CN114739630B - Flexible wall surface resistance reduction and pulsation pressure reduction effect testing device and application method - Google Patents
Flexible wall surface resistance reduction and pulsation pressure reduction effect testing device and application method Download PDFInfo
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- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
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Abstract
The invention relates to a device for testing the effects of drag reduction and pulsation pressure reduction of a flexible wall surface and a use method thereof, comprising a waterway module, a flexible motion wall surface sensing and actuating unit and a measuring module, wherein a reflux channel of the waterway module comprises a water inlet tank, a water outlet tank, a water pump and a reflux pipeline which are mutually communicated, the flexible motion wall surface sensing and actuating unit comprises a substrate and a skin arranged on the substrate, and a plurality of single dielectric elastomer drivers are arranged on one side of the substrate, which is away from the skin; the flexible motion wall surface sensing actuating unit is arranged at the test section, the measuring device comprises a plurality of sensors, the sensors are arranged at the upstream and downstream of the flexible motion wall surface sensing actuating unit, a laser displacement scanning system is arranged above the test section, and a camera is arranged on the side face of the test section. The invention utilizes the unidirectional dielectric elastomer driver to drive the thin metal plate to realize flexible active deformation, and overcomes the defect that passive flexible wall flow control is only suitable for a certain specific working condition.
Description
Technical Field
The invention relates to the technical field of turbulence control deformation wall testing devices, in particular to a device for testing the effects of reducing drag and reducing pulsation pressure of a flexible wall and a use method thereof.
Background
The marine large-scale fish has remarkable low-resistance low-noise high-efficiency swimming capability, and expert scholars at home and abroad conduct intensive research on the drag-reduction and noise-reduction effects of the fish epidermis, and the drag-reduction and noise-reduction mechanism of the flexible epidermis is primarily obtained by researching the epidermis functions of whale organisms by means of theoretical analysis, numerical calculation, model test and the like. The dolphin skin can be abstracted into a flexible self-adaptive epidermis-turbulence control wall surface, and has the functions of delaying transition, reducing resistance and noise, reducing turbulence burst intensity and the like.
At present, most of researches on the turbulence control wall surface are numerical simulation, the experimental research difficulty is high, and the researches are less. However, numerical simulation needs to simplify boundary conditions, materials and the like, the reliability of the numerical simulation is low, and the correctness of the numerical calculation needs to be verified by means of experiments.
Disclosure of Invention
The applicant provides a flexible wall drag reduction and pulsation pressure reduction effect testing device with reasonable structure and a using method thereof aiming at the defects in the prior art.
The technical scheme adopted by the invention is as follows:
the device for testing the effects of reducing drag and reducing pulsation pressure of the flexible moving wall surface comprises a waterway module, a flexible moving wall surface sensing and actuating unit and a measuring module,
the waterway module comprises a test section, an inflow channel, an outflow channel and a reflux channel which are communicated with each other; the reflux channel comprises a water inlet tank, a water outlet tank, a water pump and a reflux pipeline which are communicated with each other,
the flexible motion wall surface sensing actuating unit comprises a base plate and a skin arranged on the base plate, and a plurality of single dielectric elastomer drivers are arranged on one side of the base plate, which is away from the skin; the flexible motion wall sensing actuation unit is arranged at the test section,
the measuring device comprises a plurality of sensors, the sensors are arranged at the upstream and downstream of the flexible motion wall surface sensing actuating unit, a laser displacement scanning system is arranged above the test section, and a camera is arranged on the side face of the test section.
The flexible motion wall surface sensing actuating unit is clamped by the clamp frame and is arranged on the wall plate of the test section.
The base plate adopts aluminum plate, and the thickness value range is 0.2 ~ 0.5mm.
The skin adopts a silica gel skin, the thickness value range is 0.5-2 mm, and the elastic modulus value range is 0.3-1.0MPa.
The upper surface of the skin is flatly attached to the surface of the substrate, and the edge of the skin is flush with the substrate.
The unidirectional dielectric elastomer drivers are arranged on the substrate in a matrix, and in each row of single dielectric elastomer drivers, a phase difference of 180 degrees exists between the single dielectric elastomer driver in the middle and the single dielectric elastomer drivers at the two sides.
In the longitudinal single dielectric elastomer driver columns, the phase difference between two adjacent single dielectric elastomer drivers is the same.
The flexible motion wall sensing actuation unit is positioned at the center of the test section.
An electromagnetic flowmeter is arranged on the reflux channel.
The application method of the device for testing the effects of reducing drag and reducing pulsation pressure of the flexible moving wall surface comprises the following steps:
and (3) an installation stage: the test section, the inflow channel, the outflow channel and the reflux channel are connected, and the inflow tank, the outflow tank, the water pump and the reflux pipeline are connected to form the reflux channel; pre-installing a flexible motion wall sensing and actuating unit, respectively bonding a skin and a plurality of single dielectric elastomer drivers on two sides of a substrate, clamping the flexible motion wall sensing and actuating unit by a clamp frame, and installing the flexible motion wall sensing and actuating unit on a wall plate of a test section; arranging a scanning system above the test section, and arranging cameras on the side edges of the test section;
testing: inputting driving voltage to the single dielectric elastomer driver, wherein stress and strain exist in the single dielectric elastomer driver and the substrate at the same time, and the flexible motion wall sensing actuating unit presents a deformation mode; different excitation signals are applied to the single-phase dielectric elastomer driver, a conformal wave surface of the spanwise motion is generated on the flexible motion wall surface sensing and braking unit, the excitation frequency is selected from the intermediate value of two adjacent natural frequencies of the flexible motion wall surface, and the natural frequencies are measured by a pre-excitation test; the phase difference of input excitation is related to the arrangement position of excitation points, and the magnitude of the input voltage is related to the wall wave amplitude which is expected to be controlled;
the phase of the unidirectional dielectric elastomer driver corresponds to the following formula:
φ 1 ＝φ 3 ＝0°，φ 2 ＝180°，φ 4 ＝φ 6 ＝γ，φ 5 ＝180°+γ，
wherein phi is the phase of each single dielectric elastomer driver, and gamma is the initial phase value;
setting a control test according to actual needs, wherein the control test comprises a test before a deformation mode and a test after the deformation mode;
the test before the deformation mode is not generated is used for obtaining a shear stress value and a pulsating pressure value of the test surface and a near-wall PIV flow field test structure;
the test after the deformation mode is performed, the laminated plate is driven by the unidirectional dielectric elastomer driver, the waveform of the flexible surface along with the traveling wave is obtained, the traveling wave does not rebound after reaching the boundary, and the shear stress value, the pulsation pressure value and the flow field structure of the deformed surface along with the traveling wave are compared with those of the surface which is not deformed, so that the flow control drag reduction and pulsation pressure reduction effect of the flexible motion wall surface and the related flow mechanism are obtained.
The beneficial effects of the invention are as follows:
compared with a passive flexible surface, the invention has compact and reasonable structure and convenient operation, utilizes the unidirectional dielectric elastomer driver to drive the thin metal plate to realize flexible active deformation, can adaptively control the flow according to the perceived flow information, and realizes concurrent turbulence inhibition, thereby overcoming the defect that the passive flexible wall flow control is only suitable for a certain specific working condition.
Compared with mechanical, electromagnetic and electromechanical servo type driving wall surface deformation, the active mechanical/electromechanical driving mechanism is complex, has large weight, is difficult to seal and is difficult to use in an aqueous medium. The invention adopts the unidirectional dielectric elastomer driver as a novel intelligent material, can be bent greatly, is easy to be adhered to the working surface including curved surfaces, and has the advantages of light weight, small size, low energy consumption and high response speed.
Compared with a wave-surface-static wave-surface wall surface, the flexible wall surface is a wave-surface-moving flexible wall surface, can generate a trailing wave of a spanwise movement, can change the frequency and the amplitude, and is more in line with the movement characteristics of a bionic object.
Drawings
FIG. 1 is an overall structural layout elevation view of the testing apparatus of the present invention.
FIG. 2 is a top view of the overall structural arrangement of the test device of the present invention.
Fig. 3 is a side view of a flow field testing arrangement of the present invention.
Fig. 4 is a back view of the flexible motion wall test of the present invention, showing the test section at a bottom angle.
Fig. 5 is a structural view of the moving wall surface of the present invention.
Fig. 6 is a diagram of a moving wall unidirectional dielectric elastomer actuator arrangement of the present invention.
Wherein: 1. a water inlet tank; 2. a constriction section; 3. a test section; 4. a flexible motion wall sensing actuation unit; 5. a laser displacement scanner; 6. a laser light source; 7. an expansion section; 8. discharging the water tank; 9. a water pump; 10. a flow meter; 11. a return line; 12. a camera;
401. MEMS thermal film shear stress sensor; 402. a pulsed pressure sensor; 403. a unidirectional dielectric elastomer driver; 404. a substrate; 405. and (5) covering.
Detailed Description
The following describes specific embodiments of the present invention with reference to the drawings.
As shown in fig. 1 to 6, the device for testing the effect of reducing drag and reducing pulsation pressure of the flexible moving wall surface of the present embodiment comprises a waterway module, a flexible moving wall surface sensing and actuating unit 4 and a measuring module,
the waterway module comprises a test section 3, an inflow channel, an outflow channel and a reflux channel which are communicated with each other; the return channel comprises a water inlet tank 1, a water outlet tank 8, a water pump 9 and a return pipeline 11 which are communicated with each other,
the flexible motion wall sensing actuation unit 4 comprises a base plate 404 and a skin 405 arranged on the base plate 404, and a plurality of single dielectric elastomer drivers are arranged on one side of the base plate 404 away from the skin 405; a flexible moving wall sensing actuation unit 4 is provided at the test section 3,
the measuring device comprises a plurality of sensors, the sensors are arranged on the upstream and downstream of the flexible motion wall surface sensing actuating unit 4, a laser displacement scanning system is arranged above the test section 3, and a camera 12 is arranged on the side face of the test section 3.
The flexible motion wall surface sensing actuating unit 4 is clamped by the clamp frame and is arranged on the wall plate of the test section 3.
The base plate 404 is made of aluminum plate, and the thickness is in the range of 0.2-0.5 mm.
The skin 405 is a silica gel skin 405, the thickness range is 0.5-2 mm, and the elastic modulus range is 0.3-1.0MPa.
The upper surface of the skin 405 is flush with the surface of the substrate 404, and the edge of the skin 405 is flush with the substrate 404.
The unidirectional dielectric elastomer drivers 403 are disposed on the substrate 404 in a matrix, and in each row of the single dielectric elastomer drivers, a phase difference of 180 ° exists between the single dielectric elastomer driver in the middle and the single dielectric elastomer drivers on both sides.
In the longitudinal single dielectric elastomer driver columns, the phase difference between two adjacent single dielectric elastomer drivers is the same.
The flexible moving wall surface sensing actuation unit 4 is located at the center of the test section 3.
An electromagnetic flowmeter 10 is arranged on the return channel.
The application method of the flexible motion wall surface drag reduction and pulsation reduction pressure effect testing device comprises the following steps:
and (3) an installation stage: the test section 3, the inflow channel, the outflow channel and the reflux channel are connected, and the water inlet tank 1, the water outlet tank 8, the water pump 9 and the reflux pipeline 11 are connected to form a reflux channel; pre-installing a flexible motion wall sensing and actuating unit 4, respectively adhering a skin 405 and a plurality of single dielectric elastomer drivers to two sides of a substrate 404, clamping the flexible motion wall sensing and actuating unit 4 by a clamp frame, and installing the flexible motion wall sensing and actuating unit 4 on a wall plate of a test section 3; a scanning system is arranged above the test section 3, and a camera 12 is arranged at the side edge of the test section 3;
testing: inputting a driving voltage to the single dielectric elastomer driver, wherein stress and strain exist in the single dielectric elastomer driver and the substrate 404 at the same time, and the flexible motion wall sensing actuation unit 4 presents a deformation mode; different excitation signals are applied to the single-phase dielectric elastomer driver, a conformal wave surface of the spanwise motion is generated on the flexible motion wall surface sensing and braking unit, the excitation frequency is selected from the intermediate value of two adjacent natural frequencies of the flexible motion wall surface, and the natural frequencies are measured by a pre-excitation test; the phase difference of input excitation is related to the arrangement position of excitation points, and the magnitude of the input voltage is related to the wall wave amplitude which is expected to be controlled;
the phase of the unidirectional dielectric elastomer driver corresponds to the following formula:
φ 1 ＝φ 3 ＝0°，φ 2 ＝180°，φ 4 ＝φ 6 ＝γ，φ 5 ＝180°+γ，
wherein phi is the phase of each single dielectric elastomer driver, and gamma is the initial phase value;
setting a control test according to actual needs, wherein the control test comprises a test before a deformation mode and a test after the deformation mode;
the test before the deformation mode is not generated is used for obtaining a shear stress value and a pulsating pressure value of the test surface and a near-wall PIV flow field test structure;
the test after the deformation mode is performed, the laminated plate is driven by the unidirectional dielectric elastomer driver 403, the waveform of the flexible surface along with the traveling wave is obtained, the traveling wave does not rebound after reaching the boundary, and the shear stress value, the pulsation pressure value and the flow field structure of the deformed surface along with the traveling wave are compared with those of the surface which is not deformed, so that the flow control drag reduction, the pulsation pressure reduction effect and the related flow mechanism of the flexible motion wall surface are obtained.
According to the turbulence control flexible motion wall surface, the amplitude and frequency adjustable spreading direction following wave surface is generated by adjusting the input voltage signal of the unidirectional dielectric elastomer driver, the MEMS thermal film sensors and the pulse pressure sensors are uniformly distributed in front of and behind the flexible motion wall surface, and the controller adjusts the control voltage according to the signals fed back by the flexible motion wall surface rear sensor and the pulse pressure sensor, so that the drag reduction and pulse pressure reduction effects of the flexible motion wall surface in different motion forms can be tested, and the operation is convenient.
The specific structure and working process of this embodiment are as follows:
the whole device comprises a waterway module, a measuring module and a flexible motion wall surface sensing actuating unit 4, wherein the waterway module comprises a test section 3, an inflow channel, an outflow channel and a reflux channel, the inflow channel is a stable contraction section 2, and the outflow channel is an expansion transition section. The inflow channel and the outflow channel are both communicated with the test section 3. The return channel comprises a water inlet tank 1, a water outlet tank 8 and a water pump 9, which are communicated through a return pipeline 11. An electromagnetic flowmeter 10 is mounted on the return channel for monitoring the flow in the channel.
The measuring module comprises a MEMS thermal film sensor and a pulse pressure sensor 402, which are respectively arranged at the upstream and downstream of the flexible motion wall surface sensing actuating unit 4 and are used for measuring the shear stress value and the pulse pressure value of the front and the back of the flexible motion wall surface in real time. Meanwhile, a laser displacement scanning measurement system is distributed above the test section 3 to measure micro-displacement of the deformed wall surface; a laser light source 6 is also arranged for illuminating the sheet light. The side face of the test section 3 is provided with a high-speed camera 12 for taking images of particle image velocimetry PIV flow field images. The structure enables the flow field real-time measurement in the flexible motion wall surface motion process to be possible by adding a non-contact data acquisition means outside the MEMS surface thermal film sensor and the pulse pressure sensor 402, namely, the space-time correlation of the flow field, the shear stress and the pulse pressure can be analyzed by monitoring data.
The flexible motion wall sensing and actuating unit 4 is composed of a plurality of unidirectional dielectric elastomer drivers 403, DEA (Dielectric Elastomers Actuators), a metal substrate 404 and a silica gel skin 405, wherein the unidirectional dielectric elastomer drivers 403 are adhered to the upper surface of the metal substrate 404 by epoxy glue, and the silica gel skin 405 is adhered to the lower surface of the metal substrate 404, so that the flexible motion wall sensing and actuating module, namely the laminated board, is formed by the three components together. The flexible moving wall surface is clamped by a metal clamp frame and is arranged on the upper wall plate of the test section 3.
The thickness of the metal substrate 404 is 0.2 mm-0.5 mm, in this embodiment, the metal substrate 404 is an aluminum plate, and the thickness can be 0.2mm, 0.5mm, or 0.3mm.
The thickness of the silica gel skin 405 is 0.5-2 mm, the elastic modulus is 0.3-1.0MPa, and the thickness is 1mm and the elastic modulus is 0.5MPa in the embodiment;
the unidirectional dielectric elastomer driver 403 is mounted above the metal substrate 404 and keeps the upper surface of the silicone skin 405 flush with the carrier surface, as shown in fig. 4, one to avoid large flow resistance from the protruding portion and the other to minimize the load carried by the actuator.
After the installation is completed, driving voltage is input to the unidirectional dielectric elastomer driver 403, and stress and strain exist in the unidirectional dielectric elastomer driver 403 and the metal substrate 404 at the same time, and as the whole flexible moving wall surface is fixed by the metal clamp frame, the whole flexible moving wall surface can present different deformation modes under the restraint of the actuating force of the unidirectional dielectric elastomer driver 403 and the clamp frame, and different excitation signals are applied to the unidirectional dielectric elastomer driver 403 to move the wall surface; i.e. a trailing wave surface that produces spanwise motion on the wall surface formed by the silicone skin 405, the metal substrate 404, the unidirectional dielectric elastomer driver 403.
The frequency of the excitation is preferably selected from the intermediate value of two adjacent natural frequencies of the flexible moving wall surface, the phase difference of the input excitation is closely related to the arrangement position of the excitation points, and the magnitude of the input voltage is related to the wall surface wave amplitude which is expected to be controlled.
Since the magnitude of the motion follower wave is proportional to the magnitude of the applied voltage, the larger the applied voltage is, the larger the generated spanwise follower wave amplitude is within the allowable voltage range.
The flexible silicon rubber skin 405 is adhered to the lower surface of the metal substrate 404, so that the flexible moving wall surface can release incoming flow pressure while deforming and moving, and the effects of reducing resistance and impulse pressure excitation are achieved. In order to prevent wrinkles from occurring on the upper surface of the sports board, the initial film should be suitably pre-tensioned when being stuck.
In addition, the voltage excitation frequency should be selected to be the intermediate frequency between two adjacent natural frequencies of the flexible motion wall surface actuating module, and the natural frequency of the flexible motion wall surface actuating module can be measured by an excitation test in advance.
The unidirectional dielectric elastomer drivers 403 disposed on the metal substrate 404 on the left and right sides have the same phase, as shown in fig. 5, the middle unidirectional dielectric elastomer drivers 4032 and 5 have an additional 180 ° phase difference with the unidirectional dielectric elastomer drivers 403 on the left and right sides, and the unidirectional dielectric elastomer drivers 4031-4,2-5,3-6 have the same phase difference, and the phases of the 6 unidirectional dielectric elastomer drivers 403 are as follows.
φ 1 ＝φ 3 ＝0°，φ 2 ＝180°，φ 4 ＝φ 6 ＝γ，φ 5 ＝180°+γ
To sum up, the present embodiment generates a trailing wave along the spanwise direction with controllable waveform parameters on the flat substrate 404.
In this embodiment, the MEMS thermal film sensor and the pulsating pressure sensor 402 are disposed at the front and rear sides of the flexible moving wall, that is, at the upstream and downstream positions, the sensor senses the change of the flow state, the front MEMS sensor and the pulsating pressure sensor 402 acquire the shear stress value, the temperature value and the incoming flow velocity value of the incoming flow wall, the pulsating pressure value identifies the flow state of the incoming flow, and the MEMS shear stress sensor and the microphone disposed at the rear can measure the influence area controlled by the flexible moving wall, and test the drag reduction and the pulsation pressure reduction effects of different moving follower surfaces by changing the motion parameters of the spanwise follower surfaces.
The test device can perform a control test, firstly, a test before deformation of the laminated board is performed, a shear stress value and a pulsation pressure value of a test surface and a near-wall PIV flow field test structure can be obtained, then, a movement following traveling wave surface test after deformation is performed, the laminated board is driven by a unidirectional dielectric elastomer driver 403, a flexible surface following traveling wave waveform is obtained, no rebound occurs after a following wave reaches a boundary, and the shear stress value, the pulsation pressure value and the flow field structure of the deformed following wave surface are compared with the non-deformed surface, so that a flexible movement wall flow control drag reduction, a pulsation pressure reduction effect and a related flow mechanism can be obtained. The electric signals input are changed, so that the effects of reducing drag and reducing pulsation pressure of different flexible motions along with the surface of the traveling wave can be obtained.
The above description is intended to illustrate the invention and not to limit it, the scope of which is defined by the claims, and any modifications can be made within the scope of the invention.
Claims (9)
1. The application method of the device for testing the effects of reducing drag and reducing pulsation pressure on the flexible moving wall surface is characterized by comprising the following steps of: the device for testing the effects of reducing drag and reducing pulsation pressure of the flexible moving wall surface comprises a waterway module, a flexible moving wall surface sensing and actuating unit (4) and a measuring module,
the waterway module comprises a test section (3), an inflow channel, an outflow channel and a reflux channel which are communicated with each other; the reflux channel comprises a water inlet tank (1), a water outlet tank (8), a water pump (9) and a reflux pipeline (11) which are communicated with each other,
the flexible motion wall surface sensing actuating unit (4) comprises a base plate (404) and a skin (405) arranged on the base plate (404), wherein a plurality of single-phase dielectric elastomer drivers are arranged on one side of the base plate (404) away from the skin (405); the flexible motion wall sensing actuating unit (4) is arranged at the test section (3),
the measuring module comprises a plurality of sensors which are arranged at the upstream and downstream of the flexible motion wall surface sensing actuating unit (4), a scanning system is arranged above the test section (3), a camera (12) is arranged on the side surface of the test section (3),
the using method of the device for testing the effects of reducing drag and reducing pulsation pressure on the flexible moving wall surface is as follows:
and (3) an installation stage: the test section (3), the inflow channel, the outflow channel and the reflux channel are connected, and the reflux channel is formed by connecting the water inlet tank (1), the water outlet tank (8), the water pump (9) and the reflux pipeline (11); the flexible motion wall surface sensing actuating unit (4) is pre-installed, the skin (405) and the plurality of single dielectric elastomer drivers are respectively adhered to two sides of the base plate (404), and the flexible motion wall surface sensing actuating unit (4) is clamped and installed on the wall plate of the test section (3) by adopting the clamp frame; the upper surface of the silica gel skin (405) is kept level with the surface of the carrier, so that the flow resistance caused by the protruding part is avoided, and the load born by the actuator is reduced; the silica gel skin (405) plays a role in releasing incoming flow pressure, reducing resistance and reducing impulse pressure excitation; and the pre-tensioning should be carried out during the pasting,
a laser displacement scanning system is arranged above the test section (3), and a camera (12) is arranged at the side edge of the test section (3);
testing: inputting driving voltage to the single dielectric elastomer driver, wherein stress and strain exist in the single dielectric elastomer driver and the substrate (404) at the same time, and the flexible motion wall sensing actuating unit (4) presents a deformation mode; different excitation signals are applied to the single-phase dielectric elastomer driver, a conformal wave surface of the spanwise motion is generated on the flexible motion wall surface sensing and braking unit, the excitation frequency is selected from the intermediate value of two adjacent natural frequencies of the flexible motion wall surface, and the natural frequencies are measured by a pre-excitation test; the phase difference of input excitation is related to the arrangement position of excitation points, and the magnitude of the input voltage is related to the wall wave amplitude which is expected to be controlled;
the phase of the unidirectional dielectric elastomer driver corresponds to the following formula:
，/>，/>，/>
wherein phi is the phase of each single dielectric elastomer driver, and gamma is the initial phase value;
setting a control test according to actual needs, wherein the control test comprises a test before a deformation mode and a test after the deformation mode;
the test before the deformation mode is not generated is used for obtaining a shear stress value and a pulsating pressure value of the test surface and a near-wall PIV flow field test structure;
the test after the deformation mode is performed, the laminated plate is driven by a unidirectional dielectric elastomer driver (403), the waveform of the flexible surface along with the traveling wave is obtained, the traveling wave does not rebound after reaching the boundary, and the shear stress value, the pulsation pressure value and the flow field structure of the deformed surface along with the traveling wave are compared with those of the surface which is not deformed, so that the flow control drag reduction, pulsation pressure reduction effect and related flow mechanism of the flexible motion wall surface are obtained; the whole flexible moving wall surface can present different deformation modes under the constraint of the actuating force of the unidirectional dielectric elastomer driver (403) and the clamp frame;
the MEMS thermal film sensor (401) and the pulse pressure sensor (402) are arranged on the front side and the rear side of the flexible motion wall surface, the MEMS thermal film sensor and the pulse pressure sensor (402) at the front part acquire an incoming flow wall surface shear stress value, a temperature value and an incoming flow speed value, the pulse pressure value identifies the flowing state of incoming flow, the MEMS thermal film sensor (401) and the pulse pressure sensor (402) arranged at the rear part measure the influence area of the flexible motion wall surface control, and the resistance reduction and the pulse pressure reduction effects of different motion follower surfaces are tested by changing the motion parameters of the spread follower surfaces.
2. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 1, wherein the method comprises the following steps: the flexible motion wall surface sensing actuating unit (4) is clamped by the clamp frame and is arranged on the wall plate of the test section (3).
3. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 2, wherein the method comprises the following steps: the substrate (404) adopts an aluminum plate, and the thickness range is 0.2-0.5 mm.
4. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 1, wherein the method comprises the following steps: the skin (405) is a silica gel skin (405), the thickness range is 0.5-2 mm, and the elastic modulus range is 0.3-1.0MPa.
5. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 4, wherein the method comprises the following steps: the upper surface of the skin (405) is flatly attached to the surface of the substrate (404), and the edge of the skin (405) is flush with the substrate (404).
6. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 1, wherein the method comprises the following steps: the unidirectional dielectric elastomer drivers (403) are arranged on the substrate (404) in a matrix, and in each row of the single dielectric elastomer drivers, a phase difference of 180 degrees exists between the single dielectric elastomer driver in the middle and the single dielectric elastomer drivers on the two sides.
7. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 6, wherein the method comprises the following steps: in the longitudinal single dielectric elastomer driver columns, the phase difference between two adjacent single dielectric elastomer drivers is the same.
8. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 1, wherein the method comprises the following steps: the flexible motion wall surface sensing actuating unit (4) is positioned at the center of the test section (3).
9. The method for using the flexible motion wall drag reduction and pulsation reduction pressure effect testing device according to claim 1, wherein the method comprises the following steps: an electromagnetic flowmeter (10) is arranged on the reflux channel.
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