JPH1062297A - Fluid vibration testing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a test with eliminating the need for the disassemblying, replacing, reassemblying, etc., of a testing device even in the case when the test is performed with modifications in conditions such as weight, etc. SOLUTION: A structure 3 is vibrated in receiving ambient streams 2, and its displacement is inputted a controlling device 12 by a displacement meter 6. A load cell 11 measures a force exerted on the structure 3 to input to the controlling device 12. In the controlling device 12, at S1, an acceleration is obtained by twice differentiating the signal of the displacement meter 6, an inertial force is obtained from the weight of the structure, and a fluid force by the streams of the structure 3 is obtained by subtracting the force measured by the load cell 11. At S2, the coefficient data 14 of vibration characteristics inputted in advance is obtained, and vibration response from the fluid force are obtained to control a shaker 7 via a servo amplifier 13 so that the vibration response obtained in the calculation above may agree with the displacement measured by the displacement meter 6. Therefore, it is possible to perform a test with modifications in the weight, etc., of the structure 3 only by changing the coefficient data 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow vibration test apparatus for examining the characteristics of so-called flow vibration, in which a structure vibrates in response to a flow, and for example, measures the flow in various plants such as nuclear power plants, thermal power plants, and chemical plants. The test apparatus is applied to all structures that can be generally subjected to a flow and vibrate, such as a structure receiving a flow, a structure receiving a flow such as a building, a bridge, a steel tower, and the like.

[0002]

2. Description of the Related Art An example of a conventional experimental apparatus relating to flow vibration will be described with reference to the block diagram of FIG. In this experimental system, a structure 3 is arranged so as to be surrounded by a flow path wall 1 and receive a flow 2 around it, and the vibration of the structure 3 due to the flow 2 is examined. For this purpose, the structure 3 is supported by the flexible support rod 4 and fixed to the fixed end 5. The structure 3 vibrates due to the surrounding flow 2, and its movement is measured by various sensors such as a displacement gauge 6.

For example, when examining the vibration of a valve in a plant, the structure 3 corresponds to the valve, and the soft support rod 4 corresponds to the valve rod. In this experimental system, using a full-scale or reduced-scale model of a valve in a plant, a fluid is flowed to measure the vibration of the valve. Then, the relationship between the flow velocity and the magnitude of the vibration of the valve is examined, and the flow velocity, valve weight, valve rod rigidity, and the like in the plant design are set.

[0004] Another example of a conventional experimental system relating to flow vibration will be described with reference to the configuration diagram of FIG. The configuration and operation of the flow path wall 1, flow 2, structure 3, flexible support rod 4, fixed end 5, and displacement gauge 6 in this experimental system are the same as those in the system of FIG. This system is characterized in that the structure 3 is provided with a vibrator 7 in order to check the natural frequency and the damping ratio, which are the vibration characteristics of the structure 3 that vibrates in response to the flow 2.

Here, the vibrator 7 may be a vibrator directly attached to the structure 3, or may be a non-contact vibrator such as an electromagnet. For example, the structure 3 is vibrated by the vibrator 7 and the so-called sweep vibration is performed in which the vibration frequency at that time is gradually changed.
Is measured by the displacement meter 6. The natural frequency and the damping ratio, which are the vibration characteristics of the structure 3, can be obtained from the relationship between the excitation frequency and the vibration response of the structure 3.

A vibration test apparatus for a fluid device disclosed in Japanese Patent Application Laid-Open No. 55-62340 will be described with reference to FIG. The structure 35 includes a stand 36 fixed to a base 40.
The structure 35 is supplied with water from a supply pipe 38 and discharged from a discharge pipe 39 on the opposite side. This apparatus is an experimental apparatus for examining the flow vibration in which the structure 35 vibrates due to the flow 41 flowing inside. In this experimental apparatus, the structure 35 is vibrated by a vibrator 37 provided at one end of the structure 35 in order to examine the vibration characteristics of the structure 35. The natural frequency and the damping ratio, which are the vibration characteristics of the structure 35, can be obtained from the relationship between the excitation frequency and the vibration response of the structure 35.

[0007]

In the above-mentioned conventional flow vibration experiment system, when changing the weight of the structure or the rigidity or damping of the soft support rod, it is necessary to dismantle the experimental device and replace the structure. It takes time and effort. In particular, in an experimental apparatus for flow vibration caused by the flow of a fluid such as water which needs a seal, it is necessary to re-seal after disassembly, which requires a lot of labor and time.

Further, in an experimental apparatus for examining vibrations caused by a fluid such as steam or air at a high temperature and a high pressure, it is necessary to disassemble a heavy-weight pressure vessel and replace the structure, which requires a great deal of labor and time. I do.

For examining, for example, the vibration of a structure caused by the flow of water vapor, an experiment is usually performed with air that is easy to handle. In this case, the density of the air is about 1/30 that of water vapor. Therefore, the density of the structure must be reduced to about 1/30 in order to satisfy the similarity rule. However, about 1 / 30th of iron, which is the material of the actual structure,
It is almost impossible to experiment with materials with a density of.
Therefore, it is very difficult to set a structure so as to satisfy the similarity rule, for example, when a test is performed using a fluid different from an actual fluid.

Therefore, a first object of the present invention is to change the vibration characteristics such as the weight, rigidity, and damping of a structure only by changing the coefficient of the characteristic data of the control device. It is an object of the present invention to provide a flow vibration experiment apparatus that does not require dismantling, replacing a structure, reassembling, and the like, and can reduce labor and cost.

A second problem is that, in addition to the above-mentioned problems, a control device for realizing such a flow experiment device is also supplied with a displacement signal of a structure and an acceleration signal. An object of the present invention is to make it possible to accurately calculate and control the excitation force of the vibration characteristic data of a desired structure only by changing the data input.

A third object of the present invention is to provide a specific structure of the above-described control device and its vibrating means which can easily vibrate a structure using an actuator or the like.

A fourth object of the present invention is to provide a specific configuration of the above-described control device and its vibrating means, in which a fluid flow path is controlled to obtain a vibrating force.

[0014]

Accordingly, the present invention provides the following means (1) to (4) in order to solve the above first to fourth objects.

(1) a vibrator for vibrating a structure receiving a flow in a fluid flow path; a load meter for measuring a load applied to the structure; a displacement meter for measuring a vibration displacement of the structure; The signals of the load meter and the displacement meter are input, the fluid force due to the flow of the structure is obtained, and the fluid force and the previously input vibration characteristic data such as the weight, rigidity, damping, etc. of the virtual structure to be realized are obtained. A control device for calculating a vibration displacement of a virtual structure to be realized, and controlling a vibration of the vibrator so that the calculated vibration displacement matches a vibration displacement measured by the displacement meter. Flow vibration experiment equipment.

(2) vibrating means for vibrating a structure which receives a flow in a fluid flow path; an accelerometer for measuring acceleration of the structure; a displacement meter for measuring vibration displacement of the structure; Input the signals of the accelerometer and the displacement meter, find the vibration speed with the differentiator from the signal of the displacement meter, and input the weight, damping, and rigidity vibration characteristics data of the structure in advance and the virtual structure to be realized. Compare the vibration characteristic data, based on the difference between the two characteristic data, the input vibration displacement of the structure, the obtained vibration speed, the inertial force to be corrected from the input vibration acceleration, damping force, restoring force respectively Calculate,
A flow controller for controlling the vibrating means so as to obtain a sum of the calculated values and apply a vibrating force to the structure based on the signal.

(3) In the above (2), the vibrating means comprises an actuator such as a piezoelectric element, and the flow rate of the fluid is changed by the actuator to control the flow rate into the structure. A flow vibration experiment apparatus characterized by applying an exciting force to a plate.

(4) In the above (2), an electrorheological fluid is used as the fluid as the vibrating means, and electrodes are provided on both sides of the structure and the flow path wall. A flow vibration experiment device characterized by applying a vibration force to a structure.

In (1) of the present invention, the structure can be vibrated by a vibrator installed on the structure via, for example, a support rod or the like. This device measures the force applied to the structure, calculates the vibration displacement of the virtual structure that you want to achieve when receiving the force by the controller, and calculates the actual vibration displacement of the structure measured by the displacement meter. Then, the structure is vibrated by moving the exciter so as to have the calculated vibration displacement.

Further, in the above (1), the appearance of the structure vibrating when subjected to a certain force depends on the vibration characteristics of the virtual structure to be realized, such as the weight of the structure, the rigidity of the support rod, and the damping. This characteristic data is input to the control device in advance and stored. The controller calculates all the vibrations of the virtual structure that you want to realize from the forces applied to the structure, but the controller inputs the signals of the load meter and the displacement meter, and , And the shaker is controlled by the signal. The vibration characteristic of the virtual structure to be realized can be freely set as a coefficient in the control device.

Therefore, in the invention of the above (1), when changing the characteristics of the structure such as the weight of the structure, the rigidity of the support rod, and the damping, it is not necessary to dismantle the experimental apparatus and replace the structure. It can be easily handled by changing the coefficient in the control device. Further, even when an experiment is performed using a fluid different from the actual fluid, it is only necessary to adjust the coefficient in the control device for determining the characteristics of the virtual structure to be realized so as to satisfy the similarity rule.

In (2) of the present invention, as the vibration means for vibrating the structure, for example, an electromagnet can be used. In this device, the vibration displacement and vibration acceleration of the structure are measured and input to the control device. In the control device, the vibration displacement is also converted into the vibration speed through a differentiator, and the rigidity of the structure and
The vibration characteristics of damping and rigidity are compared with the vibration characteristics of the virtual structure to be realized, and the inertial force to be corrected based on the difference between the two vibration data, that is, the product of the vibration acceleration and the mass, the damping force to be corrected, That is, the product of the vibration speed and the damping and the restoring force to be corrected, that is, the product of the vibration displacement and the rigidity are calculated, and control is performed so that the exciting force of the exciting means, for example, the electromagnet becomes the sum thereof.

The manner in which a structure vibrates when subjected to a certain force depends on the weight of the structure, the rigidity and damping of the support rod, which are the vibration characteristics of the virtual structure to be realized, and this characteristic data is controlled in advance. Input to the device and store it. The controller calculates the excitation force to be applied to the structure from the vibration displacement and vibration acceleration of the structure, but the controller inputs the signals of the displacement meter and the accelerometer, and An operation is performed from the characteristic data and the signal is used to control the electromagnet. The vibration characteristic of the virtual structure to be realized can be freely set as a coefficient in the control device.

Thus, in (2) of the present invention,
As in the invention of (1), it is not necessary to disassemble or replace the experimental device, it is possible to easily cope with the change of the characteristic by changing the coefficient in the control device, and it is possible to obtain an accurate vibration characteristic by calculation. An object can be vibrated.

In (3) of the present invention, the shape of the flow path can be changed by an actuator such as a piezoelectric actuator. This device measures the vibration displacement and vibration acceleration of a structure, inputs it to a control device, and converts the vibration displacement into a vibration speed through a differentiator in the control device. And the vibration characteristics of the virtual structure to be realized, and compare the inertial force to be corrected based on the difference between the two vibration characteristics, that is, the product of the vibration acceleration and the mass, and the damping force to be corrected, that is, the vibration speed and the damping. The product and the restoring force to be corrected, that is, the product of the vibration displacement and the rigidity, are calculated, and the force due to the flow that is changed by changing the flow path shape by the actuator, the so-called fluid force, the inertial force, the damping force, and the restoring to be corrected. Control so that the sum of the forces.

In the above (3) of the present invention,
When the flow path shape is changed, the force due to the flow, that is, the fluid force is measured in advance, and the relationship between the flow path shape and the fluid force is input to the control device and stored. The controller calculates the excitation force to be applied to the structure from the vibration displacement and vibration acceleration of the structure, but the controller inputs the signals of the displacement meter and the accelerometer, and An operation is performed from the characteristic data, and the actuator is controlled by the signal. The vibration characteristic of the virtual structure to be realized can be freely set as a coefficient in the control device. As described above, the effect (3) of the present invention can be the same as the effect (2).

In (4) of the present invention, an electrorheological fluid is used as the fluid. This electrorheological fluid can change the viscosity of the fluid when a voltage is applied. Therefore, a negative electrode and a positive electrode are provided on both sides of the structure and the channel wall, respectively, so that a voltage can be applied to the electrorheological fluid from the control device. When the structure is moving, a force obtained by multiplying the product of the vibration speed of the structure and the viscosity of the fluid by a certain coefficient determined by the flow path shape or the like is applied to the structure. Therefore,
By changing the viscosity of the electrorheological fluid, the force applied to the structure can be changed.

Further, in the above-mentioned device (4) of the present invention,
The vibration displacement and vibration acceleration of the structure are measured, and the control displacement is also converted into the vibration speed through a differentiator, and the vibration characteristics of the rigidity, damping and rigidity of the structure are compared with the vibration characteristics of the virtual structure to be realized. The inertial force to be corrected, that is, the product of vibration acceleration and mass, the damping force to be corrected, that is, the product of vibration speed and damping, and the restoring force to be corrected, that is, the product of vibration displacement and rigidity, Control is performed so that the force applied to the structure when a voltage is applied to the viscous fluid is the sum of the inertial force, the damping force, and the restoring force.

In (4) of the present invention, the relationship between the voltage applied to the electrorheological fluid and the force applied to the structure is determined in advance, and the relationship is input to the control device and stored in advance. The controller calculates the excitation force to be applied to the structure from the vibration displacement and vibration acceleration of the structure, but the controller inputs the signals of the displacement meter and the accelerometer, and An operation is performed from the characteristic data, and a voltage applied to the electrorheological fluid is controlled by the signal. The vibration characteristic of the virtual structure to be realized can be freely set as a coefficient in the control device.

Therefore, according to (4) of the present invention, when changing the characteristics of the structure such as the weight of the structure, the rigidity of the support rod, and the damping, the experiment is performed in the same manner as in the above (2). There is no need to dismantle the device and replace the structure, and it can be easily accommodated by changing the coefficients in the control device. Further, even when an experiment is performed using a fluid different from the actual fluid, it is only necessary to adjust the coefficient in the control device for determining the characteristics of the virtual structure to be realized so as to satisfy the similarity rule.

[0031]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a configuration diagram of a flow vibration experiment apparatus according to a first embodiment of the present invention.
In FIG. 1, in the first embodiment, the flow path wall 1
This is an experimental apparatus in which a structure 3 is arranged so as to receive a flow 2 around it, and a vibration caused by the flow 2 of a virtual structure desired to be realized.

The structure 3 vibrates due to the surrounding flow 2, and its movement is measured by a sensor such as a displacement gauge 6. The structure 3 is attached to the vibrator 7 via the rigid support rod 10 and is vibrated by the vibrator 7. further,
A load cell 11 is provided between the rigid support rod 10 and the vibrator 7 to measure a force applied to the structure 3. The weight of the structure and the rigidity and damping of the flexible support bar, which are the vibration characteristics of the virtual structure to be realized, are input as coefficients of the control device 12.

In this experimental apparatus, there is no flexible support rod, but it is as if the structure 3
Is vibrated so that is connected to the soft support bar. The vibration displacement of the virtual structure to be realized is calculated from the force applied to the structure 3 and the vibration characteristics of the virtual structure to be realized, such as the weight, rigidity, damping, etc., of the structure input using the control device 12. Then, the structure 3 is vibrated by the vibrator 7 so as to have the calculated displacement.

FIG. 2 is a control block diagram according to the first embodiment. The control flow of the control device 12 will be described with reference to FIG. The displacement of the structure 3 is measured by the displacement meter 6.
The force applied to the structure 3 is measured by the load cell 11. The force applied to the structure 3 includes a force applied to the structure 3 by the flow 2 and an inertial force which is a force applied to the structure by vibrating the vibrator 7.

Therefore, the control device 12 first inputs the signal of the displacement meter 6 in S1, calculates the inertia force from the acceleration calculated by differentiating the signal twice and the weight of the structure 3, and
By subtracting this inertial force from the force measured by the load cell 11, the fluid force applied to the structure 3 by the flow is obtained.

Next, in S2, the vibration displacement of the virtual structure to be realized is calculated from the fluid force applied to the structure 3 obtained in S1. At this time, the weight of the structure, the rigidity and the damping of the flexible support bar, which are the vibration characteristics of the virtual structure to be realized in advance, are input as coefficient data 14 into the control device 12.

Next, in the control device 12, the vibration displacement of the virtual structure to be realized calculated in S2 and the displacement meter 6 are calculated.
Is controlled via the servo amplifier 13 to move the vibrator 7 to vibrate the structure 3 so that the displacement actually measured coincides with the displacement.

In the first embodiment, as described above, the force applied to the structure 3 is measured, and the vibration displacement of the virtual structure that is desired to be realized when the force is received is calculated by the control device 12. The exciter 7 is moved so as to have the vibration and the structure 3
Vibrates. It is the control device 12 that calculates the vibration of the virtual structure to be realized from the force applied to the structure 3. The vibration characteristics of the virtual structure to be realized are calculated by the control device 12.
Can be freely set as the coefficient data 14 in.

FIG. 3 is a configuration diagram of a flow vibration experiment apparatus according to a second embodiment of the present invention. In FIG. 3, in the second embodiment of the present invention, similarly to the above-described first embodiment, a structure 3 is arranged so as to be surrounded by a flow path wall 1 and receive a flow 2 around it.
This is an experimental apparatus for examining vibrations caused by a flow 2 of a virtual structure to be realized.

The structure 3 vibrates due to the surrounding flow 2, and its movement is measured by the displacement meter 6 and the accelerometer 16. The structure 3 is fixed by a flexible support bar 4. The weight of the structure 3, the rigidity and damping of the flexible support bar, and the vibration characteristics of the virtual structure to be realized, which are the vibration characteristics of the structure 3, are input as coefficients of the control device 22. The structure 3 can be excited by the electromagnet 15.

In this apparatus, the vibration displacement and vibration acceleration of the structure 3 are measured, and the vibration displacement is also converted into a vibration speed through a differentiator.
By comparing the vibration characteristics of the virtual structure to be realized, the inertial force to be corrected, that is, the product of the vibration acceleration and the mass, and the damping force to be corrected, that is, the product of the vibration speed and the damping, and the restoring force to be corrected, that is, The product of the vibration displacement and the rigidity is calculated, and control is performed so that the exciting force of the electromagnet 15 becomes the sum thereof.

FIG. 4 is a control block diagram according to the second embodiment. The control flow of the control device 22 will be described with reference to FIG. The displacement and acceleration of the structure 3 are measured by the displacement meter 6 and the accelerometer 16. The signal of the displacement meter 6 is also converted by the differentiator 23 into a signal of the vibration velocity. In the inertial force correction calculation unit 22-1, the inertial force to be corrected by multiplying the measured mass by the corrected mass, which is the difference between the mass of the actual structure and the mass of the virtual structure to be realized, that is, the acceleration And the corrected mass.

In the damping force correction calculating section 22-2, the damping force to be corrected by multiplying the corrected damping which is the difference between the damping of the actual structure and the damping of the virtual structure to be realized by the output speed. That is, the product of the speed and the correction attenuation is output.

In the restoring force correction calculating section 22-3, the restoring force to be corrected by multiplying the corrected rigidity, which is the difference between the rigidity of the actual structure and the rigidity of the virtual structure to be realized, by the measured displacement. That is, the product of the displacement and the corrected rigidity is output.

At this time, the weight, the rigidity and the damping of the soft support rod, which are the vibration characteristics of the structure 3 and the virtual structure to be realized, are input as coefficient data 24 into the control device 22 in advance. Then, the sum of the determined inertial force, damping force, and restoring force is output from the exciting force signal generator 25 as an exciting force, and the electromagnet 15 is moved.

FIGS. 5A and 5B show a flow vibration experiment apparatus according to a third embodiment of the present invention. FIG. 5A is an overall configuration diagram, and FIG. In FIG. 5, a third embodiment of the present invention is different from the second embodiment of FIG. 3 in the function and configuration of the flow path wall 1, the flow 2, the structure 3, the displacement gauge 6, the accelerometer 16, and the flexible support rod 4. The same is true. The feature of the third embodiment is that the actuator 21 such as the piezoelectric actuator 17 provided on the structure 3 is used.
Thus, the shape of the flow path can be changed.

In the apparatus according to the third embodiment, FIG.
Is basically the same as the control block shown in FIG.
Also converts the vibration speed through the stiffness, damping,
The rigid vibration characteristics and the vibration characteristics of the virtual structure to be realized are compared, and the inertial force to be corrected, that is, the product of the vibration acceleration and the mass, and the damping force to be corrected, that is, the product of the vibration speed and the damping, and the correction. The restoring force to be obtained, that is, the product of the vibration displacement and the rigidity is calculated. Based on the calculated signal, the control is performed so that the force due to the flow that is changed by changing the flow path shape by the actuator 21, that is, the so-called fluid force becomes the sum of the inertial force, the damping force, and the restoring force to be corrected.

In the third embodiment described above,
When the flow path shape is changed, the force due to the flow, that is, the fluid force is measured in advance, and the relationship between the flow path shape and the fluid force is input to the control device 22 and stored. The above control flow is basically the same as FIG. 4 described in the second embodiment, and instead of the electromagnet 15, the actuator 21
Therefore, detailed description is omitted.

FIG. 6 is a block diagram of a flow vibration experiment apparatus according to a fourth embodiment of the present invention. 6, in the fourth embodiment, the functions and configurations of the flow path wall 1, the flow 2, the structure 3, the displacement gauge 6, the accelerometer 16, and the flexible support bar 4 are the same as those in FIG. The feature of the fourth embodiment is that an electrorheological fluid 18 is used as the fluid.
Use The electrorheological fluid 18 can change the viscosity of the fluid when a voltage is applied. Therefore, a negative electrode 20 and a positive electrode 19 are provided on both sides of the structure 3 and the flow path wall 1, respectively, so that a voltage can be applied to the electrorheological fluid 18.

In the above configuration, when the structure 3 is moving, a force obtained by multiplying the product of the vibration speed of the structure 3 and the viscosity of the fluid by a certain coefficient determined by the shape of the flow path is applied to the structure 3.
Therefore, the force applied to the structure 3 can be changed by changing the viscosity of the electrorheological fluid 18.

The apparatus according to the fourth embodiment is basically the same as the control block shown in FIG. 4, and measures the vibration displacement and the vibration acceleration of the structure 3. The vibration characteristics of the rigidity, damping, and rigidity of the structure are compared with the vibration characteristics of the virtual structure to be realized, and the inertial force to be corrected, that is, the product of the vibration acceleration and the mass, and the damping force to be corrected That is, the product of the vibration speed and the damping and the restoring force to be corrected, that is, the product of the vibration displacement and the rigidity are calculated. Based on the calculated signal, control is performed such that the force applied to the structure 3 when a voltage is applied to the electrorheological fluid 18 via the electrodes 19 and 20 is the sum of the inertial force, the damping force, and the restoring force.

In the fourth embodiment,
The relationship between the voltage applied to the electrorheological fluid 18 and the force applied to the structure 3 is determined in advance, and the relationship is input to the control device 22 and stored in advance. The above control flow is basically the same as that in FIG. 4 described in the second embodiment, and controls the voltage applied to the electromagnetics 19 and 20 instead of the electromagnet 15, and the other components are the same as described above. Therefore, the description is omitted.

[0053]

As described above, according to (1) of the present invention, a vibrator for vibrating a structure, a load meter for measuring a load applied to the structure, and a displacement of the structure. , And the signals measured by the load cell and the displacement meter are input, and the vibration displacement of the virtual structure to be realized is calculated from the previously input vibration characteristic data of the virtual structure to be realized. However, since the configuration is provided with the control device that controls the vibrator so that the calculated vibration displacement is obtained, the following effects are obtained.

(1-1) The vibration characteristics of the structure can be adjusted only by setting the coefficient of the control device. Therefore, when changing the weight of the structure or the rigidity or damping of the soft support rod, there is no need to dismantle the experimental device and replace the structure,
Since it is possible to easily respond by changing the coefficient in the control device, there is an effect that the labor, time and cost required for dismantling the experimental device, replacing the structure, and reassembling the experimental device are eliminated.

(1-2) Even when an experiment is performed using a fluid different from the actual fluid, the similarity rule can be obtained by adjusting the coefficient in the control device that determines the characteristics of the virtual structure to be realized. This has the effect that a satisfactory experiment can be performed.

In (2) of the present invention, the vibration means for vibrating the structure, the accelerometer for measuring the acceleration of the structure, the displacement meter for measuring the vibration displacement of the structure, and the accelerometer and the displacement Input the signal with the gauge, calculate the vibration speed with the differentiator from the signal of the displacement meter, and calculate the weight, damping and rigidity vibration characteristic data of the structure and the vibration characteristic data of the virtual structure to be realized in advance. Then, based on the difference between the two characteristic data, the input vibration displacement of the structure, the calculated vibration speed, and the inertia force, damping force, and restoring force corrected from the input vibration acceleration are calculated, and the calculated values are calculated. And a control device that controls the vibrating means so as to apply a vibrating force to the structure based on the signal from the sum is obtained.

(2-1) A displacement meter is provided in the same manner as in the above invention (1), and an accelerometer is further added. The controller calculates the inertial force, damping force and restoring force to be corrected, and sums them. Control the vibrating means with high-precision calculation,
The same effects as 1) and (1-2) can be obtained, and the labor, time and cost for reassembling the experimental device can be eliminated, and the reliability of the flow vibration experimental device can be further improved.

(2-2) The signals of the displacement meter and the accelerometer are input, and necessary vibration data are input as coefficients, and the inertia force and damping force to be corrected can be corrected only by changing the data.
Since the restoring force is calculated and the control means can accurately control the structure to a desired vibration characteristic based on the signals, the accuracy and reliability of the experimental apparatus are improved.

According to (3) of the present invention, the effect of (2-1) and (2-2) described above is achieved by using a configuration in which the vibrating means is an actuator such as a piezoelectric element in the invention of (2). In addition, since the shape of the flow path can be changed by the actuator, it is possible to change the shape of the flow path by simply moving the actuator, even when performing experiments under different conditions. In addition, the labor, time and cost required for reassembly of the experimental apparatus can be eliminated.

In (4) of the present invention, in the above-mentioned invention of (2), an electrorheological fluid is used as the vibration means and an electrode is provided between the structure and the flow path wall. In addition to the effects of (2-1) and (2-2) above, the viscosity of the fluid can be changed only by changing the voltage applied to the electrorheological fluid. Has the effect that becomes possible. When experimenting with a normal fluid and changing the viscosity of the fluid,
Although the type of the fluid is changed, if the type of the fluid is changed, not only the viscosity but also the density of the fluid is changed, so that it is impossible to change only the viscosity. In (4) of the present invention, only the viscosity of the fluid can be easily changed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a flow vibration experiment device according to a first embodiment of the present invention.

FIG. 2 is a control block diagram of the flow vibration experiment device according to the first embodiment of the present invention.

FIG. 3 is a configuration diagram of a flow vibration experiment device according to a second embodiment of the present invention.

FIG. 4 is a control block diagram of a flow vibration experiment device according to a second embodiment of the present invention.

5A and 5B show a flow vibration experiment apparatus according to a third embodiment of the present invention, wherein FIG. 5A is a configuration diagram, and FIG. 5B is an enlarged view of a portion A of FIG.

FIG. 6 is a configuration diagram of a flow vibration experiment device according to a fourth embodiment of the present invention.

FIG. 7 is a conceptual diagram showing an example of a conventional flow vibration experiment device.

FIG. 8 is a conceptual diagram showing an example of a conventional flow vibration experiment device using a vibrator.

FIG. 9 is a side view showing an example of a conventional flow vibration experiment device using an internal flow of a structure using a vibrator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flow path wall 2 Flow 3 Structure 6 Displacement meter 7 Exciter 10 Rigid support rod 11 Load meter 12, 22, 32, 42 Control device 13 Servo amplifier 14 Coefficient data 15 Electromagnet 16 Accelerometer 17 Piezoelectric actuator 18 Electro-rheological fluid 19 + electrode 20 -electrode 21 actuator 23 differentiator 24 coefficient data 25 excitation force signal generator

Claims (4)

[Claims] A vibrator for vibrating a structure receiving a flow in a fluid flow path; a load meter for measuring a load applied to the structure; a displacement meter for measuring a vibration displacement of the structure; The signals of the load meter and the displacement meter are input, the fluid force due to the flow of the structure is obtained, and the vibration of the virtual structure to be realized is obtained from the fluid force and the vibration characteristic data of the virtual structure to be realized which is input in advance. A flow vibration experiment apparatus, comprising: a controller that calculates a displacement and controls the vibration of the vibrator so that the calculated vibration displacement matches the vibration displacement measured by the displacement meter. 2. Vibration means for vibrating a structure which receives a flow in a fluid flow path; an accelerometer for measuring acceleration of the structure; a displacement meter for measuring vibration displacement of the structure; Input the signals of the displacement meter and the displacement meter, calculate the vibration speed with the differentiator from the signal of the displacement meter, and pre-input the vibration characteristic data of the weight, damping and rigidity of the structure and the vibration of the virtual structure to be realized. Comparing the characteristic data and calculating the inertial force, damping force, and restoring force to be corrected from the input vibration displacement of the structure, the obtained vibration speed, and the input vibration acceleration based on the difference between the two characteristic data. And a control device for controlling the vibrating means so as to apply a vibrating force to the structure based on a signal obtained from the sum of the calculated values. 3. The vibrating means includes an actuator such as a piezoelectric element, and controls a flow rate of the fluid flowing into the structure by changing a flow path of the fluid by the actuator to apply a vibrating force to the structure. The flow vibration experiment apparatus according to claim 2, characterized in that: 4. A structure in which an electrorheological fluid is used as the fluid as the vibration means and electrodes are provided on both sides of the structure and the flow path wall, so that a vibration force is applied to the structure. The flow vibration experiment apparatus according to claim 2, wherein the apparatus is added.