Experimental device and method for researching high-rotation-speed instability interval of rotor oil

Abstract

The invention discloses an experimental device and method for researching a high-rotating-speed instability interval of rotor oil. The experimental device comprises a frame, a rotating shaft, an oil tank, a first bearing, a second bearing, a storage plate, a plurality of partition plates and a processor. Round holes are formed in the middle of the top plate and the middle of the storage plate. The first bearing and the second bearing are installed in the round holes of the storage plate and the top plate of the frame through the first bearing seat and the second bearing seat respectively. The rotating shaft vertically penetrates through the first bearing and the second bearing from top to bottom, is connected with the oil tank located between the storage plate and the bottom plate and carries the oil tank to horizontally rotate under the action of the motor. One end of each partition plate is connected with a stand column located in the center of the oil tank, the other end of each partition plate is connected with the inner side face of the oil tank, and the oil tank is evenly divided into a plurality of sub-areas. The device can effectively simulate the vibration phenomenon of oil under the condition of the baffle, the baffle is convenient to assemble and disassemble, and the device is suitable for related research of rotor dynamics about oil rotation vibration.

Description

Technical Field

[0001] The invention belongs to the technical field of vibration testing, and in particular relates to an experimental device and method for studying a high-speed instability range of rotor oil. Background Art

[0002] In the field of high-speed rotating machinery research, the dynamic stability of aircraft engine systems has always been a key research issue. When the rotor speed increases, instability and instability are inevitable.

[0003] In the past decade, due to the needs of the industrial sector, especially the aviation sector, rotating machinery has been developed for a long time, and rotor dynamics, as an important research of rotating machinery, has also attracted much attention. As the rotor develops towards large size, heavy load, and high speed, it brings many instability phenomena, so ensuring the stability of the rotor system operation has become an important task of rotor dynamics.

[0004] Aircraft engines are inevitably filled with a viscous and incompressible liquid, namely oil accumulation, during operation. The accumulation of oil will cause the engine disturbance amplitude to increase exponentially. At a certain speed, due to the interaction between solids and liquids, a fluid-solid coupling phenomenon is formed. Also, due to the coupling of friction and gyroscopic forces, the rotor becomes unstable at a certain speed and has an unstable range. In order to explore the unstable range and study the laws and principles of rotor instability, this patent has built an experimental device to study the high-speed instability range of rotor oil, and then study the influence of aircraft engine dynamic parameters on stability, revealing the instability mechanism of aircraft engines.

[0005] The Chinese patent with patent application number 2023106157250 discloses a rotor oil accumulation test device to solve the problem of warm high-speed rotor stator friction test. This patent has shortcomings when used. First, it is difficult to assemble when assembling oil; second, it is impossible to add baffles to change the baffle parameters. The above shortcomings make the device unable to simulate the vibration phenomenon of oil in the case of baffles. Summary of the invention

[0006] Technical problem to be solved: The present invention proposes an experimental device and method for studying the high-speed instability range of rotor oil, which can effectively simulate the vibration phenomenon of oil under different baffle conditions, and the baffle is easy to load and unload, and is suitable for relevant research on rotor dynamics about oil rotational vibration.

[0007] Technical solution:

[0008] In a first aspect, the present invention discloses an experimental device for studying the high-speed instability range of rotor oil, the experimental device comprising a frame, a rotating shaft, an oil tank, a first bearing, a second bearing, a storage plate, a plurality of partitions and a processor;

[0009] The frame is composed of four square columns and a top plate and a bottom plate parallel to each other; the storage plate is installed in the middle of the frame; the first bearing and the second bearing are installed on the storage plate and the top plate of the frame through the first bearing seat and the second bearing seat respectively;

[0010] A circular hole is provided between the top plate and the storage plate, and the first bearing and the second bearing are respectively installed in the circular holes of the storage plate and the top plate of the frame through the first bearing seat and the second bearing seat; the rotating shaft vertically passes through the first bearing and the second bearing from top to bottom, and is connected to the oil tank located between the storage plate and the bottom plate, and carries the oil tank to rotate horizontally under the action of the motor;

[0011] The plurality of partitions are detachably and evenly distributed in the oil tank, one end of the partition is connected to a column located in the center of the oil tank, and the other end is connected to the inner side of the oil tank, so as to evenly divide the oil tank into a plurality of sub-areas; water or oil is poured into the oil tank;

[0012] For the two oil tank states of no baffle installed in the oil tank and different numbers of baffles installed in the oil tank, the processor controls the motor to drive the shaft to rotate and gradually increase the shaft speed from 0 to a stable state, so that the oil in the oil tank vibrates violently, records the rotor speed in the stable state, and drives the displacement sensor and vibration sensor fixed on the shaft to record the displacement parameters and vibration parameters of the shaft in real time during the speed increase, and drives the high-speed camera to take a vibration image of the oil in the oil tank in real time; the processor performs time domain analysis on the displacement parameters and vibration parameters to generate a vibration state waveform diagram, obtains the corresponding spectrum diagram through Fourier transform, analyzes the spectrum diagram, and obtains frequency components and harmonic components related to the vibration signal. If the rotor displacement increases sharply, it is considered that the rotor system is unstable; combined with the rotor speed in the stable state and the vibration image of the oil, the rotor stability and the oil vibration law are analyzed. If the oil image undergoes a modal transition, it is considered that the rotor is unstable, and then the rotor oil high speed instability range is obtained.

[0013] Furthermore, the storage plate is installed in the middle of the frame through a stabilizing member; the stabilizing member is a rectangular steel plate with a square hole in the middle, the size of the stabilizing member is consistent with the outer size of the frame, and there are screw holes on the side corresponding to the side screw holes of the square columns of the frame.

[0014] Furthermore, a circular hole with a diameter of 20 mm is opened between the top plate and the storage plate.

[0015] Further, the rotating shaft is a cylindrical steel column with a thread at one end;

[0016] The oil tank is provided with an oil tank top cover, the inner diameter of the oil tank top cover is consistent with the outer diameter of the oil tank, and a screw hole corresponding to the rotating shaft thread is arranged at the center of the oil tank top cover.

[0017] Furthermore, the oil tank adopts a transparent disc with a central groove, and a column is fixed to the bottom of the oil tank in the center of the oil tank. The bottom of the column is cylindrical, and the upper end of the column is a square column, and the diagonal length of the square column is less than the diameter of the cylinder.

[0018] Furthermore, three partitions or six partitions are evenly installed in the oil tank.

[0019] In a second aspect, the present invention discloses an experimental method for studying the high-speed instability range of rotor oil based on the above-mentioned experimental device, and the experimental method comprises the following steps:

[0020] S1: Establish rotor oil accumulation fault model based on NS equation;

[0021] S2: Keep the oil tank still and pour water or oil into the oil tank without partition;

[0022] S3: The motor drives the rotor to rotate, increasing its speed from 0 to a preset stable state, recording the parameters of the rotor and oil during the increase, recording the rotor speed in the stable state, and turning off the motor;

[0023] S4: Based on the rotor speed in the stable state and the rotor oil accumulation fault model, the rotor stability is analyzed and the oil vibration parameters are recorded;

[0024] S5: repeating steps S2 to S4, if the analysis results of the vibration law of the rotor oil are the same twice, proceeding to step S6; otherwise, repeating steps S2 to S4 until the analysis result of the vibration law of the rotor oil is the same as that of step S4;

[0025] S6, adding multiple baffles to the oil tank, executing steps S3 to S4, analyzing and obtaining the vibration law of the oil under different baffle conditions, and obtaining the high-speed instability range of the rotor oil.

[0026] Step S1 further comprises the following steps:

[0027] List the frequency equation for a radial circular surface wave:

[0028]

[0029] When w≠0, an axial circular surface wave appears; the value of the cyclic characteristic frequency of the two-dimensional surface wave is:

[0030]

[0031] in represents the positive vortex frequency of the fluid, Represents the reverse vortex frequency of the fluid.

[0032] Furthermore, the experimental method further comprises the following steps:

[0033] Based on the forward and reverse vortex frequencies of the fluid at different frequencies obtained in step S1, the intersection of the forward and reverse vortex frequencies and the critical instability line is regarded as instability, and a theoretical instability interval is obtained;

[0034] The rotor instability interval obtained from the frequency spectrum in step S6 is compared with the theoretical instability interval to determine whether the experimental instability interval is consistent with the calculated instability interval.

[0035] Beneficial effects:

[0036] The experimental device for studying the high-speed instability interval of rotor oil and the method for calculating the rotor instability interval of the present invention can effectively simulate the vibration phenomenon of oil in the presence of a baffle, and the baffle is convenient to load and unload. At the same time, theory and experiment verify each other, which is suitable for effectively monitoring the rotational vibration of oil in rotor dynamics. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of an experimental device for studying the high-speed instability range of rotor oil according to the present invention;

[0038] Figure 2 A schematic diagram of the framework;

[0039] Figure 3 It is a schematic diagram of the bearing seat;

[0040] Figure 4 is a schematic diagram of a bearing;

[0041] Figure 5 This is a schematic diagram of the fuel tank;

[0042] Figure 6 This is a schematic diagram of the fuel tank top cover;

[0043] Figure 7 It is a schematic diagram of three partitions;

[0044] Figure 8 It is a schematic diagram of six partitions;

[0045] Fig. 9 Schematic diagram of the rotor chamber partially filled with fluid without baffles (left) and with baffles (right) in the case of self-excitation of a first-order radial circular wave (j=1);

[0046] Fig.10 Schematic diagram of the cyclic frequency of the basic radial circular surface wave (single node) with no baffle (Ω1), three baffles (Ω3) and six baffles (Ω6), where represents the positive vortex frequency of the fluid, Represents the reverse vortex of the fluid; where (a) represents the forward and reverse vortex frequency of the fluid at different radial directions, (b) represents the forward and reverse vortex frequency of the fluid at different frequencies, and instability occurs at the intersection with the critical instability line. DETAILED DESCRIPTION

[0047] The following examples will enable those skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0048] See also Figure 1 , the present invention discloses an experimental device for studying the high-speed instability range of rotor oil, the experimental device comprising a frame, a rotating shaft, an oil tank, a first bearing, a second bearing, a storage plate, a plurality of partitions and a processor;

[0049] The frame is composed of four square columns and a top plate and a bottom plate parallel to each other; the storage plate is installed in the middle of the frame; the first bearing and the second bearing are installed on the storage plate and the top plate of the frame through the first bearing seat and the second bearing seat respectively;

[0050] A circular hole is provided between the top plate and the storage plate, and the first bearing and the second bearing are respectively installed in the circular holes of the storage plate and the top plate of the frame through the first bearing seat and the second bearing seat; the rotating shaft vertically passes through the first bearing and the second bearing from top to bottom, and is connected to the oil tank located between the storage plate and the bottom plate, and carries the oil tank to rotate horizontally under the action of the motor;

[0051] The plurality of partitions are detachably and evenly distributed in the oil tank, one end of the partition is connected to a column located in the center of the oil tank, and the other end is connected to the inner side of the oil tank, so as to evenly divide the oil tank into a plurality of sub-areas; water or oil is poured into the oil tank;

[0052] For the two oil tank states of no baffle installed in the oil tank and different numbers of baffles installed in the oil tank, the processor controls the motor to drive the shaft to rotate and gradually increase the shaft speed from 0 to a stable state, so that the oil in the oil tank vibrates violently, records the rotor speed in the stable state, and drives the displacement sensor and vibration sensor fixed on the shaft to record the displacement parameters and vibration parameters of the shaft in real time during the speed increase, and drives the high-speed camera to take a vibration image of the oil in the oil tank in real time. The processor performs time domain analysis on the displacement parameters and vibration parameters to generate a vibration state waveform diagram, obtains the corresponding spectrum diagram through Fourier transform, analyzes the spectrum diagram, and obtains frequency components and harmonic components related to the vibration signal. If the rotor displacement rises sharply, it is considered that the rotor system is unstable. Combined with the rotor speed in the stable state and the vibration image of the oil, the rotor stability and the oil vibration law are analyzed. If the oil image undergoes a modal transition, it is considered that the rotor is unstable, thereby obtaining the high-speed instability interval of the rotor oil.

[0053] In terms of experimental device structure, it is preferred to refer to Figure 2 The frame is composed of four square columns and parallel top and bottom plates. The two ends of the four columns are fixedly connected to the four corners of the upper bottom plate and the lower bottom plate respectively; the top plate is a rectangular steel plate with a hole in the center of the top plate with a diameter of 20mm. There are a certain number of screw holes on one side of the hole. There are screw holes on the top surface of the top plate for connecting the motor, and there is an opening in the middle of the top plate for passing the rotating shaft; there is a screw hole in the middle of one side of the column for connecting the stabilizer.

[0054] The stabilizer is used to support the storage plate on the four columns of the steel frame. The stabilizer is a rectangular steel plate with a square hole in the middle. The size is consistent with the column of the frame. There are screw holes on the side that are consistent with the screw holes on the side of the column of the frame. It is used to be installed on the column of the steel frame. The storage plate is a rectangular steel plate with the same size as the upper and lower bottom plates of the steel frame. There is a small circular hole with a diameter of 20mm in the middle. There are also a preset number of screw holes in the center of the storage plate for fixing the bearing seat. The storage plate has holes at the four corners. The shape of each hole corresponds to the cross-section of the column of the frame. The columns of the frame pass through the holes at the four corners of the storage plate, so that the storage plate is fixed between the top plate and the bottom plate of the frame; there are screw holes on the storage plate. The positions of each screw hole correspond to the screw holes on the stabilizer, so that the storage plate is fixed on the stabilizer by screws. The shaft is a cylindrical steel column with a thread at one end.

[0055] Figure 3 and Figure 4 The figure is a schematic diagram of the bearing seat and the bearing used in the present invention. The bearing seat is a device for connecting the bearing, and its base is a rectangular structure with screw holes at four corners. The screw holes of the bearing seat base correspond to the screw holes of the device plate, and the bearing seat and the device plate are fixedly connected by screws; the bearing is connected to the bearing seat and connected to the oil tank through the rotating shaft. When the rotor is driven by the motor, the oil tank rotates driven by the rotating shaft.

[0056] like Figure 5 As shown, the fuel tank is a cylindrical transparent disc with a groove in the middle. There is an external thread on the outside of the fuel tank for connecting the fuel tank top cover. There is a cylindrical boss in the center of the disc. The top of the cylindrical boss is changed to a rectangular boss for installing and fixing various partitions. Each partition is made of a square plate with a size that fits the inner diameter of the fuel tank and a hole in the middle. The square hole is opened in the middle first and then the cylindrical groove is opened so that the partition can be assembled with the fuel tank.

[0057] like Figure 6 As shown, the top cover of the oil tank is a cylindrical disc with a cylindrical groove in the middle and a spiral groove on the inside. It is connected to the oil tank through a thread. A cylindrical through hole is opened in the middle of the top cover disc. The inner wall of the hole has an internal thread, which corresponds to the thread of the shaft. There is a raised part in the center of the oil tank for connecting the partition. The oil tank is designed to be detachable in order to facilitate the placement and replacement of the partition. There are screw holes on the top cover to connect to the rotor. The thread direction should be opposite to the thread direction at the connection between the oil tank and the top cover.

[0058] There is an opening in the center of the partition corresponding to the center column of the oil tank, and the partition can be connected to the center of any piece. Figure 7 It is a schematic diagram of three partitions; Figure 8 This is a schematic diagram of six partitions. In practical applications, other numbers of partitions can be installed, and holes are left in the middle of the partitions to fix them to the oil tank, making loading and unloading convenient.

[0059] During the experiment, first connect the device correctly, install the storage plate in the middle of the frame through the stabilizer, install one bearing seat on the storage plate and one on the top of the frame, fix the motor on the top of the frame, connect the oil tank cover to the oil tank and the rotating shaft, the rotating shaft is connected to the motor through two bearing seats, and the partition can be installed in the oil tank. Open the oil tank and fill a certain amount of water or oil in the oil tank. Connect the oil tank to the rotor. Fix the photosensitive strip on the rotor, fix the displacement sensor and vibration sensor on the device, and connect the other end to the computer to capture the vibration amplitude acceleration. Fix the high-speed camera under the storage table to capture the state of the oil in the oil tank at a certain moment. After that, turn on the motor, the rotor rotates, and gradually increase the speed. The liquid in the oil tank begins to vibrate with the oil tank and vibrates violently at certain moments. According to the changes in displacement and acceleration captured by the computer, do time domain analysis, and make a waveform diagram of the vibration state, and make a spectrum diagram after Fourier transform. Perform autocorrelation processing on the spectrum diagram to simplify the results and analyze which frequency components and harmonic components the vibration signal consists of. The amplitude of the harmonic component is the most prominent, which may be related to the fault. The state of the fuel tank under forced vibration resonance is captured by a high-speed camera, and the experimental data is recorded to further analyze the mechanism. Finally, different numbers of partitions are replaced to study and analyze the vibration state of the oil under the partition state.

[0060] The present invention discloses an experimental method for studying the high speed instability range of rotor oil based on the above-mentioned experimental device, and the experimental method comprises the following steps:

[0061] S1: Establish rotor oil accumulation fault model based on NS equation;

[0062] S2: Keep the oil tank still and pour water or oil into the oil tank without partition;

[0063] S3: The motor drives the rotor to rotate, increasing its speed from 0 to a preset stable state, recording the parameters of the rotor and oil during the increase, recording the rotor speed in the stable state, and turning off the motor;

[0064] S4: Based on the rotor speed in the stable state and the rotor oil accumulation fault model, the rotor stability is analyzed and the oil vibration parameters are recorded;

[0065] S5: repeating steps S2 to S4, if the analysis results of the vibration law of the rotor oil are the same twice, proceeding to step S6; otherwise, repeating steps S2 to S4 until the analysis result of the vibration law of the rotor oil is the same as that of step S4;

[0066] S6, adding multiple baffles to the oil tank, executing steps S3 to S4, and analyzing and obtaining the vibration law of the oil under different baffle conditions.

[0067] The method of theoretically establishing a theoretical model in step S1 is as follows:

[0068] Assuming that the fluid motion is perturbed by a small lateral deflection of the rotor and is periodic in time, the values ​​characterizing the fluid oscillations in the circumferential and axial directions are proportional to exponential functions, for example, the perturbation pressure is:

[0069]

[0070] In the formula, the period T rθ is the length of a radial-circular wave with a period of T z is the length of a radial-axial wave.

[0071]

[0072] Where λ k represents the arc length of the circular wave. Where j is the number of nodes or wave crests along the circular motion of the rotating fluid in the n chambers formed by n radial baffles (in the absence of baffles, k = j);

[0073]

[0074] Where l is the number of nodes or crests of the wave moving along the axis of the rotating fluid, and L is the distance between the two ends of the chamber. l Represents the distance between two nodes. Fig. 9 Schematic diagram of a rotor chamber partially filled with fluid without a baffle (left) and with a baffle (right) in the case of self-excitation of a first-order radial circular wave (j=1).

[0075] The Navier-Stokes and continuity equations that determine the natural motion of the fluid, which rotate with the rotor cylindrical coordinate system rθz, do not consider the effects of body and surface forces and take the following form:

[0076]

[0077]

[0078] Where u, v and w are the velocities of the fluid particles relative to the rotor, p is the pressure in the fluid, ρ is its density and ω is the rotational speed.

[0079] The boundary conditions are supplemented as follows:

[0080]

[0081] That is, it specifies how these equations behave on the surface of the fluid.

[0082] When r = R, u = 0 (on the outer wall of the cavity); when θ = mγ, w = 0, where m is an integer from 0 to n, γ = 2π / n (on the n partition); when z = 0 or z = L, w = 0 (on the end surface); When r = r, p = 0 (at the free surface of the fluid);

[0083] In a fluid, the disturbance velocities u, v, w are coupled to the disturbance pressure p, which is complementary to the static velocity p0 connected to the angular velocity ω. Similar to the hydrostatic pressure of a fluid column, in a given system, the acceleration is equal to ω 2 (r+r) / 2, the height is equal to rr. So in general, the pressure in the fluid is:

[0084] p=p0+p(r,θ,z,t),p0=ρω 2 (-r 2 ) / 2

[0085] Likewise, the free surface of the fluid can be determined:

[0086] R=r+e(θ,z,t)

[0087] Where e is the disturbance displacement.

[0088] If the perturbation method is used, when each variable is represented in the form of a row according to the small deflection e of the rotor axis, then

[0089] p=p0+εp1+ε 2 p2+…

[0090] u=εu1+ε 2 u2+…,v=εv1+ε 2 v2+…,w=0#(2)

[0091] Since, in a first approximation, the viscosity and the second- and higher-order terms are deleted before and after substituting equation (2) into equation (1), we obtain the following equation:

[0092]

[0093]

[0094] By expressing R = r + e(θ, z, t) without considering the quadratic advantage, the following kinematic and dynamic boundary conditions of the chamber sidewalls and the fluid free surface are satisfied. Next, we look for periodic solutions for u1, ν1, and p1:

[0095] u_1=0,r=R

[0096]

[0097] If we use the generally accepted solution method for wave problems in fluid dynamics, then

[0098] e1(θ,t)=expi(kθ-Ω k t)

[0099] u1(r,θ,t)=U(r)expi(kθ-Ω k t)

[0100] v1(r,θ,t)=V(r)expi(kθ-Ω k t)#(5)

[0101] p1(r,θ,t)=P(r)expi(kθ-Ω k t)

[0102] Among them, Ω k is the angular velocity of the radial-circumferential wave along the entire free surface of the fluid (2πr).

[0103] By substituting into equation (5) and dividing by the universal function expi(kθ-Ω k t), equation (3) can be simplified to the following form:

[0104] -iΩ_k U-2ωV=-1 / ρdP / dr

[0105]

[0106] r dU / dr+U+ikV=0

[0107] The solutions to the first two equations are:

[0108]

[0109] Substituting these relations into the third equation (continuity), we obtain the simplest form of the Bessel equation:

[0110] r 2 P″+rP′-k 2 P=0

[0111] Use general solutions

[0112] P(r)=C1rk +C2r -k #(7)

[0113] where C1 and C2 are determined by the boundary conditions (4) or as a result of the alternative form of equation (5)

[0114] U(R)=0,U(r)=-iΩ k ,P(r)=-ρω 2 r

[0115] Therefore, to determine C1 and C2, simply return to the relationship obtained for U and substitute P and P′

[0116]

[0117] Starting from the condition U(R) = 0

[0118]

[0119] From U(r)=-iΩ k Taking this factor into account (8)

[0120]

[0121] Expression C1r k +C2r -k =-ρω 2 Since equations (8) and (9) give the frequency equation for a radial circular (two-dimensional) surface wave

[0122]

[0123] In the general case (when w ≠ 0), an axial circular (three-dimensional) surface wave occurs. The value of the cyclic characteristic frequency of a two-dimensional surface wave is (in a rotating reference frame)

[0124]

[0125] Therefore, the real number solutions from equations (2) and (5)-(9) are as follows:

[0126]

[0127] Therefore, the velocity on the free surface of the fluid and the pressure on the rotor wall are equal:

[0128]

[0129] Fig.10 Schematic diagram of the cyclic frequency of the basic radial circular surface wave (single node) with no baffle (Ω1), three baffles (Ω3) and six baffles (Ω6), where represents the positive vortex frequency of the fluid, represents the reverse vortex of the fluid. Fig.10 (a) shows the forward and reverse vortex frequencies of different radial fluids; Fig.10 (b) in the figure shows the forward and reverse vortex frequencies of the fluid at different frequencies, and instability occurs at the intersection with the critical instability line.

[0130] Based on the forward and reverse vortex frequencies of the fluid at different frequencies obtained in step S1, the intersection of the forward and reverse vortex frequencies and the critical instability line is regarded as instability, and the theoretical instability interval is obtained. After the rotor instability interval is obtained from the spectrum diagram, it is compared with the theoretical instability interval to determine whether the experimental instability interval is consistent with the calculated instability interval, so as to achieve mutual verification between theory and practice.

[0131] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. An experimental device for studying the high-speed instability range of rotor oil, characterized in that: The experimental device includes a frame, a rotating shaft, an oil tank, a first bearing, a second bearing, a storage plate, a plurality of partitions and a processor; The frame is composed of four square columns and a top plate and a bottom plate parallel to each other; the storage plate is installed in the middle of the frame; the first bearing and the second bearing are installed on the storage plate and the top plate of the frame through the first bearing seat and the second bearing seat respectively; A circular hole is provided between the top plate and the storage plate, and the first bearing and the second bearing are respectively installed in the circular holes of the storage plate and the top plate of the frame through the first bearing seat and the second bearing seat; the rotating shaft vertically passes through the first bearing and the second bearing from top to bottom, and is connected to the oil tank located between the storage plate and the bottom plate, and carries the oil tank to rotate horizontally under the action of the motor; The plurality of partitions are detachably and evenly distributed in the oil tank, one end of the partition is connected to a column located in the center of the oil tank, and the other end is connected to the inner side of the oil tank, so as to evenly divide the oil tank into a plurality of sub-areas; water or oil is poured into the oil tank; For the two oil tank states of no baffle installed in the oil tank and different numbers of baffles installed in the oil tank, the processor controls the motor to drive the shaft to rotate and gradually increase the shaft speed from 0 to a stable state, so that the oil in the oil tank vibrates violently, records the rotor speed in the stable state, and drives the displacement sensor and vibration sensor fixed on the shaft to record the displacement parameters and vibration parameters of the shaft in real time during the speed increase, and drives the high-speed camera to take a vibration image of the oil in the oil tank in real time; the processor performs time domain analysis on the displacement parameters and vibration parameters to generate a vibration state waveform diagram, obtains the corresponding spectrum diagram through Fourier transform, analyzes the spectrum diagram, and obtains frequency components and harmonic components related to the vibration signal. If the rotor displacement increases sharply, it is considered that the rotor system is unstable; combined with the rotor speed in the stable state and the vibration image of the oil, the rotor stability and the oil vibration law are analyzed. If the oil image undergoes a modal transition, it is considered that the rotor is unstable, and then the rotor oil high speed instability range is obtained.

2. The experimental device for studying the high-speed instability range of rotor oil according to claim 1 is characterized in that: The storage plate is installed in the middle of the frame through a stabilizing member; the stabilizing member is a rectangular steel plate with a square hole in the middle. The size of the stabilizing member is consistent with the outer size of the frame, and there are screw holes on the side corresponding to the side screw holes of the square columns of the frame.

3. The experimental device for studying the high-speed instability range of rotor oil according to claim 1 is characterized in that: A circular hole with a diameter of 20 mm is provided between the top plate and the storage plate.

4. The experimental device for studying the high-speed instability range of rotor oil according to claim 1 is characterized in that: The rotating shaft is a cylindrical steel column with a thread at one end; The oil tank is provided with an oil tank top cover, the inner diameter of the oil tank top cover is consistent with the outer diameter of the oil tank, and a screw hole corresponding to the rotating shaft thread is arranged at the center of the oil tank top cover.

5. The experimental device for studying the high-speed instability range of rotor oil according to claim 1 is characterized in that: The oil tank adopts a transparent disc with a central groove. A column is fixed to the bottom of the oil tank in the center of the oil tank. The bottom of the column is cylindrical, and the upper end of the column is a square column. The diagonal length of the square column is less than the diameter of the cylinder.

6. The experimental device for studying the high-speed instability range of rotor oil according to claim 1 is characterized in that: Three partitions or six partitions are evenly installed in the oil tank.

7. An experimental method for studying the high speed instability range of rotor oil based on the experimental device described in any one of claims 1 to 6, characterized in that: The experimental method comprises the following steps: S1: Establish rotor oil accumulation fault model based on NS equation; S2: Keep the oil tank still and pour water or oil into the oil tank without partition; S3: The motor drives the rotor to rotate, increasing its speed from 0 to a preset stable state, recording the parameters of the rotor and oil during the increase, recording the rotor speed in the stable state, and turning off the motor; S4: Based on the rotor speed in the stable state and the rotor oil accumulation fault model, the rotor stability is analyzed and the oil vibration parameters are recorded; S5: repeating steps S2 to S4, if the analysis results of the vibration law of the rotor oil are the same twice, proceeding to step S6; otherwise, repeating steps S2 to S4 until the analysis result of the vibration law of the rotor oil is the same as that of step S4; S6, adding multiple baffles to the oil tank, executing steps S3 to S4, analyzing and obtaining the vibration law of the oil under different baffle conditions, and obtaining the high-speed instability range of the rotor oil.

8. The experimental method for studying the high speed instability range of rotor oil according to claim 7 is characterized in that: Step S1 further comprises the following steps: List the frequency equation for a radial circular surface wave: When w≠0, an axial circular surface wave appears; the value of the cyclic characteristic frequency of the two-dimensional surface wave is: in represents the positive vortex frequency of the fluid, Represents the reverse vortex frequency of the fluid.

9. The experimental method for studying the high speed instability range of rotor oil according to claim 8 is characterized in that: The experimental method also includes the following steps: Based on the forward and reverse vortex frequencies of the fluid at different frequencies obtained in step S1, the intersection of the forward and reverse vortex frequencies and the critical instability line is regarded as instability, and a theoretical instability interval is obtained; The rotor instability interval obtained from the frequency spectrum in step S6 is compared with the theoretical instability interval to determine whether the experimental instability interval is consistent with the calculated instability interval.

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