CN115371934A - Vibration and collision prevention position control method for wind tunnel test - Google Patents

Abstract

The invention provides a vibration and collision prevention position control method for a wind tunnel test, which comprises the steps of respectively arranging an accelerometer and a laser ranging sensor linear array on the surfaces of a fan nacelle simulation device and a wing model, obtaining the parameters and control input of a PID (proportion integration differentiation) controller for controlling the movement of a slide rail, controlling a movement servo motor by the PID controller, and driving the wing model to move, so that the surface of the wing model and a fan nacelle hanging rack supporting rod are prevented from violently colliding due to vibration, and the attachment in the elastic range of a silica gel layer is kept.

Description

Vibration and collision prevention position control method for wind tunnel test

Technical Field

The invention belongs to the technical field of wind tunnel tests, and particularly relates to a vibration and collision prevention position control method for a wind tunnel test.

Background

The engine body mounting effect noise refers to noise generated by mutual interference between the engine body and the engine. The wind tunnel test is an important means for researching the noise problem of the installation effect of the machine body/the fan. Because the aerodynamic noise of the turbofan aircraft is obviously influenced by the interference of the airframe and the engine, a test method for measuring and controlling the relative position of the model and the fan nacelle in real time in a wind tunnel flow field needs to be established, and necessary test conditions are provided for the airframe installation effect noise type wind tunnel test.

Disclosure of Invention

The invention aims to provide a vibration and collision prevention position control method for a wind tunnel test, which measures the relative distance between the surface of a wing model and a fan nacelle model hanging rack in real time in the wind tunnel test process, prevents the surface of the wing model and the fan nacelle model hanging rack from being violently extruded and collided due to vibration, and keeps the attachment within the elastic range of a silica gel layer.

In order to realize the purpose, the technical scheme adopted by the invention is as follows: a vibration and collision prevention position control method for a wind tunnel test comprises the following steps:

step 1, a wing model is vertically arranged on a four-degree-of-freedom platform, the four-degree-of-freedom platform is arranged on a slide rail, the four-degree-of-freedom platform is driven by a moving servo motor to move on the slide rail, and a hydraulic support structure is used for supporting a fan nacelle model and adjusting the attack angle change of the fan nacelle model;

step 2, arranging accelerometers in a shell and a shaft sleeve of the fan nacelle model, carrying out a blowing test without installing an airfoil model, and measuring to obtain the amplitude of the fan nacelle model in a flow field;

step 3, building a control system, obtaining an initial value of parameter setting of a PID controller of a servo motor for controlling the wing model to move on the slide rail according to the amplitude measured by the accelerometer, and building the PID controller after the parameter setting; the control system comprises an industrial personal computer, a PLC and a frequency converter, wherein the industrial personal computer, the PLC and the frequency converter are sequentially in electrical signal connection, and the frequency converter is connected with the mobile servo motor;

step 4, arranging five laser ranging sensors in parallel on the surface of the wing model to form a laser ranging sensor linear array, ensuring that at least three sensors in the linear array can measure the distance to the outer wall surface of the fan nacelle model hanger support rod, equivalently obtaining the coordinates of three points on the circumference of the cross section of the support rod, taking the position of any laser ranging sensor as the origin of coordinates, taking the connecting line of the five sensors as the Y axis, taking the laser beam emitted by the laser ranging sensor as the X axis, establishing a plane rectangular coordinate system, and further obtaining the minimum distance from the surface of the wing model to the outer wall surface of the fan nacelle model hanger support rod;

step 5, taking the minimum distance obtained after the processing as feedback, making a difference with a target value, and taking the difference as the control input quantity of the PID controller obtained in the step 3;

and 6, controlling a moving servo motor by using a PID controller to drive the wing model to move, repeating the steps 3-5, and performing real-time closed-loop control on the relative positions of the wing model and the fan nacelle model hanging rack supporting rod to ensure that the wing model and the fan nacelle model can be kept in fit in the test process and severe extrusion collision caused by the jitter of airflow in a wind tunnel flow field can be avoided.

The invention has the advantages and beneficial effects that: the invention provides a vibration-proof collision position control method for a wind tunnel test, which can prevent the surface of a wing model from violently colliding with a fan nacelle hanging frame due to vibration and keep the attachment within the elastic range of a silica gel layer.

Description of the drawings:

FIG. 1 is a flow chart of a control method for vibration-proof collision position in wind tunnel test.

FIG. 2 is a schematic view of a machine body/fan installation effect noise wind tunnel test device.

FIG. 3 is a schematic diagram of arrangement of linear arrays of laser ranging sensors on the surface of an airfoil model.

FIG. 4 is a cross-sectional view of the relative position relationship between the linear array and the support rod of the laser ranging sensor.

FIG. 5 is a schematic diagram of a servo motor PID position control.

The system comprises a machine body model 1, a fan nacelle simulator 2, a hydraulic support 3, a four-degree-of-freedom platform 4, a wind tunnel nozzle 5, a wind tunnel collector 6, a fan nacelle simulator supporting rod 7 and a laser ranging sensor 8.

The specific implementation mode is as follows:

in order to make the purpose and technical solutions of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. The described embodiments are some, but not all embodiments of the present application. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and are not to be construed as limiting the application. All other embodiments obtained by a person of ordinary skill in the art without any inventive work based on the embodiments in the present application belong to the protection scope of the present application, and the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Example 1

As shown in fig. 1, a method for controlling an anti-vibration collision position in a wind tunnel test comprises the following steps;

step 1, building a support structure, wherein the support structure is respectively used for supporting a wing model and a fan nacelle simulation device; as shown in fig. 2, the wing model is vertically installed on a four-degree-of-freedom platform, the four-degree-of-freedom platform is installed on a slide rail, the four-degree-of-freedom platform is driven by a mobile servo motor to move on the slide rail, and the four-degree-of-freedom platform structure comprises: ball, straight line unit, carousel. The freedom degree of the wing model is adjusted through the ball screw, the linear unit and the turntable together to realize change. The hydraulic support structure is used for supporting and adjusting the fan nacelle model and comprises a fan nacelle model hanging rack supporting rod, a connecting lever structure, a lifting upright post, a lifting guide rail, a follow-up cable and a well.

Step 2, arranging accelerometers in a shell and a shaft sleeve of the fan nacelle model, firstly carrying out a blowing test without installing an airfoil model, and measuring to obtain the amplitude of the fan nacelle model in a flow field;

step 3, building a control system, obtaining an initial value of parameter setting of a PID controller of a servo motor for controlling the wing model to move on the slide rail according to the amplitude measured by the accelerometer, and building the PID controller after the parameter setting; the control system comprises an industrial personal computer, a PLC and a frequency converter, wherein the industrial personal computer, the PLC and the frequency converter are sequentially in electrical signal connection, and the frequency converter is connected with the mobile servo motor;

step 4, as shown in fig. 3-4, arranging five laser ranging sensors in parallel on the surface of the wing model to form a laser ranging sensor linear array, taking the position of a third laser ranging sensor as a coordinate origin, connecting lines of the five sensors as Y axes, and laser beams emitted by the laser ranging sensors as X axes, establishing a planar rectangular coordinate system, wherein the vibration amplitude of a strut in a wind tunnel test is not more than 6cm at most, according to geometric analysis, under the most extreme condition, at least 3 sensors in the linear array can be ensured to be capable of measuring the distance to the surface of the strut, which is equivalent to obtaining the coordinates of three points on the circumference of the cross section (diameter of 180 mm) of the strut, so as to obtain the minimum distance from the surface of the wing model to the outer wall surface of the strut;

step 5, as shown in fig. 5, taking the minimum distance obtained after the processing as feedback, making a difference with a target value, and taking the difference as the control input quantity of the PID controller obtained in the step 3;

and 6, controlling a moving servo motor by using a PID controller to drive the wing model to move, repeating the steps 3-5, and performing real-time closed-loop control on the relative positions of the wing model and the fan nacelle model hanging rack supporting rod to ensure that the wing model and the fan nacelle model can be kept in fit in the test process and severe extrusion collision caused by the jitter of airflow in a wind tunnel flow field can be avoided.

Example 2

Before testing, the ground debugging of the fan nacelle simulator is carried out, including fan dynamic balance testing, motor transmission testing, and the installation arrangement and testing of all sensors. During testing, the center of the fan nacelle simulation device is over against the center of the wind tunnel nozzle, and the corresponding height of the body model support is adjusted. Firstly, carrying out a blowing test without installing an airfoil model, obtaining the amplitude of a nacelle simulation device through an accelerometer, further obtaining an initial value of PID parameter setting, then carrying out parameter setting, and establishing a PID controller. After the model is installed in place, the installation condition of the model is checked, the running condition of the test device is checked, the model is ensured to be installed accurately, and the test device can run normally. After the states of the test equipment and the model are determined, a wind tunnel test can be developed, and the linear array measurement data of the laser ranging sensor is collected in real time to obtain the distance between the surface of the wing model and the nacelle hanger. The wind tunnel wind speed and the fan rotating speed are gradually increased from low to high, after safety is determined, a target value is input, the servo motor is controlled by the PID controller to drive the wing model, the relative position of the wing model and the nacelle hanging frame is controlled in a closed-loop mode in real time, and the test requirement of a wind tunnel test of the installation effect noise of the engine body/the fan is met.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (1)

1. A vibration and collision prevention position control method for a wind tunnel test is characterized by comprising the following steps:

step 1, a wing model is vertically arranged on a four-degree-of-freedom platform, the four-degree-of-freedom platform is arranged on a slide rail, the four-degree-of-freedom platform is driven by a moving servo motor to move on the slide rail, and a hydraulic support structure is used for supporting a fan nacelle model and adjusting the attack angle change of the fan nacelle model;

step 2, arranging accelerometers in a shell and a shaft sleeve of the fan nacelle model, carrying out a blowing test without installing an airfoil model, and measuring to obtain the amplitude of the fan nacelle model in a flow field;

step 3, building a control system, obtaining an initial value of parameter setting of a PID controller of a servo motor for controlling the wing model to move on the slide rail according to the amplitude measured by the accelerometer, and building the PID controller after the parameter setting; the control system comprises an industrial personal computer, a PLC and a frequency converter, wherein the industrial personal computer, the PLC and the frequency converter are sequentially in electrical signal connection, and the frequency converter is connected with the mobile servo motor;

step 4, arranging five laser ranging sensors in parallel on the surface of the wing model to form a laser ranging sensor linear array, ensuring that at least three sensors in the linear array can measure the distance to the outer wall surface of the fan nacelle model hanger support rod, equivalently obtaining the coordinates of three points on the circumference of the cross section of the support rod, taking the position of any laser ranging sensor as the origin of coordinates, taking the connecting line of the five sensors as the Y axis, taking the laser beam emitted by the laser ranging sensor as the X axis, establishing a plane rectangular coordinate system, and further obtaining the minimum distance from the surface of the wing model to the outer wall surface of the fan nacelle model hanger support rod;

step 5, taking the minimum distance obtained after the processing as feedback, making a difference with a target value, and taking the difference as the control input quantity of the PID controller obtained in the step 3;

and 6, controlling a moving servo motor by using a PID controller to drive the wing model to move, repeating the steps 3-5, and performing real-time closed-loop control on the relative positions of the wing model and the fan nacelle model hanging rack supporting rod to ensure that the wing model and the fan nacelle model can be kept in fit in the test process and severe extrusion collision caused by the jitter of airflow in a wind tunnel flow field can be avoided.

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