CN215814715U - Piston screw side effect demonstration teaching aid - Google Patents

Abstract

The utility model discloses a piston propeller side effect demonstration teaching aid, which comprises: the airplane model with the propeller, the motor, the elevator, the rudder, the force measuring balance, the double-shaft turntable, the support, the wind speed generating device and the smoke. The device can visually observe the generation and the effect of side effects such as piston propeller slip flow, reaction moment, precession, airflow oblique blowing and the like, the direction and the pitching moment of the force measuring balance are gradually zero by continuously adjusting the angles of the rudder and the elevator, how to correct and eliminate the influence caused by the slip flow is demonstrated, the piston propeller reaction moment is demonstrated by positively and negatively rotating the motor and force measuring balance data, the precession phenomenon and the influence in flight are demonstrated by the visual movement of an airplane model on the double-shaft turntable, and the airflow oblique blowing effect is demonstrated by colored smoke and the force measuring balance data. The teaching aid combines theory and practice, and obviously improves the teaching effect. The teaching aid also has the advantages of convenient observation, good demonstration effect, low cost, simple operation, good portability and the like.

Description

Piston screw side effect demonstration teaching aid

Technical Field

The utility model belongs to the field of teaching of airplane aerodynamics and flight mechanics, relates to simulation demonstration which is an important means for teaching and researching airplane aerodynamics and flight mechanics, and particularly relates to a demonstration teaching aid for side effects of a piston propeller.

Background

The simulation demonstration is an important teaching means for enhancing the intuitive and perceptual knowledge of the trainees. The simulation demonstration is to realize the reality. Due to objective reasons, flight trainees can not visually describe some important phenomena occurring when the airplane actually flies in classroom teaching, the videos are watched without substitution feeling, independent experimental teaching or observation is difficult to guarantee in time and effect, and simulation demonstration can combine classroom teaching and instant teaching for some important flying phenomena, concepts and definitions. Propeller type aircraft have four side effects in actual flight: slipstream, reaction torque, precession, and air flow blowing at an angle. The slipstream refers to airflow which is stirred by a propeller to accelerate and twist backwards, the airflow has great influence on the actual flight of the airplane, the propellers have different turning directions and different influences on the flight, and the adverse effects caused by the slipstream of the propeller can be eliminated by needing corresponding control, for example, a certain early education machine needs to pedal a left rudder to correct the course during take-off and running due to the slipstream of the propeller. The propeller generates rotation resistance in rotation, and the moment formed by the rotation resistance on the propeller shaft is the reaction moment of the propeller, and the moment is transmitted to the airplane through the transmitter, so that the airplane inclines to the opposite direction of the rotation of the propeller. For a propeller type airplane, when the airplane rotates in a pitching manner or deflects, namely when the direction of a propeller shaft changes, a gyroscopic moment is generated due to the gyroscopic effect of a propeller, so that a nose rotates around another shaft, and the phenomenon is precession of the propeller. When the propeller type airplane flies, the flying speed direction is not parallel to the propeller shaft direction and the air flow blows to the propeller obliquely, the phenomenon is called as air flow oblique blowing, and under the condition of air flow oblique blowing, the propeller can generate a pulling force moment and a side force moment and has certain influence on the flying. Flight trainees lack actual flight training during school, and the knowledge of many flight phenomena mainly stays in a theoretical level, although the subsequent flight training is set, the culture time is increased invisibly. In the traditional classroom teaching, the students see or hear video animation or theoretical explanation, and the piston type propeller side effect is difficult to be intuitively known and sensed. On-site teaching is limited in time and poor in theoretical effect.

Therefore, how to design a piston type propeller side effect demonstration teaching aid which is simple, feasible, convenient and easy to use, visual in demonstration effect and good in demonstration method has important significance.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a piston type propeller side effect demonstration teaching aid which is not only suitable for classroom demonstration teaching, but also has practical values of reference and reference for science popularization teaching and the like.

In order to solve the contradiction and the problem existing in the traditional classroom teaching and the field teaching, better for war foretell, shorten talent culture time, the utility model provides a piston propeller side effect demonstration teaching aid, which comprises: the airplane model with the propeller comprises an airplane model, a motor, an elevator, a rudder, a force measuring balance, a double-shaft turntable, a support, a wind speed generating device and smoke, wherein the motor is fixed in the airplane model, the elevator is connected with a horizontal stabilizing surface of the airplane model, the rudder is connected with a vertical stabilizing surface of the airplane model, the angles of the elevator and the rudder after installation are adjustable, the force measuring balance is connected with the airplane model and the double-shaft turntable, the force measuring balance can measure acting force applied to the airplane model and moment of the airplane model, the double-shaft turntable is connected with the support, the double-shaft turntable is provided with a locking device, the wind speed generating device is arranged in front of the propeller, and colored smoke is arranged between the wind speed generating device and the propeller. Through the teaching aid, the generation and the effect of side effects such as slipstream, reaction moment, precession, airflow inclined blowing and the like of the piston type propeller plane during actual flight can be simulated and demonstrated, corresponding theoretical explanation is combined, a student can deeply recognize the principle of the side effect of the piston type propeller, and a good foundation is laid for subsequent flight.

Preferably, the motor is speed adjustable. The motor rotating speed is adjustable, so that the device is closer to actual flight during simulation and demonstration, the steering is adjustable, actual flight of different turning types can be demonstrated through one set of device, and students can deeply understand the generation and action principle of the piston type propeller side effect through turning comparison. Adopt small-size or micro-motor, on the one hand can effectively reduce cost, in addition still consider the portability when using as the teaching aid.

Preferably, the aircraft body is hollow. The aircraft model is hollow, and not only can the dismouting motor swiftly, can alleviate model weight moreover, portable also is convenient for realize the modularization equipment.

Preferably, the motor is arranged in the airplane model, so that the appearance of the assembled whole model accords with an actual propeller type airplane, the interference of the motor to the airflow can be eliminated, and the demonstration effect can accord with actual flight more.

Preferably, the rudder angle is adjustable. The propeller slip flow can influence the pitching balance of the airplane, and by adjusting the angle of the elevator, the method can demonstrate how to eliminate the influence of the propeller slip flow on the pitching balance in the process of adjusting the angle of the elevator, and can explain the corresponding operation of the push rod and the pull rod by combining the rudder deflection angle, thereby laying a foundation for subsequent actual flight and operation.

Preferably, the rudder angle is adjustable. The propeller slipstream mainly influences the directional balance of the airplane, and by adjusting the rudder angle, the influence of the propeller slipstream on the directional balance can be demonstrated and eliminated in the process of adjusting the rudder angle, and the left-hand pedaling operation and the right-hand pedaling operation can be taught by combining the rudder deflection angle, so that the foundation is laid for better and faster subsequent flight entering.

Preferably, the force balance is a device for measuring force and moment, the airplane can not only have various aerodynamic forces but also have moment under the action of the aerodynamic forces when flying, the aerodynamic forces generated by the side effect of the propeller can generate moment when acting on the airplane model, for example, slip flow can generate pitching and directional moment, reaction moment can generate the effect of rolling the airplane, the moment just influences the balance of the airplane, the principle of the generation of various side effects is displayed through the data of the force balance and the intuitive model motion, and the knowledge understanding and the application of a student are deepened.

Preferably, the two-axis turntable is provided with a locking device. The double-shaft turntable is provided with certain damping, so that the airplane model and the force measuring balance are prevented from rotating after being installed, but after the motor and the wind speed generating device are started, the locking device of the double-shaft turntable mainly ensures the platform stability during demonstration of phenomena of slipstream, airflow inclined blowing and reaction torque, and the result is more scientific and reasonable.

Preferably, the wind speed generating device is a speed-adjustable wind speed generating device. The wind speed generating device is specifically a small miniature axial flow fan or a small miniature centrifugal fan, and the small miniature axial flow fan or the small miniature centrifugal fan is adopted, so that on one hand, the cost can be effectively reduced, and in addition, the portability when the wind speed generating device is used as a teaching aid is also considered. Of course, an air speed generator such as an electric fan may be used.

Preferably, the smoke is coloured. The slipstream and the air current oblique blowing generated when the propeller type airplane actually flies can lead the airplane to be subjected to corresponding acting force, which can be seen on a force measuring balance, and the colored smoke applied in the incoming flow can help students to have more intuitive understanding on the twisted and oblique air current.

According to the piston type propeller side effect demonstration teaching aid, the moment data of the force measuring balance is combined with the flow of colored smoke, so that a student can understand the reason of the propeller slipstream side effect during actual flight, and the slipstream influence is gradually corrected and eliminated through the angle adjustment of the elevator and the rudder, so that the student can deeply understand the coordinated operation of the rod rudder during actual flight. The generation and the influence of the reaction moment of the propeller are displayed by positively and negatively rotating the motor and measuring force balance data, so that a student can understand designs such as an actual aircraft tail rotor wing or gravity center offset more deeply. The precession phenomenon and influence of the propeller-driven aircraft in flight are demonstrated through the intuitive movement of the aircraft model on the double-shaft turntable during pitching or yawing. And demonstrating the effect and influence of the oblique blowing of the airflow through the data of the colored smoke and the force measuring balance. The teaching aid combines theory and practice, and obviously improves the teaching effect. The simulation demonstration piston type propeller slip flow, reaction moment, precession, airflow inclined blowing and other side effects can be well simulated, the effect is good, the simulation demonstration piston type propeller slip flow, reaction moment, precession, airflow inclined blowing and other side effects are convenient to observe, the demonstration piston type propeller slip flow, the airflow inclined blowing and other side effects are good, the simulation piston type propeller slip flow, the demonstration piston type propeller inclined blowing and airflow inclined blowing air flow simulation teaching aid has the advantages of being good in demonstration effect, low in cost, simple to operate, good in portability and the like, and can well meet teaching requirements.

Drawings

Fig. 1 is a schematic diagram of a piston type propeller side effect demonstration teaching aid.

Detailed Description

The following describes the embodiments of the present invention with reference to the accompanying drawings.

Example 1

The utility model provides a piston screw side effect demonstration teaching aid, as shown in figure 1, specifically includes: the airplane model comprises an airplane model 2 provided with a propeller 1, a motor 3, an elevator 4, a rudder 5, a force measuring balance 6, a double-shaft turntable 7, a support 8, a wind speed generating device 9 and smoke 10, wherein the propeller 1 is connected with the motor 3, the motor 3 is fixed in the airplane model 2, the elevator 4 is connected with a horizontal stabilizing plane of the airplane model 2, the rudder 5 is connected with a vertical stabilizing plane of the airplane model 2, the force measuring balance 6 is connected with the airplane model 2 and the double-shaft turntable 7, the double-shaft turntable 7 is connected with the support 8, the wind speed generating device 9 is arranged in front of the propeller 1, and the smoke 10 is arranged between the wind speed generating device 9 and the propeller 1. The wind speed generating device 9 adopts a small centrifugal fan.

During simulation demonstration, the biaxial turntable is locked and fixed or the force measuring balance is directly connected with the support, and the elevator and the rudder are fixed in angle to be respectively positioned on the same plane with the horizontal stabilizing plane and the vertical stabilizing plane of the airplane model. The wind speed generating device is placed in front of the propeller, so that the axis of an outlet of the wind speed generating device is collinear with the central line of a rotating shaft of the motor, the rotating speed of the motor and the rotating direction of the motor are continuously adjusted to simulate the increase and decrease of an accelerator and the downward rotation of different propellers during actual flight, the influence and the performance of the slipstream of the propellers are simulated, smoke is released right ahead of the propellers, the visual phenomenon of the slipstream is observed, and meanwhile, the relevant data of the force measuring balance, especially the change of the direction moment and the pitching moment, are observed, so that the principle generated by the slipstream and the influence on the flight are better understood. And then continuously adjusting the elevator and the rudder to gradually make the pitching moment and the directional moment of the force-measuring balance zero, demonstrating how to eliminate the adverse effect of slipstream on the flight in the actual flight, and deepening the deep cognition of the trainee on the flight by combining theoretical explanation.

Example 2

A piston screw side effect demonstration teaching aid in this embodiment, the structure is the same basically with embodiment 1, and the main difference lies in: (1) the angle of the elevator 4 is fixed in the whole simulation demonstration process; (2) the angle of the rudder 5 is fixed in the whole simulation demonstration process; (3) smoke 10 is not released in the simulation demonstration process; (4) the wind speed generating device 8 adopts a miniature axial flow fan, so that the size of the fan can be further reduced, and the maximum wind speed of the fan can be improved.

During simulation demonstration, the outlet center line of the wind speed generating device and the center line of the rotating shaft of the propeller are collinear, the outlet wind speed and the rotating speed of the motor are continuously adjusted, the change of the moment of the force measuring balance around the longitudinal axis of the aircraft body, namely the rolling moment, is observed, and by combining the modes of gravity center offset, additional installation of a rotor wing at the tail part and the like adopted during aircraft design, a student can clearly understand the reaction moment of the piston type propeller aircraft during actual flight.

Example 3

A piston screw side effect demonstration teaching aid in this embodiment, the structure is the same basically with embodiment 2, and the main difference lies in: (1) the angle of the elevator 4 needs to be adjusted in time in the simulation demonstration process; (2) the angle of the rudder 5 needs to be adjusted in time in the simulation demonstration process; (3) the locking device of the double-shaft turntable 7 is opened; (4) the airplane model 2 needs to be controlled in pitching and yawing in the whole simulation demonstration process.

During simulation and demonstration, the center line of the outlet of the wind speed generating device is collinear with the center line of the rotating shaft of the propeller, the double-shaft rotating platform has certain damping, and the airplane model cannot automatically rotate around a certain shaft. However, after the wind speed generating device and the motor are started, pitching and direction (yaw) moments can occur due to the influence of the slip flow, and in order to ensure the accuracy of simulation demonstration, the elevator and the rudder are adjusted before pitching and yaw operation is carried out on the airplane model, so that the interference moment generated by the slip flow is eliminated. When the airplane model is subjected to pitching operation, the movement of the model around the vertical shaft of the airplane is noticed, the change of the moment in the direction of the force measuring balance is observed at the same time, and when the yawing operation is carried out, the movement of the flying model around the horizontal shaft and the change of the pitching moment are noticed. Through the data of the force measuring balance and the visual motion of the model, the trainee can deeply understand and recognize the precession of the piston type propeller aircraft, and a good foundation is laid for future flight.

Example 4

A piston screw side effect demonstration teaching aid in this embodiment, the structure is the same basically with embodiment 3, and the main difference lies in: (1) locking the double-shaft turntable 7; (2) the airplane model 2 does not need to be subjected to pitching and yawing control in the whole simulation demonstration process; (3) the wind speed generating device 9 is not parallel and collinear with the central line of the rotating shaft of the propeller 1; (4) the simulated demonstration requires release of smoke 10.

During simulation demonstration, the outlet center line of the wind speed generating device and the center line of the propeller rotating shaft are collinear, pitching and directional moments can occur due to the influence of slip flow after the wind speed generating device and the motor are started, and in order to ensure the accuracy of simulation demonstration, the angles of the elevator and the rudder are adjusted before the wind speed generating device and the center line of the propeller rotating shaft are adjusted to be non-parallel and collinear, so that the interference moment generated by the slip flow is eliminated. And then moving the position of the wind speed generating device to enable the wind speed generating device to be not parallel to the central line of the rotating shaft of the propeller, releasing smoke, and observing the pitching and directional moment changes of the force measuring balance to simulate the generation and influence of the oblique blowing of the airflow.

Finally, it should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and not intended to limit the present invention, and although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications and equivalents can be made in the technical solutions described in the foregoing embodiments, or some technical features of the present invention may be substituted. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The utility model provides a piston screw side effect demonstration teaching aid which characterized in that includes: aircraft model (2), motor (3), elevator (4), rudder (5), dynamometry balance (6), biax revolving stage (7), support (8), wind speed generating device (9), smog (10) of screw (1) are equipped with, screw (1) is connected with motor (3), and the motor is fixed in aircraft model (2), elevator (4) are connected with the horizontal stabilizer of aircraft model (2), and rudder (5) are connected with the perpendicular stabilizer of aircraft model (2), and dynamometry balance (6) are connected with aircraft model (2), biax revolving stage (7), and biax revolving stage (7) are connected with support (8), and screw (1 the place ahead is arranged in wind speed generating device (9), and smog (10) are placed between wind speed generating device (9) and screw (1).

2. A piston propeller side effect demonstration teaching aid as claimed in claim 1, characterised in that the motor (3) is adjustable in speed.

3. A piston propeller side effect demonstration teaching aid as claimed in claim 1, characterised in that the fuselage of the model airplane (2) is hollow.

4. A piston propeller side effect demonstration teaching aid according to claim 2 or 3, characterised in that the motor (3) is placed inside the model airplane (2).

5. A piston propeller side effect demonstration teaching aid as claimed in claim 1, characterised in that the elevators (4) are angularly adjustable.

6. A piston propeller side effect demonstration teaching aid as claimed in claim 1, characterised in that the rudder (5) is angularly adjustable.

7. A piston propeller side effect demonstration teaching aid according to claim 1, characterised in that the load cell balance (6) is a device for measuring forces and moments.

8. A piston propeller side effect demonstration teaching aid according to claim 1 or 7, characterized in that the two-axis turntable (7) is provided with locking means.

9. A piston propeller side effect demonstration teaching aid as claimed in claim 1, characterised in that the wind speed generating device (9) is an adjustable speed axial or centrifugal fan.

10. A piston propeller side effect demonstration teaching aid according to claim 1 or 9, characterised in that the smoke (10) is coloured.

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