CN115901170A

CN115901170A - Vibration inertia actuation suppression device for wind tunnel model

Info

Publication number: CN115901170A
Application number: CN202211603388.5A
Authority: CN
Inventors: 刘巍; 孙晨晋; 周孟德; 张新雨; 任宇航; 王琴琴; 张沛东
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2021-12-14
Filing date: 2022-12-13
Publication date: 2023-04-04
Also published as: CN114323549A

Abstract

The invention belongs to the field of active control of vibration of a wind tunnel model of an aircraft, and provides a vibration inertia actuation suppression device of the wind tunnel model. The device comprises a shell base, an end cover, a bearing, a main shaft, a positioning nut, a positioning shaft sleeve, an inertial mass block, a coupler, a motor part, an end cover fastening screw, a motor mounting screw, a motor connecting key, a main shaft connecting key and a mass block connecting key fastener, wherein the end cover fastening screw, the motor mounting screw, the motor connecting key, the main shaft connecting key and the mass block connecting key fastener are coaxially mounted in a tail cavity of an aircraft model, and the inertial mass block is driven to perform circular motion to provide inertial vibration suppression force, so that the control of the pitching and yawing two-degree-of-freedom compound vibration of the aircraft wind tunnel model is realized. The device has compact structure and simple and convenient control, is arranged in the cavity in the model to avoid additional influence on the pneumatic appearance of the model, and has great application potential.

Description

Vibration inertia actuation suppression device for wind tunnel model

Technical Field

The invention relates to the field of active control of wind tunnel model vibration of aircrafts, in particular to a wind tunnel model vibration inertia actuation suppression device which has the function of suppressing wind tunnel model pitching and yawing composite vibration.

Background

The wind tunnel model test is an important way for researching the aerodynamic characteristics of the aircraft and reducing the development cost and risk of the aircraft. The aircraft model is most often installed in the wind tunnel in a tail support and belly support mode, is similar to a cantilever in structure, and has the characteristics of weak rigidity and low damping. In addition, due to the influence of the pulsating force of the airflow in the test section, the model is easy to generate irregular vibration, the aerodynamic force measurement precision is seriously influenced, even the structure of the model is damaged, and the vibration of the model must be actively inhibited.

At present, an active vibration suppression device based on piezoelectric ceramics becomes the mainstream, the piezoelectric ceramics is used as a driving element, the vibration suppression device is arranged at the tail end or the middle section of a support rod, control voltage is applied to enable the device to output vibration suppression force, and the active vibration suppression device is widely applied to a model tail support mode. However, for a large-size wind tunnel model under a low-speed test condition, an abdominal supporting mode is generally adopted, the vibration suppression device is difficult to arrange due to the fact that the supporting rod structure is special, and the control complexity is greatly increased due to the complex vibration mode.

The vibration control means based on the inertia actuation principle has the advantages of simple structure and low control cost of the vibration suppression device, and is widely applied to the fields of vibration control of running loads of ships, wind load vibration control of bridges and the like. In the field of ship vibration control, electric vibration absorbers based on the inertial actuation principle are commercialized, and the principle is that centrifugal control force is output by controlling a rotary inertial actuator to suppress the vibration of a ship body low-frequency structure caused by a ship main engine and a propeller. In the field of bridge vibration control, a dual-rotor damper is adopted to provide periodic variation vibration suppression force and suppress periodic vibration of a bridge body caused by wind load.

However, the electromagnetic inertial actuator is rarely applied to the field of vibration control of wind tunnel models, and a paper "experimental research on an active vibration reduction system of a transonic wind tunnel force measurement model" published by Chenweidong et al of the university of aerospace in Nanjing in 2007 develops an electromagnetic inertial actuator, builds a set of vibration active control system, takes vibration acceleration signals as feedback, and drives the actuator to output pitching direction inertial force through control decision, and the vibration suppression effect reaches more than 70%. The device utilizes the inner space of the model, two electromagnetic inertia actuators are arranged in parallel in the front cavity in the model, but the output force is in the pitching direction, so the device only has the capability of restraining the vibration in the pitching unidirectional direction. Meanwhile, the device is large in size, limited in output force and limited in vibration suppression effect.

Disclosure of Invention

The invention mainly solves the technical problem of overcoming the defects of the prior art, provides the vibration inertia actuation restraining device of the wind tunnel model, and realizes the compound vibration control of the pitching and yawing double-freedom degree of the wind tunnel model of the aircraft. The device is internally provided with an inertial mass block 8 driven by a motor, and the inertial mass block is controlled to output an inertial force opposite to the resultant force of the pitching and yawing direction vibration by utilizing the characteristic that the circular motion provides an inertial centrifugal force, so that the compound vibration of the pitching and yawing two degrees of freedom of the model is inhibited. The invention is arranged in the tail cavity in the model and is coaxial with the tail supporting rod of the model, and has the characteristics of compact structure, simple and convenient control and no influence on the pneumatic appearance of the model.

The technical scheme adopted by the invention is as follows:

a vibration inertia actuation suppression device for a wind tunnel model comprises a shell base 1, an end cover 2, an end cover set screw 3, a bearing 4, a main shaft 5, a pre-tightening nut 6, a positioning shaft sleeve 7, an inertia mass block 8, a coupling 9, a motor 10, a motor mounting screw 11 and a mass block connecting key 15, wherein the assembly connection is realized to realize motion and force transmission;

the shell base 1 is a cylinder with a bottom which protrudes outwards in the circumferential direction, the outer surface of the top end of the shell base is connected with the end cover 2 through an end cover set screw 3, and the inner surface of the bottom end of the shell base is connected with the motor 10 through a motor mounting screw 11; the top end of the shell base 1 is provided with a groove for mounting a bearing 4; the lower end of the main shaft 5 is connected with a motor 10 through a coupler 9, the coupler 9 transmits the output torque of the motor 10 to the main shaft 5 through a motor connecting key 13 and a main shaft connecting key 14, and then an inertia mass block 8 is driven to perform circular motion with the main shaft as the center through a mass block connecting key 15, and the generated centrifugal inertia force is reacted with the shell base 1; the upper end of the main shaft 5 penetrates through the shell base 1 and is connected with the bearing 4; the pre-tightening nut 6 and the positioning shaft sleeve 7 are sequentially fixedly sleeved on the main shaft 5; the inertial mass block 8 is in a T shape and performs circular motion by taking the main shaft 5 as a center, the inertial mass block is axially fixed on the main shaft 5 through a pretightening nut 6 and a positioning shaft sleeve 7, and the inertial mass block is circumferentially fixed through a mass block connecting key 15;

the outer shell base 1 bottom end edge convex department evenly arranges 6 mounting holes 12 for install whole device in the afterbody cavity of aircraft model 16, and dynamometry balance 17 is located the shell base 1 top end side, and this wind-tunnel model vibration inertia actuates restraining device 18 and dynamometry balance 17 coaxial arrangement in the afterbody cavity of aircraft model 16, realizes the compound vibration control to aircraft wind-tunnel model pitch, driftage two directions.

The coupling 9 is connected with the motor through a motor connecting key 13 and is connected with the spindle through a spindle connecting key 14.

The invention has the beneficial effects that: the invention designs a vibration inertia actuation suppression device for a wind tunnel model, which realizes effective active suppression of the pitching and yawing two-degree-of-freedom vibration of an airflow load excitation model. The motor drives the inertial mass block to do circular motion, centrifugal inertial force is generated to act on the model support rod system, and the direction of the centrifugal inertial force is controlled to be opposite to the direction of the resultant force of pitching and yawing two-degree-of-freedom vibration of the model in real time, so that the composite vibration of the model excited by airflow load is weakened, the damping of the model support system is increased, the stability of the model is ensured, and the accuracy of the measured data of the wind tunnel test is improved.

Drawings

FIG. 1 is an overall structure diagram of a vibration inertia motion suppression device for a wind tunnel model according to the present invention;

FIG. 2 is a front cross-sectional view of the device of the present invention;

FIG. 3 is a schematic diagram of the vibration suppression arrangement of the present invention;

FIG. 4 is a schematic view of the installation of the apparatus of the present invention;

fig. 5 is a graph of a vibration acceleration monitoring result of a hammering experiment of an aircraft model.

In the figure: 1-a shell base, 2-an end cover, 3-an end cover set screw, 4-a bearing, 5-a main shaft, 6-a pre-tightening nut, 7-a positioning shaft sleeve, 8-an inertia mass block, 9-a coupler, 10-a motor, 11-a motor mounting screw, 12-a mounting hole, 13-a motor connecting key, 14-a main shaft connecting key, 15-a mass block connecting key, 16-an aircraft model and 17-a force measuring balance.

Detailed Description

The following detailed description of the embodiments of the invention refers to the accompanying drawings.

FIG. 1 is a diagram of the whole structure of the vibration inertia motion suppression device of a wind tunnel model according to the present invention,

fig. 2 is a front sectional view thereof. According to actual test requirements, the motor 10 is a disk motor with low-speed and high-torque output characteristics.

In the specific implementation process, the end cover 2 and the disc motor 10 are respectively fastened and mounted on the shell base 1 by the end cover fastening screw 3 and the motor mounting screw 11, and the bearing 4 is mounted and positioned through the shaft shoulder and the end cover of the shell base 1. The coupling 9 is connected with the motor 10 through a motor connecting key 13 and is connected with the spindle 5 through a spindle connecting key 14. The inertial mass block 8 is axially fixed through the positioning shaft sleeve 7 and the pre-tightening nut 6, and is circumferentially fixed through the mass block connecting key 15. Through the steps, the active vibration suppression device is assembled.

Further, the vibration inertia motion suppression device is installed in a tail cavity of an aircraft model 16 through 6 installation holes 12 in a bolt connection mode and is coaxial with a force balance 17, and the installation schematic diagram of the device is shown in fig. 4.

FIG. 3 is a vibration suppression schematic diagram of the device of the present invention, wherein two acceleration sensors are respectively arranged in the pitch and yaw orthogonal vibration directions at the center of mass of the model during the specific implementation of the control, the vibration signals of two degrees of freedom of pitch and yaw are collected and input into a real-time controller to obtain the vibration force F in the pitch direction _f And yaw direction vibration force F _p . An X axis is established along the yaw vibration direction, a Y axis is established along the pitching vibration direction, and then the vibration resultant force F can be obtained _h Is inclined with respect to the positive direction of the X-axis by an angle theta. The control mode of the motor is position control, and the control target is the motor rotation angle theta _d The resultant direction angle theta is always retarded by 180 deg. compared to the vibration. The controller outputs a control signal after real-time resolving to drive the inertial mass block 8 to do circular motion and generate F _h Real-time opposing centrifugal inertial force F. The centrifugal inertia force always performs negative work on the structural vibration, and plays a role of additional damping to consume the structural kinetic energy, so that the pitching and yawing composite vibration of the wind tunnel model is reduced and inhibited, and meanwhile, the vibration amplitude attenuation condition of the model can be monitored in real time through an oscilloscope, and the vibration state of the model can be observed.

Fig. 5 is a diagram of a result of monitoring a vibration acceleration of a hammering experiment of an aircraft model, after a broadband load is applied, the model generates large-amplitude vibration at a natural frequency in a pitching vibration plane and a yawing vibration plane, the pitching vibration direction and the yawing vibration direction are vertical, a phase difference is fixed, and the combined vibration acceleration direction periodically changes along a circumferential radial direction. When the device is applied, the rotation angle of the motor is controlled in real time, so that the direction of the inertial centrifugal force is opposite to the direction of the combined vibration acceleration in real time and the change rule is consistent, and the reduction and the inhibition of the pitching and yawing composite vibration of the model can be realized.

The vibration inertia actuation suppression device for the wind tunnel model can effectively suppress model pitching and yawing two-degree-of-freedom composite vibration excited by airflow load in a wind tunnel test, and improve aerodynamic force measurement data precision. The device has compact structure and simple and convenient control, is arranged in the cavity in the model to avoid additional influence on the pneumatic appearance of the model, and has great application potential.

Claims

1. A wind tunnel model vibration inertia actuation suppression device is characterized by comprising a shell base (1), an end cover (2), an end cover set screw (3), a bearing (4), a main shaft (5), a pre-tightening nut (6), a positioning shaft sleeve (7), an inertia mass block (8), a coupling (9), a motor (10), a motor mounting screw (11) and a mass block connecting key (15);

the shell base (1) is a cylinder with a bottom which protrudes outwards in the circumferential direction, the outer surface of the top end of the shell base is connected with the end cover (2) through an end cover set screw (3), and the inner surface of the bottom end of the shell base is connected with the motor (10) through a motor mounting screw (11); the top end of the shell base (1) is provided with a groove for mounting the bearing (4); the lower end of the main shaft (5) is connected with a motor (10) through a coupler (9), and the upper end of the main shaft (5) penetrates through the shell base (1) to be connected with the bearing (4); the pre-tightening nut (6) and the positioning shaft sleeve (7) are sequentially fixedly sleeved on the main shaft (5); the inertial mass block (8) is in a T shape, performs circular motion by taking the main shaft (5) as a center, is axially fixed on the main shaft (5) through a pre-tightening nut (6) and a positioning shaft sleeve (7), and is circumferentially fixed through a mass block connecting key (15);

6 mounting holes (12) are uniformly arranged at the convex part of the edge of the bottom end of the shell base (1) for mounting; the force measuring balance (17) is positioned at the top end side of the shell base (1); the wind tunnel model vibration inertia actuation suppression device (18) and the force measuring balance (17) are coaxially arranged in a tail cavity of the aircraft model (16).