A test device for aerodynamic characteristics of a single rotor system with pull-torque decoupling

Abstract

The present invention discloses a pull-torque decoupled single-rotor system aerodynamic characteristic testing device, which belongs to the field of aerodynamic characteristic testing of single-rotor Mars helicopters, and comprises a torque measurement module and a thrust measurement module. In the torque testing module, the rotation of a motor rotor drives the rotor to rotate and generate torque, and at the same time, the motor stator generates a torque equal to the above torque in magnitude and opposite in direction, and the torque is transmitted to the torque sensor through the lower stepped shaft; in the thrust testing module, the thrust generated by the rotation of the rotor is transmitted to three force sensors through the motor, bearings, support tubes, and upper plates of force sensors, thereby solving the problem that existing aerodynamic characteristic testing devices are difficult to cope with the small thrust and low torque of the Mars helicopter rotor when hovering, resulting in excessive errors and low precision.

Description

Technical Field

[0001] The invention relates to the technical field of aerodynamic characteristic testing of a single-rotor Mars helicopter, and in particular to an aerodynamic characteristic testing device for a single-rotor system with a tension-torque decoupling. Background Art

[0002] The atmosphere of Mars is thin, with a density of less than 1% of the Earth, but this thin atmosphere makes the existence of the Mars helicopter possible. There are many ways for humans to explore Mars, and the most commonly used is the Mars rover. However, if the Mars rover and the Mars helicopter cooperate to explore Mars, then better results can be achieved. The Mars helicopter can explore a wider area and guide the Mars rover's direction to avoid obstacles. Mars has the characteristics of low Reynolds number and high Mach number, which poses a huge challenge to the design of the Mars drone.

[0003] The existing solution with patent number "CN207133000U" is used to solve the problem of measuring the torque and tension of the propeller-motor to facilitate the study of the dynamic characteristics of the propeller-motor system and ensure the propeller-motor screening and matching work. The environment used is the earth's atmosphere, which cannot meet the overall aerodynamic performance test of the Mars helicopter. For the Mars helicopter rotor, the torque and thrust test have large errors and low accuracy, and cannot accurately test the stress condition of the fuselage of the Mars helicopter when the propeller is rotated by electric drive, which makes it difficult to meet the aerodynamic performance test of the Mars helicopter rotor. Summary of the invention

[0004] In order to solve the deficiencies mentioned in the above background technology, the purpose of the present invention is to provide a thrust-torque decoupled single-rotor system aerodynamic characteristics test device, which solves the shortcomings of large error and low precision of existing ground aerodynamic characteristics test devices, and provides a thrust-torque decoupled single-rotor Mars helicopter aerodynamic characteristics test device with high precision and small error, which can test the thrust generated in both upward and downward situations of the rotor, and a method for testing the torque and thrust thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] The aerodynamic characteristics test device of the tension torque decoupling single rotor system of the present invention comprises a blade, a propeller clamp, a propeller clamp-motor connection flange, a motor, a sleeve, a bearing, a stepped shaft, an upper clamping ring of a torque sensor, a torque sensor, a lower clamping ring of a torque sensor, a support tube, a support tube mounting plate, a tension sensor, a mounting base plate, and a base;

[0007] The blades are fixed to the blade clamps and rotate around the center of rotation to generate thrust and torque;

[0008] The torque sensor measures the torque generated when the blades rotate;

[0009] The thrust sensor measures the thrust generated by the blades as they rotate.

[0010] The torque testing method of the aerodynamic characteristics testing device of the pull-torque decoupling single-rotor system of the present invention has the following specific process:

[0011] Step 1: The motor rotor drives the rotor to rotate at high speed, generating clockwise torque and counterclockwise reverse torque on the motor stator;

[0012] Step 2: The torque generated in step 1 passes through the stepped shaft and the clamping ring on the upper end of the torque sensor in sequence, causing a slight rotation of the shaft on the torque sensor;

[0013] Step 3: The angle between the upper shaft and the lower shaft of the torque sensor changes;

[0014] Step 4: The angle change generated in step 3 causes the strain gauge in the torque sensor to deform;

[0015] Step 5: The deformation of the strain gauge in step 4 causes the resistance of the strain gauge to change, so that the torque value is measured through the generated analog quantity;

[0016] The present invention can solve the problem that the existing rotor aerodynamic test device is only designed for Earth rotors, has large errors and low precision for Mars helicopter rotor startup tests, and can only test thrust in one direction. The pull-torque decoupled single rotor system aerodynamic characteristic test device described in the present invention is installed in a low-pressure simulated Mars environment in a large vacuum tank. When the rotor rotates, the torque sensor can measure the torques in two opposite directions generated by the forward and reverse rotation of the rotor, and the tension sensor can measure the thrusts in two directions generated by the rotor respectively. The aerodynamic characteristic test device can evaluate important indicators such as the rotor's airfoil structure, blade structure, and blade plane shape, and has a high scope of application and flexibility.

[0017] Beneficial effects of the present invention:

[0018] The present invention ensures the accuracy of torque measurement by installing a thrust ball bearing between the support tube and the torque sensor. The thrust ball bearing offsets most of the gravity, thereby solving the problem that the existing aerodynamic characteristics testing device is difficult to cope with the small thrust and low torque of the Mars helicopter rotor when hovering, resulting in excessive errors and low accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a schematic diagram of the installation position of the motor to the rotor part of the present invention;

[0022] Figure 3 is a schematic cross-sectional view of the torque sensor and surrounding parts of the present invention;

[0023] Figure 4 It is a schematic diagram of the installation positions of the upper clamping ring of the upper torque sensor, the torque sensor, and the lower clamping ring of the torque sensor of the present invention;

[0024] Figure 5 It is a schematic diagram of the installation position of the tension sensor of the present invention;

[0025] The reference numerals are as follows:

[0026] 1-blade, 2-propeller clamp, 3-propeller clamp-motor connecting flange, 4-motor, 5-sleeve, 6-bearing, 7-step shaft, 8-torque sensor upper clamping ring, 9-torque sensor, 10-torque sensor lower clamping ring, 11-support tube, 12-support tube mounting plate, 13-tension sensor, 14-mounting base plate, 15-base. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Embodiment 1: Figure 1-5 As shown, a test device includes a propeller clamp 2 and a motor 4, characterized in that: the propeller clamp 2 is installed on the motor 4 through a propeller clamp-motor connection flange 3, the motor 4 is fixedly installed on the upper end of the stepped shaft 7, a torque sensor 9 is fixedly installed on the lower end of the stepped shaft 7, and a tension sensor 13 is fixedly installed on the lower end of the torque sensor 9;

[0029] During the test, when the motor 4 rotates, the propeller clamp 2 is driven to rotate through the propeller clamp-motor connection flange 3. The propeller blades 1 are installed on both sides of the propeller clamp 2, and the propeller blades 1 are fixed by bolts. With such a design, the blades can be quickly replaced, and the high Reynolds number airfoil, low Reynolds number airfoil structure, number of blades, and geometric shape of the single rotor system can be evaluated in a convenient and fast manner according to various rotor index requirements.

[0030] When the blade 1 rotates, the rotor of the motor 4 rotates to drive the blade 1 to rotate and generate torque. At the same time, the stator of the motor 4 generates a torque equal to the torque and opposite to the direction. The torque is transmitted to the torque sensor 9 through the lower stepped shaft 7. The thrust generated by the rotation of the blade 1 is transmitted to the three tension sensors 13 through the motor 4, the bearing 6, the support tube 11, and the upper plate of the force sensor. The tension and stability of the helicopter fuselage when the blade 1 rotates are determined by comparing the differences in the test values ​​of multiple tension sensors 13. The fixed connection can ensure that the torque and thrust generated by the rotor when rotating are completely transmitted to the torque sensor 9 and the tension sensor 13.

[0031] In some disclosures, the upper end of the stepped shaft 7 is positioned by a boss and connected to the motor 4 by screws, and the lower end is positioned by a boss and connected to the clamping ring 8 at the upper end of the torque sensor by screws; such a design can ensure the coaxiality of the torque sensor 8 and the motor main shaft through the stepped shaft 7 to ensure the test accuracy.

[0032] In some disclosures, the upper and lower shafts of the torque sensor 9 are respectively installed with an upper clamping ring 8 of the torque sensor and a lower clamping ring 10 of the torque sensor, which are respectively connected to the stepped shaft 7 and the tension sensor 13 by bolts; further, the upper clamping ring 8 of the torque sensor and the lower clamping ring 10 of the torque sensor are fastened by bolts to clamp the side gaps; such a design can quickly complete the installation, disassembly and replacement of the torque sensor 9 through the upper clamping ring 8 of the torque sensor and the lower clamping ring 10 of the torque sensor, and perform later maintenance and measurement and correction.

[0033] In some disclosures, a sleeve 5 is provided on the outside of the stepped shaft 7, and the sleeve 5 is installed on the support tube 11; in this way, the motor can be protected by the sleeve 5 to avoid collision during the motor operation and thus cause equipment failure.

[0034] In some disclosures, the torque sensor 9 has a lower end clamping ring 10 installed on the lower end shaft of the torque sensor, and a support tube mounting plate 12 is installed below the lower end clamping ring 10 of the torque sensor. Three tension sensors 13 are evenly distributed in a circle and installed below the support tube mounting plate 12, and the lower end of the tension sensor 13 is installed on a mounting base plate 14; the mounting base plate 14 is fixedly installed on a base 15, so that the tension sensor 13 can be fixedly installed on the mounting base plate 14 to simulate the stress conditions of the helicopter and the motor mounting point when the blade 1 rotates, so as to test the stress conditions of the fuselage of the Mars helicopter when the propeller is rotated by electric drive, so as to avoid simply testing the stress conditions of the motor and causing inaccurate calculation of the fuselage stress conditions due to the different Martian environment.

[0035] In some disclosures, a support cylinder 11 is installed on the support cylinder mounting plate 12, and a bearing 6 is provided between the support cylinder 11 and the stepped shaft 7; further, the bearing 6 adopts a thrust ball bearing. Through such a design, the thrust ball bearing can offset most of the gravity and ensure the accuracy of the test results of the tension sensor 13 and the torque sensor 9.

[0036] The support tube mounting plate 12 and the support tube 11 are supported and fixed in cooperation with the bearing 6 to prevent the tension sensor 13 and the static torque sensor 9 from being subjected to tension and torque at the same time, which would interfere with the test accuracy. At the same time, the static torque sensor cannot give a torque value in real time.

[0037] Embodiment 2: Figure 1-5 As shown, a tension-torque decoupled single-rotor system aerodynamic characteristic testing device includes: a blade 1, a propeller clamp 2, a propeller clamp-motor connecting flange 3, a motor 4, a sleeve 5, a bearing 6, a stepped shaft 7, a torque sensor upper end clamping ring 8, a torque sensor 9, a torque sensor lower end clamping ring 10, a support tube 11, a support tube mounting plate 12, a tension sensor 13, a mounting base plate 14, and a base 15; the sleeve 5 is connected to the support tube 11 by bolts to shield the rotating motor 4.

[0038] There are two blades 1, which are connected to the two sides of the propeller clamp 2 by bolt connection; the propeller clamp 2 is positioned with the propeller clamp-motor connection flange through a stop to ensure coaxiality during rotation, and is connected by bolts; the propeller clamp-motor connection flange 3 is positioned with the motor 4 through a stop to ensure coaxiality during rotation, and is connected by screws; this embodiment can ensure that the torque and thrust generated by the rotor during rotation are completely transmitted to the torque sensor and the tension sensor.

[0039] The support tube mounting plate 12 is provided with a support tube 11 positioning stop and a torque sensor lower end clamping ring 10 mounting seat; first, the torque sensor lower end clamping ring 10 is connected to the support tube mounting plate 12 by screws, and then the lower end of the torque sensor 9 is inserted into the torque sensor lower end clamping ring 10, and the two bolts on the side of the torque sensor lower end clamping ring 10 are tightened to clamp the torque sensor 9.

[0040] Install the support tube 11 on the support tube mounting plate 12 by bolts, then embed the bearing 6 into the upper section of the support tube 11, connect the stepped shaft 7 and the upper clamping ring 8 of the torque sensor by bolts, then embed the stepped shaft 7 and the upper clamping ring 8 of the torque sensor into the inner ring of the bearing from above, and tighten the two bolts on the side of the upper clamping ring 8 of the torque sensor to clamp the upper shaft of the torque sensor. At this time, a small rotation difference can be generated between the upper shaft and the lower shaft of the torque sensor to measure the torque generated when the rotor rotates.

[0041] In some disclosures, the mounting base plate 14 is first installed on the base 15 by bolts. There are three tension sensors 13, which are evenly distributed and installed on the mounting base plate 14 by screw connection. The support tube mounting plate 12 is connected by screws above the tension sensor 13. In this way, it can be ensured that the thrust generated by the rotation of the rotor is completely measured by the tension sensor 13; the present disclosure has designed limiting measures for the upper and lower parts of the bearings, motors, tension sensors, and torque sensors to ensure that the upward and downward thrusts generated by the rotor during the experiment will not affect the structure of the present invention. The present invention can perform high-precision measurements of the clockwise and counterclockwise torques generated when the rotor rotates in a low-pressure environment, and can accurately measure the thrusts in the upward and downward directions generated by the rotor while ensuring the structural strength.

[0042] Embodiment 3: A method for testing the aerodynamic performance of a rotor, wherein the method places the device described in Embodiment 1 or 2 in a large vacuum tank for testing, thereby simulating the stress conditions of the helicopter body in the Martian atmosphere and providing real data for the Martian helicopter.

[0043] Furthermore, the air density in the large vacuum tank is 0.00129 kg / m3;

[0044] Furthermore, the air pressure in the large vacuum tank is 1Pa, the wingspan is 0.1m, and the rotor speed is 100rpm.

[0045] Embodiment 4: A method for testing the aerodynamic performance of a rotor, wherein the method places the device described in Embodiment 1 or 2 in a large vacuum tank for testing, thereby simulating the stress conditions of a helicopter body in the Martian atmosphere and providing real data for a Martian helicopter.

[0046] Furthermore, the air density in the large vacuum tank is 0.0129 kg / m3;

[0047] Furthermore, the air pressure in the large vacuum tank is 104Pa, the wingspan is 1.4m, and the rotor speed is 4000rpm.

[0048] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A device for measuring aerodynamic characteristics of a single-rotor system with a pull-torque decoupling, comprising a propeller clamp (2) and a motor (4), characterized in that: The propeller clamp (2) is mounted on the motor (4) via a propeller clamp-motor connection flange (3); the motor (4) is fixedly mounted on the upper end of the stepped shaft (7); a torque sensor (9) is fixedly mounted on the lower end of the stepped shaft (7); and a tension sensor (13) is fixedly mounted on the lower end of the torque sensor (9); The lower end shaft of the torque sensor (9) is equipped with a lower end clamping ring (10) of the torque sensor, a support tube mounting plate (12) is mounted below the lower end clamping ring (10) of the torque sensor, a tension sensor (13) is mounted below the support tube mounting plate (12), and the lower end of the tension sensor (13) is mounted on a mounting base plate (14); Three tension sensors (13) evenly distributed in a circle are installed below the support tube mounting plate (12); A support cylinder (11) is installed on the support cylinder mounting plate (12), and a bearing (6) is provided between the support cylinder (11) and the stepped shaft (7).

2. The device for measuring aerodynamic characteristics of a single-rotor system with a pull-torque decoupling according to claim 1, characterized in that: The upper end of the stepped shaft (7) is positioned by a boss and connected to the motor (4) by screws, and the lower end is positioned by a boss and connected to the upper clamping ring (8) of the torque sensor by screws.

3. The device for measuring aerodynamic characteristics of a single-rotor system with a pull-torque decoupling according to claim 1, characterized in that: The upper and lower shafts of the torque sensor (9) are respectively provided with an upper clamping ring (8) of the torque sensor and a lower clamping ring (10) of the torque sensor. The upper clamping ring (8) of the torque sensor and the lower clamping ring (10) of the torque sensor are respectively connected to the stepped shaft (7) and the tension sensor (13) via bolts. The upper clamping ring (8) of the torque sensor and the lower clamping ring (10) of the torque sensor are fastened by clamping the gaps on the sides via bolts.

4. The device for measuring aerodynamic characteristics of a single-rotor system with a pull-torque decoupling according to claim 1, characterized in that: A sleeve (5) is provided on the outside of the stepped shaft (7), and the sleeve (5) is installed on the support tube (11).

5. The device for measuring aerodynamic characteristics of a single-rotor system with a pull-torque decoupling according to claim 1, characterized in that: The blades (1) are installed on both sides of the blade clamp (2), and the blades (1) are fixed by bolts.

6. A method for testing rotor aerodynamic performance, characterized in that: The method is carried out by placing the aerodynamic characteristics measuring device of a pull-torque decoupled single-rotor system as described in claim 1 in a large vacuum tank for testing.

7. A rotor aerodynamic performance testing method according to claim 6, characterized in that: The air pressure in the large vacuum tank is 1-104Pa.

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