CN116533696A - Cross-medium aircraft power device and working method thereof - Google Patents

Abstract

The invention discloses a cross-medium aircraft power device and a working method thereof, and the technical scheme is that the cross-medium aircraft power device comprises a duct lip; a medium-crossing motor is arranged in the duct lip, and comprises a front motor and a rear motor; the front motor is internally provided with a water-driven propeller, and the water-driven propeller is used for providing underwater thrust when the aircraft is underwater; the rear motor is arranged on one side of the front motor, one side, deviating from the front motor, of the rear motor is connected with a pneumatic propeller, and the pneumatic propeller is used for providing air thrust when the aircraft flies in the air. The invention relates to a cross-medium aircraft power device and a working method thereof, which have the effects of realizing that an aircraft can navigate across medium and reducing resistance in the navigation process by taking a double-rotor motor, a pneumatic propeller and a water-driven propeller as power devices.

Description

A trans-medium aircraft power device and its working method

technical field

The invention relates to the field of aircraft technology, and more specifically relates to a trans-medium aircraft power device and a working method thereof.

Background technique

The trans-media aircraft refers to the aircraft that crosses the air/water two-phase interface and flies or sails from the air into the water or from the water into the air. It is a typical trans-medium aircraft that performs tasks such as alert investigation, defense penetration operations, communication relay or resource exploration, water quality monitoring, and search and rescue at sea, such as submarine-launched missiles and anti-submarine torpedoes. Trans-medium aircraft has broad prospects for both military and civilian use and has been paid more and more attention.

As a new concept aircraft, the power system of the trans-medium aircraft is one of the core issues in the research and development of the trans-medium aircraft. To realize air flight and underwater navigation, the power system must have the ability to continuously switch between the two media. However, due to the large gap between the physical properties of water and air, its dynamic characteristics are significantly different from those of traditional aircraft. The power system of existing trans-medium aircraft is a combination of air power system and water power system. In general, two sets of power system solutions are feasible, but for small trans-medium aircraft, its volume and weight cannot bear two sets of independent power systems. This paper will propose an integrated trans-medium power system, which takes into account both volume and weight, and can be used on small-scale trans-medium aircraft.

According to the resistance formula Resistance is related to drag coefficient, density, and forward speed, etc. The value of resistance is not only related to the properties of the medium but also related to a series of requirements such as the properties and temperature of the object, but the density of water is 772 times that of air. In comparison, the resistance of the same object in water is much greater than that in air. If the same type of propeller is used in water and in the air, when the propeller in the air is used in water, in order to overcome the resistance in the water, the speed of the propeller must increase, but the propeller As the rotational speed increases, the resistance in the water will also increase. For the shape of the propeller, due to the high resistance of water, the speed of the marine propeller will not be very high. Only by making the blades of the propeller larger can the greater thrust be obtained. However, the density of air is much smaller than that of water. Aeroengines The only way to get more thrust is to increase the speed, but the large blades cannot withstand the pressure brought by the high speed, so the hydrodynamic propeller and the aerodynamic propeller cannot use the same type of blade. Aircraft power plant needs to be solved urgently.

Contents of the invention

In view of the deficiencies in the prior art, the object of the present invention is to provide a power device for a cross-medium aircraft and its working method, which has a dual-rotor motor, an aerodynamic propeller and a hydrodynamic propeller as power devices, so that the aircraft can sail across the medium and reduce the The effect of little drag during sailing.

To achieve the above object, the present invention provides the following technical solutions:

A power plant for a trans-medium aircraft, comprising:

duct lip;

A cross-medium motor is arranged in the lip of the duct, and the cross-medium motor includes a front motor and a rear motor;

The front motor is provided with a hydrodynamic propeller, and the hydrodynamic propeller is used to provide underwater thrust when the aircraft is underwater;

The rear motor is arranged on one side of the front motor, and the side of the rear motor facing away from the front motor is connected with an air propeller, which is used to provide air thrust when the aircraft is flying in the air.

As a further improvement of the present invention, the front motor includes a front motor stator and a front motor rotor, the rear motor includes a rear motor stator and a rear motor rotor, the front motor stator is fixedly connected to the rear motor stator, and the front motor includes The front outer end block and the front inner end block, the rear motor includes the rear inner end block, the front motor bearing is installed between the front outer end block and the front motor rotor, and the front motor rotor and the front motor stator are also A front motor bearing is installed, a rear motor bearing is installed between the rear inner end block and the rear motor rotor, and a rear motor bearing is also installed between the rear motor rotor and the rear motor stator.

As a further improvement of the present invention, a stator connection block is further arranged between the front motor rotor and the rear motor rotor.

As a further improvement of the present invention, the hydrodynamic propeller is arranged between the front motor rotor and the front lower end block, and the position between the hydrodynamic propeller and the front motor rotor is keyed so that when the aircraft is underwater, The motor rotor rotates to drive the hydrodynamic propeller to generate underwater thrust.

As a further improvement of the present invention, the rear motor rotor is equipped with a propeller clip, and the aerodynamic propeller is installed in the propeller clip, so that when the aircraft is in the air, the rear motor rotor rotates to drive the aerodynamic propeller to rotate to generate air thrust.

As a further improvement of the present invention, a limiter is also provided on the paddle clamp, and the limiter is used to limit the air propeller.

As a further improvement of the present invention, the aerodynamic propeller and the paddle clamp are rotatably connected by plugging bolts.

As a further improvement of the present invention, it also includes a controller, which is configured with a design strategy for the blade shape design of the aerodynamic propeller, and the design strategy includes the following steps:

S1: Determine the design parameters of the blades in the aerodynamic propeller. The design parameters include: the number of blades, the radius of the propeller, the radius of the hub, the micro-end of the blade, the required pulling force of the propeller, the flight speed, the speed of the propeller, and the flight height. Air density and loss coefficient;

S2: Calculate the Lagrangian multiplier k, the specific integral equation is as follows.

In the formula: Kp is the correction factor;

S3: In order to calculate the chord length bi and the pitch angle of the i-th section, first calculate the incoming flow angle of the blade element and the induced velocity angle of attack, and the specific calculation formula is as follows:

S4: Use profili or xflr software to calculate the aerodynamic angle of attack α _max at the maximum lift-drag ratio of the specified airfoil, as well as the lift coefficient C _lmax and drag coefficient C _dmax at this time;

S5: Calculate the chord length bi and the pitch angle of the i-th section, the calculation formula is as follows:

θ = β _* + α _max

S6: Repeat the fourth step to calculate the chord length and pitch angle of all blade micro-segments;

S7: Calculate the pulling force, resistance, torque and power of each blade element segment and add them together to obtain the efficiency of the propeller.

As a further improvement of the present invention, the step S7 is specifically:

The lift and drag acting on a single blade element are:

In the formula, C _l and C _d are the lift coefficient and drag coefficient of the airfoil, w is the resultant velocity of the flow to the blade airfoil, b is the chord length of the blade element, and dr is the micro-section of the blade element;

The blade element pulling force, rotational resistance, effective power and required power are:

dT=dLcosβ _* -dDsinβ _*

dQ＝dDcosβ _* +dLsinβ _*

dP _yx =(dLcosβ _* -dDsinβ _* )*V

dP＝(dDcosβ _* +dLsinβ _* )*Ωr

In the formula, β _* is the incoming flow angle of the blade element, V is the inflow velocity of the propeller, and Ωr is the rotational linear velocity of the blade element position. Since the inflow velocity is often much greater than the induced velocity at the design speed point of the aerodynamic propeller, the induced velocity in the incoming flow of the blade element is ignored. speed, that is:

Arranging the above formula, the efficiency of leaf element can be obtained as:

In the formula, C _l /C _d is the lift-to-drag ratio of the airfoil.

A working method of a power plant for a cross-medium aircraft, providing the power plant for a cross-medium aircraft as described above:

When the aircraft is in the air medium, the controller controls the aerodynamic propeller to open, and switches the motor to work to drive the aerodynamic propeller to rotate to provide air thrust for the aircraft;

When the aircraft crosses the medium into the water, the controller switches the front motor to work to drive the hydrodynamic propeller to provide the aircraft with water thrust;

The front lip of the duct rectifies the aircraft.

Beneficial effects of the present invention:

1. The cross-medium power system is adopted. The design of the cross-medium motor is an integrated design of double-rotor motors. The new power system has the disadvantages of heavy weight, complex structure and low efficiency;

2. The overall cross-media power device adopts the mode of coaxial double propellers, and the power can be switched freely underwater and in the air. The ducted shaftless hydrodynamic propeller can reduce the kinetic energy loss at the propeller shaft, and the aerodynamic propeller can be used underwater The foldable advantage can reduce the resistance of water navigation and improve the propulsion efficiency of hydrodynamic propellers;

3. The design of the front lip of the duct and the design of the aerodynamic propeller improve the effect of the aerodynamic propeller in providing air thrust in the air.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the present invention;

Fig. 2 is a side view of the motor of the present invention;

Fig. 3 is a sectional view of the motor of the present invention;

Fig. 4 is the enlarged view of the cross-sectional view of the motor of the present invention;

Fig. 5 is a schematic diagram of the folding state of the pneumatic propeller of the present invention;

Fig. 6 is the stress analysis diagram embodying leaf element;

Fig. 7 is a modeling and rendering diagram embodying the rotor structure;

Fig. 8 is the computational design flow chart that embodies aerodynamic propeller;

Fig. 9 is a symmetrical cross-sectional pressure cloud diagram of the hydrodynamic propeller in the working state of the present invention;

Fig. 10 is a cloud diagram of the pressure coefficient of the symmetrical section of the aerodynamic propeller in the working state of the present invention.

Reference signs: 1. Front motor; 2. Rear motor; 3. Duct lip; 4. Front motor rotor; 5. Front motor stator; 6. Rear motor rotor; 7. Rear motor stator; 8. Front outer end 9. Front inner end block; 10. Rear inner end block; 11. Plug bolt; 12. Propeller clamp; 13. Stator connection block; 14. Pneumatic propeller; 15. Limiter; 16. Hydrodynamic propeller; 17. Key; 18. Front motor bearing; 19. Rear motor bearing.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments. Wherein the same components are denoted by the same reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to the directions in the drawings, and the words "bottom" and "top "Face", "inner" and "outer" refer to directions toward or away from, respectively, the geometric center of a particular component.

Referring to Figures 1 to 10, it is a specific embodiment of a cross-medium aircraft power device and its working method of the present invention, including a duct lip 3 and a cross-medium motor, and the cross-medium motor is arranged on the duct lip 3, the trans-medium motor includes a front motor 1 and a rear motor 2, the front motor 1 is provided with a hydrodynamic propeller 16, and the hydrodynamic propeller 16 is used to provide underwater thrust when the aircraft is underwater. The rear motor 2 is arranged on one side of the front motor 1, and the side of the rear motor 2 away from the front motor 1 is connected with an air propeller 14, and the air propeller 14 is used to provide air thrust when the aircraft is flying in the air.

Described front motor 1 comprises front motor stator 5 and front motor stator 4, and described rear motor 2 comprises rear motor stator 7 and rear motor rotor 6, and described front motor stator 5 is fixedly connected with rear motor stator 7, and described front motor 1 includes a front outer end block 8 and a front inner end block 9, the rear motor 2 includes a rear inner end block 10, a front motor bearing 18 is installed between the front outer end block 8 and the front motor stator 4, the front Front motor bearing 18 is also housed between motor stator 4 and front motor stator 5, rear motor bearing 19 is housed between described rear inner end block 10 and rear motor rotor 6, described rear motor rotor 6 and rear motor stator 7 A rear motor bearing 19 is also installed between them, a stator connection block 13 is also arranged between the front motor stator 4 and the rear motor rotor 6, and a rotor structure is also arranged between the pneumatic propeller 14 and the duct lip 3, The rotor structure includes an inner rotor and an outer rotor. The arrangement of the inner rotor and the outer rotor reduces the resistance of the aerodynamic propeller 14 during operation and provides efficient driving for the aerodynamic propeller 14 .

The hydrodynamic propeller 16 is arranged between the front motor stator 4 and the front lower end block, and the key 17 is positioned between the hydrodynamic propeller 16 and the front motor stator 4, so that when the aircraft is underwater, the front motor stator 4 Rotate to drive the hydrodynamic propeller 16 to generate underwater thrust.

Propeller clamp 12 is housed on the described rear motor rotor 6, and described aerodynamic propeller 14 is installed in the propeller clamp 12, so that when the aircraft is in the air, the rotation of the rear motor rotor 6 drives the rotation of the aerodynamic propeller 14 to generate thrust in the air. The paddle clamp 12 is also provided with a limiter 15, and the limiter 15 is used to limit the position of the pneumatic propeller 14, and the pneumatic propeller 14 and the paddle clamp 12 are connected by plug bolts 11 so that when entering the water , the aerodynamic propeller 14 is shrunk to a state where the axis of the duct lip 3 is parallel.

The trans-medium aircraft power device also includes a controller, and the controller is configured with a design strategy for blade shape design of the aerodynamic propeller, and the design strategy includes the following steps:

S1: Determine the design parameters of the blades in the aerodynamic propeller. The design parameters include: the number of blades, the radius of the propeller, the radius of the hub, the micro-end of the blade, the required pulling force of the propeller, the flight speed, the speed of the propeller, and the flight height. Air density and loss coefficient;

S2: Calculate the Lagrangian multiplier k, the specific integral equation is as follows.

In the formula: Kp is the correction factor;

S3: In order to calculate the chord length bi and the pitch angle of the i-th section, first calculate the incoming flow angle of the blade element and the induced velocity angle of attack, and the specific calculation formula is as follows:

S4: Use profili or xflr software to calculate the aerodynamic angle of attack α _max at the maximum lift-drag ratio of the specified airfoil, as well as the lift coefficient C _lmax and drag coefficient C _dmax at this time;

S5: Calculate the chord length bi and the pitch angle of the i-th section, the calculation formula is as follows:

θ = β _* + α _max

S6: Repeat the fourth step to calculate the chord length and pitch angle of all blade micro-segments;

S7: Calculate the pulling force, resistance, torque and power of each blade element segment and add them together to obtain the efficiency of the propeller.

As a further improvement of the present invention, the step S7 is specifically:

The lift and drag acting on a single blade element are:

In the formula, C _l and C _d are the lift coefficient and drag coefficient of the airfoil, w is the resultant velocity of the flow to the blade airfoil, b is the chord length of the blade element, and dr is the micro-section of the blade element;

The blade element pulling force, rotational resistance, effective power and required power are:

dT=dLcosβ _* -dDsinβ _*

dQ＝dDcosβ _* +dLsinβ _*

dP _yx =(dLcosβ _* -dDsinβ _* )*V

dP＝(dDcosβ _* +dLsinβ _* )*Ωr

In the formula, β _* is the incoming flow angle of the blade element, V is the inflow velocity of the propeller, and Ωr is the rotational linear velocity of the blade element position. Since the inflow velocity is often much greater than the induced velocity at the design speed point of the aerodynamic propeller, the induced velocity in the incoming flow of the blade element is ignored. speed, that is:

Arranging the above formula, the efficiency of leaf element can be obtained as:

In the formula, C _l /C _d is the lift-to-drag ratio of the airfoil.

After the controller completes the design of the aerodynamic propeller 14, a control information table is formed, which is used to control the operation of the front motor 1 or the rear motor 2 under different media based on the control information table to switch the flight mode of the aircraft.

The working method of the cross-medium aircraft power plant provides the above-mentioned cross-medium aircraft power plant:

When the aircraft is in the air medium, the controller controls the aerodynamic propeller 14 to open and switch, and the motor 2 works to drive the aerodynamic propeller 14 to rotate to provide air thrust for the aircraft;

When the aircraft crosses the medium into the water, the controller switches the front motor 1 to work to drive the hydrodynamic propeller 16 to provide thrust in water for the aircraft;

The front lip of the duct rectifies the aircraft.

Working principle and its effect:

The front motor 1 is composed of the front motor stator 5 and the front motor rotor 4, the rear motor 2 is composed of the rear motor rotor 6 and the rear motor stator 7, and the front motor stator 5, the front outer end block 8 and the stator connection block 13 pass through The bolt is fixedly connected, and the front motor bearing 18 is housed between the front outer end block 8 and the front motor rotor 4, and the front motor bearing 18 is also housed between the stator connection block 13 and the front motor rotor 5, and the hydrodynamic propeller 16 and the front motor rotor 4 are fixed by key 17, front motor bearing 18 and front motor rotor 4 fronts are equipped with front inner end block 9, front inner end block 9 is to prevent the front motor bearing 18 from being thrown out in the way of work, the stator connecting block 13, the rear motor The stator 7 and the rear inner end block 10 are fixedly connected by bolts, a rear motor bearing 19 is installed between the stator connection block 13 and the rear motor rotor 6, and a rear motor bearing 19 is installed between the rear inner end block 10 and the rear motor rotor 6. Motor bearing 19, back inner end block 10 is to throw back motor bearing 19 in order to prevent back motor 2 working way.

The duct lip 3 is installed on the front of the front outer end block 8 and fixed by gluing. The paddle clamp 12 is fixed on the rear motor rotor 6 by bolts. A limiter 15 is also installed on the top, and after the pneumatic propeller 14 is folded backward, the limiter 15 plays a position-limiting effect, so that the pneumatic propeller 14 is folded in a designated position.

The trans-medium aircraft power device in this application is divided into two working states, underwater working state and aerial working state. In the underwater working state, the aerodynamic propeller 14 is folded backwards, the position is limited by the stopper 15, and the front motor 1 works , the front motor rotor 4 rotates to drive the hydrodynamic propeller 16 to rotate to provide underwater thrust; during the air working state, the pneumatic propeller 14 is opened, the rear motor 2 works, and the rear motor rotor 6 rotates to drive the pneumatic propeller to rotate to provide air thrust.

The above descriptions are only preferred implementations of the present invention, and the scope of protection of the present invention is not limited to the above examples, and all technical solutions that fall under the idea of the present invention belong to the scope of protection of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principles of the present invention should also be regarded as the protection scope of the present invention.

Claims (10)

1. A cross-medium aircraft power plant, comprising:

a bypass lip (3);

a medium-crossing motor is arranged in the duct lip (3), and comprises a front motor (1) and a rear motor (2);

a water-driven propeller (16) is arranged in the front motor (1), and the water-driven propeller (16) is used for providing underwater thrust when the aircraft is underwater;

the rear motor (2) is arranged on one side of the front motor (1), one side, deviating from the front motor (1), of the rear motor (2) is connected with a pneumatic propeller (14), and the pneumatic propeller (14) is used for providing air thrust when the aircraft flies in the air.

2. A cross-medium aircraft power plant according to claim 1, characterized in that: front motor (1) includes front motor stator (5) and front motor rotor (4), back motor (2) include back motor stator (7) and back motor rotor (6), front motor stator (5) and back motor stator (7) rigid coupling, front motor (1) include outer end block (8) and interior end block (9) in front, back motor (2) include interior end block (10) in the back, front motor bearing (18) are equipped with between outer end block (8) in the front and front motor rotor (4), front motor bearing (18) are also equipped with between front motor rotor (4) and front motor stator (5), back motor bearing (19) are equipped with between back interior end block (10) and back motor rotor (6), back motor bearing (19) are also equipped with between back motor rotor (6) and back motor stator (7).

3. A cross-medium aircraft power plant according to claim 2, characterized in that: a stator connecting block (13) is further arranged between the front motor rotor (4) and the rear motor rotor (6).

4. A cross-medium aircraft power plant according to claim 2, characterized in that: the water-driven propeller (16) is arranged between the front motor rotor (4) and the front lower end block, and the water-driven propeller (16) and the front motor rotor (4) are positioned through a key (17), so that when the aircraft is underwater, the front motor rotor (4) rotates to drive the water-driven propeller (16) to generate underwater thrust.

5. A cross-medium aircraft power plant according to claim 4, characterized in that: the rear motor rotor (6) is provided with a paddle clamp (12), and the air-driven propeller (14) is arranged in the paddle clamp (12) so that when the aircraft is in the air, the rear motor rotor (6) rotates to drive the air-driven propeller (14) to rotate to generate air thrust.

6. A cross-medium aircraft power plant according to claim 5, characterized in that: the propeller clamp (12) is also provided with a limiter (15), and the limiter (15) is used for limiting the pneumatic propeller (14).

7. A cross-medium aircraft power plant according to claim 5, characterized in that: the pneumatic propeller (14) is rotationally connected with the propeller clamp (12) through a plugging bolt (11).

8. A cross-medium aircraft power plant according to claim 7, characterized in that: the method further comprises a controller, wherein a design strategy for blade-shaped design of the aerodynamic propeller is configured in the controller, and comprises the following steps of:

s1: determining design parameters of blades in an aerodynamic propeller, the design parameters comprising: the number of the blades, the radius of the propeller, the radius of the hub, the micro-ends of the blades, the required pulling force of the propeller, the flying speed, the rotating speed of the propeller, the air density of the flying height and the loss coefficient;

s2: the lagrangian multiplier k is calculated and the specific integral equation is shown below.

Wherein: kp is a correction factor;

s3: in order to calculate the chord length bi and the pitch angle of the ith section, the incoming flow angle and the induced speed attack angle of the phyllin are calculated, and the specific calculation formula is as follows:

s4: calculation of specified airfoil maximum lift-drag ratio using profile or xflr softwarePneumatic angle of attack alpha _max And the lift coefficient C at that time _lmax Coefficient of resistance C _dmax ；

S5: the chord length bi and pitch angle of the ith section are calculated as follows:

θ＝β _* +α _max

s6: the fourth step is repeated to calculate the chord length and pitch angle of all the blade micro-segments;

s7: and calculating the tension, resistance, torque and power of each leaf element micro-segment, adding the calculated tension, resistance, torque and power, and finally obtaining the efficiency of the propeller.

9. A cross-medium aircraft power plant according to claim 8, characterized in that: the step S7 specifically includes:

the lift and drag forces acting on individual phyllins are:

wherein C is _l 、C _d The wing profile lift coefficient and the drag coefficient are represented by w, the sum speed of the wing profile flowing to the blade, b, the chord length of the phyllostachys, and dr, the phyllostachys micro-segment;

the leaf extract tension, rotation resistance, effective power and required power are as follows:

dT＝dLcosβ _* -dDsinβ _*

dQ＝dDcosβ _* +dLsinβ _*

dP _yx ＝(dLcosβ _* -dDsinβ _* )*V

dP＝(dDcosβ _* +dLsinβ _* )*Ωr

wherein beta is _* For the incoming flow angle of the phyllanthin, V is the inflow speed of the propeller, Ω is the rotational linear speed of the phyllanthin position, and because the inflow speed is often far greater than the induction speed at the speed point of the aerodynamic propeller design, the induction speed in the incoming flow of the phyllanthin is ignored, namely:

the above formula is arranged to obtain the leaf extract with the following efficiency:

wherein C is _l /C _d Is the lift-drag ratio of the wing profile.

10. A method of operating a cross-medium aircraft power plant, providing a cross-medium aircraft power plant as claimed in any one of claims 1 to 9, characterized in that:

when the aircraft is in an air medium, the controller controls the pneumatic propeller (14) to be opened, and the motor (2) is switched to work to drive the pneumatic propeller (14) to rotate so as to provide air thrust for the aircraft;

when the aircraft crosses the medium into the water, the controller switches the front motor (1) to work so as to drive the water-driven propeller (16) to provide the water thrust for the aircraft;

the ducted front lip rectifies the aircraft.