Unbalance amount position detection method based on diaphragm coupling rotor system

Abstract

The invention relates to an unbalance amount position detection method based on a membrane disc coupling rotor system, and belongs to the technical field of dynamic unbalance amount measurement of rotor systems. The method comprises the following steps: firstly, according to structural parameters of a rotor system, establishing a geometric model of a rotor mechanical system by utilizing three-dimensional CAD software, then establishing a dynamic model of the rotor system by combining Ansys and Adams, setting a rotor parallel misalignment fault, respectively adding unbalanced mass to different phases of a rigid disc of the rotor system, and finally, performing simulation by utilizing the dynamic model. Verification is carried out on a flexible coupler rotor system and a typical single-disc rotor system, only two vibration displacement sensors need to be installed, other additional detection equipment is not needed, use is flexible, and the method has the advantages of being low in cost, high in reliability and capable of achieving nondestructive detection.

Description

Technical Field

[0001] The invention relates to an unbalance position detection method based on a diaphragm disc coupling rotor system, belonging to the technical field of dynamic unbalance measurement of rotor systems. Background Art

[0002] Diaphragm couplings are widely used in daily life and are the core components of rotating machinery. They are widely used in high-precision mechanical equipment such as aviation and ships. They move at high speed during work and are connected to flanges or rotating shafts. When there is an imbalance, the diaphragm coupling will be subjected to centrifugal force and moment of inertia during rotation. If the geometric center and the mass center are not in the same line or even have a large deviation, it will cause vibration and noise of the engine, aggravate the wear of the diaphragm coupling, reduce the service life of the engine, and make it difficult to monitor misalignment faults due to excessive dynamic imbalance caused by the imbalance.

[0003] Misalignment faults can be divided into parallel misalignment and angular misalignment. 60% of mechanical faults are caused by misalignment faults. Diaphragm coupling is a power device that transmits torque with flexible elements. It compensates for misalignment, axial offset and angular offset of the input and output ends through the elastic deformation of the diaphragm. Diaphragm coupling is suitable for rotor systems with large misalignment. This kind of phenomenon has great safety hazards in engineering. Domestic and foreign scholars have conducted a lot of research on the unbalanced position detection and misalignment faults of diaphragm couplings. Real-time monitoring of the operating status of the rotor system, timely feedback of the operating status, early detection of unbalanced position and misalignment faults, and full guarantee of the normal operation of the diaphragm coupling rotor system and the safety of the operating environment can reduce the incidence of safety accidents.

[0004] Most of the literature uses special equipment to monitor the unbalance position, but no research has been proposed to link the relationship between the parallel misalignment direction and the initial position of the unbalance. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a method for detecting the position of the unbalanced amount based on the rotor system of the diaphragm coupling, which can realize online dynamic balancing detection for rotating equipment such as large rotors that are difficult to disassemble and assemble. The method first uses three-dimensional CAD software to establish a geometric model of the rotor mechanical system according to the structural parameters of the rotor system, and then jointly establishes the dynamic model of the rotor system through Ansys and Adams, sets the rotor parallel misalignment fault, adds unbalanced masses to different phases of the rigid disk of the rotor system, and uses the dynamic model simulation to obtain the vibration displacement on the rigid disk of the rotor system under the exciting force of unbalanced masses in different phases, and uses its time domain curve to draw the axis trajectory of the rigid disk. The axis trajectory will appear in a "heart" shape. As the phase of the unbalanced amount changes, the opening direction of the "heart" shape of the axis trajectory will follow the phase where the unbalanced mass is located. The same phase angle changes occur, and the angle relationship between the opening direction of the "heart" shape and the phase of the unbalanced amount can be determined through the simulation results. During the online detection of the rotor equipment, it is necessary to adjust the rotor system to a certain amount of parallel misalignment. At the same time, mark the turntable to be tested before starting, record the initial position of the turntable when the rotor starts, obtain the radial vibration displacement curve through two displacement sensors in mutually perpendicular directions, draw the axis trajectory, and determine the opening angle of the axis trajectory; after the rotor stops, the specific direction of the unbalanced amount can be obtained according to the mark before starting, the opening direction of the axis trajectory, and the opening direction and the angle of the unbalanced mass obtained by simulation analysis. This method has been verified on a flexible coupling rotor system and a typical single-disc rotor system, and has good applicability. The present invention only needs to install two vibration displacement sensors, and does not require other additional detection equipment. The method is flexible to use and has the advantages of low cost, high reliability, and non-destructive testing.

[0006] The technical solution of the present invention is: a method for detecting the unbalance position of a rotor system based on a diaphragm coupling, comprising:

[0007] Construct the mechanical model of the diaphragm coupling rotor system;

[0008] A simplified simulation model of the mechanical model of the diaphragm disc coupling rotor system is jointly established by using Ansys and Adams;

[0009] Simulate the simplified simulation model, set the parallel misalignment fault of the diaphragm coupling, and extract the vibration time domain signal;

[0010] Processing the vibration time domain signal to obtain a shaft center trajectory without imbalance;

[0011] In the simplified simulation model, unbalance is added to different phases of the rigid disk on one side of the diaphragm disk coupling, the initial position of the unbalance is calibrated, the vibration displacement on the rigid disk is extracted, and signal processing is performed to obtain the axis trajectory of the rigid disk under different phases and unbalance excitation forces;

[0012] The axis center trajectory without imbalance and the axis center trajectory of the rigid disk are analyzed, and the imbalance added at different phases and the simulation results are combined to obtain the imbalance position.

[0013] The construction of the mechanical model of the diaphragm disc coupling rotor system includes:

[0014] Solidworks modeling was performed based on the actual model of the diaphragm coupling rotor system. The model was simplified and key moving parts were retained, including the rotor motor system, the diaphragm coupling, and the base adjustment device. The diaphragm coupling included a fixed flange, a gasket, a diaphragm, an intermediate shaft, a rigid disc, and a diaphragm bolt hole. The base adjustment device could adjust the parallel misalignment of the rotor system along the y direction.

[0015] The simplified simulation model of the mechanical model of the diaphragm disc coupling rotor system established by jointly using Ansys and Adams includes:

[0016] Based on SolidWorks, a simulation model is built for the mechanical model of the diaphragm disc coupling rotor system, and the simulation model is simplified, wherein the simplified simulation model includes a bearing, a rotating shaft, a diaphragm disc coupling, and a rotating shaft;

[0017] The simplified simulation model is imported into Ansys for flexible processing, wherein the flexible processing includes a diaphragm disk, a rigid disk, and a connecting shaft.

[0018] Specifically, Ansys APDL makes the diaphragm coupling flexible, and Adams adds drives, constraints, and kinematic pairs to the moving parts and sets the motion parameters;

[0019] The setting of the parallel misalignment fault of the diaphragm coupling and the extraction of the vibration time domain signal include:

[0020] Based on Adams simulation, the rotating shaft of the diaphragm coupling is offset by 0.02mm in the y-axis direction to achieve parallel misalignment in the y-axis direction; the vibration time domain signal is extracted from the position of the center of mass of the diaphragm of the diaphragm coupling, and according to the structural form of the diaphragm coupling, reasonable measuring points, measurement duration, and measurement steps are selected to extract the vibration time domain signals in the x-direction and y-direction respectively. The extracted vibration time domain signal is imported into Origin and the time domain curve is drawn.

[0021] The signal processing of the vibration time domain signal to obtain the axis trajectory without imbalance includes:

[0022] Extract the vibration time domain signal at the position of the center of mass of the diaphragm of the diaphragm coupling, extract the amplitude of the vibration time domain signal in the x and y directions, set the amplitudes in the two directions as the values ​​of the x and y axes, draw the axis trajectory, and a "heart" shape appears.

[0023] The unbalance amount added to different phases of the rigid disk on one side of the diaphragm disk coupling includes:

[0024] Treat the diaphragm coupling in advance and mark the position where the unbalance amount is increased on one end of the diaphragm coupling. The increase position is on the circumference of one end.

[0025] The step of analyzing the axis trajectory without imbalance and the axis trajectory of the rigid disk, combining the imbalance added at different phases and the simulation results to obtain the position of the imbalance includes:

[0026] Changing the phase of the unbalanced amount to obtain a "heart"-shaped opening direction of the rigid disk axis trajectory that changes at the same phase angle as the phase of the unbalanced amount;

[0027] Determine the angle relationship between the "heart"-shaped opening direction and the phase of the unbalance through simulation results;

[0028] According to the simulation guidance experiment, the position of the unbalanced volume is obtained.

[0029] The angle relationship between the "heart"-shaped opening direction and the unbalance phase is determined by simulation results as follows:

[0030] According to the circumferential distribution of bolt holes on the diaphragm disk, unbalanced amounts are added at positions 1, 2, 3, and 4 in turn, and the relationships between the initial positions of the unbalanced amounts and the opening directions of the axis trajectory in the four cases are drawn respectively. The mapping relationship between the “heart”-shaped opening direction and the initial position of the unbalanced amount is established, and the angular relationship between the “heart”-shaped opening direction and the phase of the unbalanced amount is obtained.

[0031] Specifically, three different rotation speeds were set to verify whether the rotation speed had an effect on the angle relationship;

[0032] According to the simulation guidance experiment, the unbalance position is obtained as follows:

[0033] During the online detection of the rotor equipment, the parallel misalignment of the rotor system is adjusted. At the same time, before starting, a mark is made on the turntable to record the initial position of the turntable when the rotor starts;

[0034] The radial vibration displacement curve is obtained by two displacement sensors in mutually perpendicular directions, and the axis trajectory is drawn to determine the axis trajectory opening angle;

[0035] After the rotor stops, the position of the unbalance is obtained based on the mark before startup and the opening direction of the axis trajectory, as well as the angle relationship between the "heart"-shaped opening direction and the phase of the unbalance obtained by simulation.

[0036] The beneficial effects of the present invention are: the present invention establishes a solidworks mechanical model of the diaphragm disc coupling rotor system based on the existing coupling rotor system, and uses Ansys and Adams to jointly establish a simulation model of the rotor system, thereby optimizing the traditional method of detecting the position of the imbalance, and does not require additional detection instruments or the disadvantage of limited installation space for the detection instruments. This method has the advantages of low cost, high reliability, and non-destructive testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a flow chart of the steps of the present invention;

[0038] Figure 2 It is a schematic diagram of a rotor model of a diaphragm disc coupling to be tested known in the present invention;

[0039] Figure 3 It is a schematic diagram of the diaphragm coupling and the position of the unbalanced mass of the present invention;

[0040] Figure 4 A schematic diagram of the coordinate system where the diaphragm coupling of the present invention is located and a schematic diagram of the position where the unbalance amount is added;

[0041] Figure 5 Add a schematic diagram of the bolt holes where the unbalance is located;

[0042] Figure 6 This is a simplified schematic diagram for the simulation of a diaphragm coupling;

[0043] Figure 7 It is the time domain curve diagram under parallel misalignment fault;

[0044] Figure 8 This is the axis trajectory diagram when the unbalanced mass is at position 1 under parallel misalignment fault;

[0045] Fig. 9 This is the axis trajectory diagram of the unbalanced mass at position 2 under parallel misalignment fault;

[0046] Fig.10 This is the axis trajectory diagram of the unbalanced mass at position 3 under parallel misalignment fault;

[0047] Fig.11 This is the axis trajectory diagram of the unbalanced mass at position 4 under parallel misalignment fault;

[0048] Fig.12 It is the axis trajectory diagram of parallel misalignment fault and unbalanced mass at position 1 at different speeds;

[0049] Fig.13 Another rotor system model diagram for re-verification of the method of the present invention;

[0050] Fig.14It is a mapping diagram of the axis trajectory opening direction-unbalance position of the rotor system. DETAILED DESCRIPTION

[0051] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0052] Embodiment 1, as Figure 1 As shown, a method for detecting the unbalance position of a rotor system based on a diaphragm coupling comprises:

[0053] Construct the mechanical model of the diaphragm coupling rotor system;

[0054] A simplified simulation model of the mechanical model of the diaphragm disc coupling rotor system is jointly established by using Ansys and Adams;

[0055] Simulate the simplified simulation model, set the parallel misalignment fault of the diaphragm coupling, and extract the vibration time domain signal;

[0056] Processing the vibration time domain signal to obtain a shaft center trajectory without imbalance;

[0057] In the simplified simulation model, unbalance is added to different phases of the rigid disk on one side of the diaphragm disk coupling, the initial position of the unbalance is calibrated, the vibration displacement on the rigid disk is extracted, and signal processing is performed to obtain the axis trajectory of the rigid disk under different phases and unbalance excitation forces;

[0058] Analyze the axis center trajectory without imbalance and the axis center trajectory of the rigid disk, and obtain the imbalance position by combining the imbalance added at different phases and the simulation results;

[0059] Set different speeds to verify whether the speed affects the angle relationship;

[0060] Verify another typical rotor mechanical structure to increase the universality of this method;

[0061] like Figure 2 As shown, the diaphragm coupling rotor system includes a rotor motor system 1, a diaphragm coupling 2, and a base adjustment device 3. The base adjustment device 3 can adjust the parallel misalignment of the rotor system along the y direction. The diaphragm coupling 2 is used as an intermediate connecting component to connect the rotor motor system 1 and the base adjustment device 3, which are connected together to form a shaft system to transmit motion and torque. After setting the parallel misalignment along the y axis, the misalignment is added to the diaphragm coupling 2.

[0062] like Figure 3 As shown, it is an enlarged view of the diaphragm coupling 2, including a fixed flange 1, a gasket 2, a diaphragm 3, an intermediate shaft 4, a rigid disc 6, and a diaphragm bolt hole 5; the diaphragm bolt hole is marked, and an unbalanced mass is added at this position; Figure 4 As shown, the position is added for the unbalanced amount;

[0063] like Figure 5 As shown, the distribution position of the bolt holes of the diaphragm disk is shown, where four bolt holes are marked and numbered 1, 2, 3, and 4. The axes of the bolt holes 1 and 3 are parallel to the y-axis, and the axes of the bolt holes 2 and 4 are parallel to the x-axis. Unbalanced masses will be added at these four positions later.

[0064] The simplified simulation model of the mechanical model of the diaphragm disc coupling rotor system established by jointly using Ansys and Adams includes:

[0065] Based on solidworks, the rotor model of the diaphragm coupling is modeled and simplified. The simplified model is as follows Figure 6 As shown, it includes bearing 1, shaft 2, diaphragm coupling 3, and shaft 4. The format is saved as parasolid and imported into Adams. Diaphragm coupling 3 is imported into Ansys for flexible processing. Its flexible body part includes diaphragm, rigid disc, and connecting shaft. The model is simulated in Adams, and fixed joint, rotating joint, and drive are added.

[0066] The parallel misalignment fault of the diaphragm coupling is set, including:

[0067] Based on Adams simulation, the rotating shaft of the diaphragm coupling is offset by 0.02mm in the y-axis direction, which has achieved parallel misalignment in the y-axis direction;

[0068] The extracting of the vibration time domain signal comprises:

[0069] Extract the vibration time domain signal at the location of the centroid of the diaphragm of the diaphragm coupling, extract the vibration time domain signals in the x direction and y direction respectively, import the extracted vibration time domain signal into Origin, and draw the time domain curve. The time domain curve is as follows Figure 7 shown.

[0070] The signal processing of the vibration time domain signal to obtain the axis trajectory without imbalance includes:

[0071] After extracting the vibration time domain signal at the location of the centroid of the diaphragm coupling, extract the amplitude of the vibration time domain signal in the x and y directions, set the amplitudes in the two directions as the values ​​of the x and y axes, and draw the axis trajectory. The axis trajectory is as follows: Figure 8 As shown, an “inner 8” shape appears, indicating that the parallel misalignment setting is correct.

[0072] The adding of unbalanced amounts at different phases of the rigid disk on one side of the diaphragm disk coupling in the simplified simulation model includes:

[0073] According to the bolt holes distributed on the circumference of the diaphragm, Figure 5 As shown, first increase the unbalance of 2g at position 1, and the initial position of the unbalance and the opening direction of the axis trajectory are as follows Figure 8 As shown. When the unbalance of 2g is increased at position 2, the initial position of the unbalance and the opening direction of the axis trajectory are as follows Fig. 9 As shown, 2g of unbalance is added at position 3, and the initial position of the unbalance and the opening direction of the axis trajectory are as follows Fig.10 As shown, 2g of unbalance is added at position 4, and the initial position of the unbalance and the opening direction of the axis trajectory are as follows Fig.11 shown.

[0074] The setting of different rotation speeds to verify whether the rotation speed has an effect on the angle relationship includes:

[0075] According to the mapping relationship between the "heart" opening direction and the initial position of the imbalance when the imbalance is at position 1, three different speeds are set, namely 3000r / min, 6000r / min, and 9000r / min, respectively, to verify that the mapping relationship has nothing to do with the speed, such as Fig.12 shown.

[0076] The verification of another typical rotor mechanical structure to increase the universality of the method includes:

[0077] According to the above method, another typical rotor system is verified again to increase the universality of the method, which has been applicable to both the diaphragm coupling system and the rotor system. The rotor system model diagram that is verified again is as follows: Fig.13 As shown, it includes motor 1, diaphragm coupling 2, bearing seats 3 and 6, shaft 4, and disc 5. The unbalanced mass is added to disc 5, and the initial phase angle increases successively. The axis trajectory opening direction-unbalance position mapping diagram of the rotor system is shown in Fig.14 shown.

[0078] Through the above discussion on the unbalanced position and the axis trajectory opening direction, a mapping relationship between the "heart" shaped opening direction and the initial position of the unbalanced amount is established, and finally a position mapping relationship between the unbalanced amount uncertain position and the axis trajectory opening direction is obtained.

[0079] The specific implementation modes of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A method for detecting the unbalance position of a rotor system based on a diaphragm coupling, characterized in that: The method includes: Construct the mechanical model of the diaphragm coupling rotor system; A simplified simulation model of the mechanical model of the diaphragm disc coupling rotor system is jointly established by using Ansys and Adams; Simulate the simplified simulation model, set the parallel misalignment fault of the diaphragm coupling, and extract the vibration time domain signal; Processing the vibration time domain signal to obtain a shaft center trajectory without imbalance; In the simplified simulation model, unbalance is added to different phases of the rigid disk on one side of the diaphragm disk coupling, the initial position of the unbalance is calibrated, the vibration displacement on the rigid disk is extracted, and signal processing is performed to obtain the axis trajectory of the rigid disk under different phases and unbalance excitation forces; The axis center trajectory without imbalance and the axis center trajectory of the rigid disk are analyzed, and the imbalance added at different phases and the simulation results are combined to obtain the imbalance position.

2. The unbalance position detection method based on the diaphragm coupling rotor system according to claim 1 is characterized in that: The construction of the mechanical model of the diaphragm disc coupling rotor system includes: A rotor motor system, a diaphragm coupling, and a base adjustment device. The diaphragm coupling includes a fixed flange, a gasket, a diaphragm, an intermediate shaft, a rigid disc, and a diaphragm bolt hole. The base adjustment device can adjust the parallel misalignment of the rotor system along the y direction.

3. The method for detecting the unbalance position of a rotor system based on a diaphragm coupling according to claim 1, characterized in that: The simplified simulation model of the mechanical model of the diaphragm disc coupling rotor system established by jointly using Ansys and Adams includes: Based on SolidWorks, a simulation model is built for the mechanical model of the diaphragm disc coupling rotor system, and the simulation model is simplified, wherein the simplified simulation model includes a bearing, a rotating shaft, a diaphragm disc coupling, and a rotating shaft; The simplified simulation model is imported into Ansys for flexible processing, wherein the flexible processing includes a diaphragm disk, a rigid disk, and a connecting shaft.

4. The method for detecting the unbalance position of a rotor system based on a diaphragm coupling according to claim 1, characterized in that: The setting of the parallel misalignment fault of the diaphragm coupling and the extraction of the vibration time domain signal include: Based on Adams simulation, the rotating shaft of the diaphragm coupling is offset by 0.02mm in the y-axis direction to achieve parallel misalignment in the y-axis direction; the vibration time domain signal is extracted at the position of the center of mass of the diaphragm of the diaphragm coupling, and the vibration time domain signals in the x-direction and y-direction are extracted respectively. The extracted vibration time domain signal is imported into Origin to draw the time domain curve.

5. The method for detecting the unbalance position of a rotor system based on a diaphragm coupling according to claim 1, characterized in that: The signal processing of the vibration time domain signal to obtain the axis trajectory without imbalance includes: Extract the vibration time domain signal at the position of the centroid of the diaphragm of the diaphragm coupling, extract the amplitude of the vibration time domain signal in the x and y directions, set the amplitudes in the two directions as the values ​​of the x and y axes, draw the axis trajectory, and a "heart" shape appears.

6. The method for detecting the unbalance position of a rotor system based on a diaphragm coupling according to claim 1, characterized in that: The step of analyzing the axis trajectory without imbalance and the axis trajectory of the rigid disk, combining the imbalance added at different phases and the simulation results to obtain the position of the imbalance includes: Changing the phase of the unbalanced amount to obtain a "heart"-shaped opening direction of the rigid disk axis trajectory that changes at the same phase angle as the phase of the unbalanced amount; Determine the angle relationship between the "heart"-shaped opening direction and the phase of the unbalance through simulation results; According to the simulation guidance experiment, the position of the unbalanced volume is obtained.

7. The method for detecting the unbalance position of a rotor system based on a diaphragm coupling according to claim 6, characterized in that: The angle relationship between the "heart"-shaped opening direction and the phase of the unbalance amount determined by the simulation results is specifically: According to the circumferential distribution of bolt holes on the diaphragm disk, unbalanced amounts are added at positions 1, 2, 3, and 4 in turn. The relationships between the initial positions of the unbalanced amounts and the opening directions of the axis trajectory in the four cases are plotted respectively. The mapping relationship between the "heart"-shaped opening direction and the initial position of the unbalanced amount is established, and the angular relationship between the "heart"-shaped opening direction and the phase of the unbalanced amount is obtained.

8. The method for detecting the unbalance position of a rotor system based on a diaphragm coupling according to claim 6, characterized in that: According to the simulation guidance experiment, the unbalance position is obtained as follows: During the online detection of the rotor equipment, the parallel misalignment of the rotor system is adjusted. At the same time, before starting, a mark is made on the turntable to record the initial position of the turntable when the rotor starts; The radial vibration displacement curve is obtained by two displacement sensors in mutually perpendicular directions, and the axis trajectory is drawn to determine the axis trajectory opening angle; After the rotor stops, the position of the unbalance is obtained based on the mark before startup and the opening direction of the axis trajectory, as well as the angle relationship between the "heart"-shaped opening direction and the phase of the unbalance obtained by simulation.

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