolled strategic fuel tank suitable for supersonic unmanned aerial vehicles, comprising: set gradually along unmanned aerial vehicle's aircraft nose to tail direction:

the head oil tank is provided with a pressure increasing pipe;

the middle oil tank is communicated with the head oil tank; and

the afterbody oil tank, with middle part oil tank intercommunication is provided with on this afterbody oil tank and supplies oil pipe, just the volume of afterbody oil tank satisfies the following formula:

wherein ,V_TailIs the volume of the tail tank, W₂Is the total weight of the unmanned aerial vehicle in supersonic flight, W₁The total weight of the unmanned aerial vehicle in an empty state;

when unmanned aerial vehicle flies, supply oil pipe fuel feeding to through the pressure boost mouth to the pressurization of head oil tank, realize the oil tank group and establish ties the oil consumption.

2. The uncontrolled strategic fuel tank for supersonic unmanned aerial vehicles of claim 1, wherein the number of the middle fuel tanks comprises N, the N middle fuel tanks are arranged in series and are respectively communicated with the head fuel tank and the tail fuel tank from head to tail, wherein N is more than or equal to 1.

3. The uncontrolled strategic fuel tank for supersonic drones of claim 1, the tail tank being provided with a fuel filler port comprising:

the gravity oil filling port is arranged at the top of the tail oil tank; and

and the pressure oil filling port is arranged at the bottom of the tail oil tank.

4. The uncontrolled strategic fuel tank for supersonic unmanned aerial vehicles of claim 3 wherein the pressure port is disposed on a branch of the fuel supply line and a one-way valve is disposed on the branch.

5. The unmanned tactical fuel tank for supersonic drones of claim 1, further comprising:

the oil return pipe is arranged on a branch of the oil supply pipe and is used for conveying the fuel oil in the oil supply pipe back to the head oil tank;

and the oil return pipe is provided with a pressure relief valve which is opened when the pressure in the oil supply pipe reaches a set value.

6. The uncontrolled strategic fuel consumption tank suitable for supersonic unmanned aerial vehicle of claim 1, wherein the fuel supply line is provided with a fuel pump for pumping fuel out of the tail tank.

7. The uncontrolled strategic fuel tank suitable for supersonic drones of claim 1, wherein the tail tank has a fuel level sensor disposed therein for monitoring the fuel level in the tail tank.

8. The unmanned tactical fuel tank for supersonic drones of claim 7, said fuel level sensor for monitoring the fuel level in said tail tank after exhaustion of fuel in said head tank and said middle tank.

9. The uncontrolled strategic fuel tank for supersonic drones of claim 1, wherein the bottoms of the head tank, the middle tank and the tail tank are provided with oil drains.

10. A supersonic drone having disposed within the drone body an uncontrolled tactical fuel tank as described in any of claims 1 to 9 for a supersonic drone.