A high-precision vibration simulation experiment device for a propeller-shaft-hull coupling system

Abstract

The application is a kind of high-precision vibration simulation experiment device of propeller-shaft-hull coupling system, belonging to the field of marine engineering vibration simulation technology; including test structure module, quick dismounting tool module, signal input module, signal acquisition and processing module; the test structure module includes a shell, a motor coaxially installed in the shell, a counterweight, a propulsion shaft system and an eccentric block, and a propeller is installed on the output end of the propulsion shaft system; the quick dismounting tool module suspends and hoists the test structure module in a flexible connection mode, to simulate the boundaryless constraint of underwater vehicles under actual working conditions; the signal input module is used to send instructions to the driving components of the test structure module; the signal acquisition and processing module includes a sensor and an upper computer. The application solves the problems that the prior art is difficult to accurately simulate the constraint conditions and excitations in the fluid, and the fixed constraint method has high error.

Description

Technical Field

[0001] The invention belongs to the technical field of marine engineering vibration simulation, and in particular relates to a high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system. Background Art

[0002] Underwater vehicles, with their robust stealth and sudden attack capabilities, play an indispensable role in national defense. Good stealth not only ensures the ability of underwater vehicles to launch sudden attacks but also serves as the key to their survival. Research has shown that for every 5-decibel increase in the radiated noise of such systems, the enemy's warning distance increases by 50% and the effective hit rate decreases by 25%. An underwater vehicle is essentially an internal high-speed rotating power system. Based on the source and transmission path of its vibration noise, it can be simplified into a propeller-shaft-housing coupling structure. Vibration radiated noise primarily originates from the internal engine. The engine's output torque drives the propeller through the propulsion shaft system, causing sudden changes in the external flow field and generating flow noise. Another component primarily originates from the vibration of the propeller and engine, which is transmitted to the housing through the connection structure, thereby driving the fluid medium around the outer surface and causing radiated noise.

[0003] Conducting experimental vibration analysis of propeller-shaft-shell coupling models is a crucial tool for optimizing structural parameters, evaluating device performance, and reducing vibration and noise. Deepwater experiments can realistically simulate the system's actual operating conditions and environment. However, deepwater basins present unique environmental conditions with numerous uncertainties and significant risks. Acquiring sensor data each time requires significant manpower and costs. Currently, vibration and noise analysis of such systems focuses on theoretical and numerical simulations.

[0004] Building a simulated experimental setup on land instead of conducting experiments in water offers a new solution. However, it is difficult to accurately simulate the constraints and excitations in the fluid. Fixed constraint methods suffer from high errors, and the use of theoretical models and numerical solution feedback guidance has become an urgent need for the design of an onshore vibration simulation test bench for the propeller-shaft-shell coupling system. To this end, starting from theoretical layout and three-dimensional design, we provide a high-precision vibration simulation test system and method for the propeller-shaft-shell coupling system to address these issues and achieve accurate vibration simulation of underwater vehicles on land. Summary of the Invention

[0005] Technical issues to be solved:

[0006] In order to avoid the shortcomings of the existing technology, the present invention provides a high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system, which connects the propeller-shaft-shell as an integral unit and adopts a hoisting form for positioning to simulate the real working conditions of the underwater vehicle, and optimizes the counterweight block and the eccentric block to solve the problems that the existing technology is difficult to accurately simulate its constraints and excitations in the fluid, and the fixed constraint method has high errors.

[0007] The technical solution of the present invention is: a high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system, comprising a test structure module, a quick disassembly tooling module, a signal input module, and a signal acquisition and processing module;

[0008] The test structure module includes a housing and a motor, a counterweight, a propulsion shaft system, and an eccentric block coaxially mounted therein. A propeller is coaxially mounted at the output end of the propulsion shaft system to simulate a physical underwater vehicle. The propeller is placed in a water tank to simulate the propeller's underwater working state.

[0009] The quick-disassembly tooling module suspends and hoists the test structure module in a flexible connection manner to simulate the unbounded constraints of the underwater vehicle under actual working conditions;

[0010] The signal input module is used to send instructions to the driving components of the test structure module to adjust the propeller speed and the water level in the water tank to simulate external excitation under different working conditions;

[0011] The signal acquisition and processing module includes a sensor and a host computer. The sensor sends test data to the host computer through a data collector, and the host computer analyzes and processes the received data to obtain experimental results.

[0012] A further technical solution of the present invention is: a counterweight block is provided on the periphery of the motor, and eccentric blocks are installed at both ends of its rotating shaft. The output end of the rotating shaft is coaxially connected to the input end of the propulsion shaft system, and the deflection amount is controlled by adjusting the overlapping angle of the eccentric blocks at both ends.

[0013] A further technical solution of the present invention is: the method for selecting the counterweight block is:

[0014] Preliminary calculation: Based on the experimental requirements, calculate the total counterweight required for the experimental device to ensure that the system can maintain balance under static and dynamic conditions;

[0015] Select the number of ballast weights: Based on the calculated total ballast weight, select the appropriate number of standard ballast weights to ensure that the final total weight meets the calculated requirements;

[0016] Counterweight installation: Install the selected counterweights on the housing and motor to ensure even weight distribution to maintain the balance of the test structure module.

[0017] A further technical solution of the present invention is: the method for selecting the overlap angle of the eccentric block is to construct a dynamic model of the actual underwater vehicle physical model, obtain the predicted value of the shell vibration acceleration through simulation; then measure the actual value of the shell vibration acceleration through experiments; compare the predicted value of the shell vibration acceleration with the experimental value, and when the two basically coincide, it is judged that the corresponding eccentric angle is a certain deflection angle; the eccentric block is a cylindrical structure with a cross-section that is approximately semicircular.

[0018] A further technical solution of the present invention is: the method for constructing a dynamic model of the actual underwater vehicle physical model is:

[0019] The physical model of the underwater vehicle is simplified to a propeller-shaft-shell double-beam model, where the shell is a hollow beam and the propulsion shaft is a solid beam. The finite element method is used to derive the dynamic differential equation as follows:

[0020] (1)

[0021] in, They represent the total mass matrix, stiffness matrix, damping matrix, and gyroscope matrix of the double-beam system respectively; is the angular velocity of the propulsion shaft system; is the gravity acting on the system; The Hertzian contact force between the propulsion shaft and the housing bearing, i.e., the nonlinear restoring force, is expressed as

[0022] (2)

[0023]

[0024] in, represents the Hertzian contact stiffness coefficient; is the Heaviside function of the bearing, is the radial clearance of the bearing, Indicates the displacement of the center of the bearing inner ring in the radial horizontal and vertical directions. It represents the Hertzian contact force applied in the horizontal radial direction at the center of the inner ring of the bearing. It represents the Hertzian contact force applied in the vertical direction to the center of the inner ring of the bearing; is the rotational eccentric force, expressed as

[0025] (3)

[0026] in, are applied in the radial horizontal and radial vertical directions of the propulsion shaft system respectively;

[0027] The eccentric mass and eccentricity of the propeller-shaft-shell double beam model are based on the actual model of the underwater vehicle rotating body mass. Deviation from assembly Equivalent replacement;

[0028] The system dynamic response is calculated according to formula (1), and the coincidence angle of the eccentric block is found by comparing it with the experimentally measured response signal.

[0029] A further technical solution of the present invention is that both ends of the housing of the motor are coaxially mounted in the housing via flanges.

[0030] A further technical solution of the present invention is: the water tank is provided with a water inlet, a water outlet and a propeller shaft mounting hole, and valves for controlling on and off and adjusting flow are installed at the water inlet and the water outlet. The propeller shaft mounting hole is dynamically sealed to the propeller shaft, which can ensure sealing while selecting rotation.

[0031] A further technical solution of the present invention is: the quick-disassembly tooling module includes an electric cylinder, a flexible rope, a hook and a gantry bracket, and the gantry bracket is installed on the basic platform as a suspension support; two electric cylinders are symmetrically installed on the top crossbeam of the gantry bracket, and their output ends are respectively fixedly connected to the roots of the flexible ropes; the free end of the head of the flexible rope passes through the guide hole on the gantry bracket and is connected to the hook; the hook is installed in cooperation with the lifting ring on the test structure module shell, and the vertical height position of the test structure module can be adjusted by driving the electric cylinder.

[0032] A further technical solution of the present invention is: a method for controlling the external excitation received by the propeller is to adjust the water level in the water tank by adjusting the water inlet and outlet valves of the water tank. The higher the water level, the more propeller blades immersed in the water, and the greater the external excitation received during the rotation process; the lower the water level, the fewer propeller blades immersed in the water, and the smaller the external excitation received during the rotation process.

[0033] A method for testing a high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system, characterized by the following specific steps:

[0034] Step 1: Layout of the experimental device structure; Based on the actual vibration test requirements, build a high-precision vibration simulation test system for the propeller-shaft-shell coupling system;

[0035] Step 2: Parameter design and preparation; determine the number of counterweights required based on the model of the underwater vehicle being simulated; determine the overlap angle of the eccentric blocks based on the eccentricity of the motors of different models; and determine the water volume in the water tank based on the external excitations applied to the propeller at different speeds.

[0036] Step 3: Quickly disassemble the tooling; using the quick disassembly tooling module, install the corresponding counterweights on the motor and the inside of the housing, install the flange to connect the propulsion shaft system and the housing, connect the housings, and adjust the height of the test structure module;

[0037] Step 4: Verify the feasibility of the coupling system and test method. Based on the test results, compare the test target values ​​and evaluate the performance and reliability of the propeller-shaft-shell coupling system in this vibration test system and method.

[0038] Beneficial effects

[0039] The present invention provides a high-precision vibration simulation experimental device for a propeller-shaft-housing coupling system, utilizing a modular design. Each module is independent of the others, facilitating installation and maintenance. The test structure modules within the experimental device can simulate the actual operating conditions of an underwater vehicle, and the selection of counterweights and eccentric blocks ensures a stable experiment and accurate test values.

[0040] This invention facilitates equipment installation and component adjustment through the quick disassembly of tooling modules, significantly improving test efficiency. Secondly, the water tank design allows for the adjustment of water volumes to meet a variety of underwater excitation requirements, flexibly simulating various working conditions.

[0041] The proposed mounting method optimizes the simulation of boundary constraints, while the hoisting constraints realistically reproduce the underwater boundary conditions of the vehicle. The water tank and hoisting design improve the accuracy of underwater vehicle vibration simulation, enabling high-precision simulation of the complex propeller-shaft-housing coupled system.

[0042] The cooperation of various modules improves the overall performance and test accuracy of the system, ensuring the reliability and validity of the test results. Therefore, the present invention has the advantages of accurate verification results, good stability, simple operation, and easy promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The layout of the high-precision vibration simulation test system for the propeller-shaft-shell coupling system of the present invention;

[0044] Figure 2 Schematic cross-sectional view of the experimental device of the present invention;

[0045] Figure 3 It is a schematic structural diagram of the power device of the present invention;

[0046] Figure 4 Schematic diagram of the motor structure of the present invention;

[0047] Figure 5 The system testing method steps of the present invention;

[0048] Figure 6 The eccentric blocks of the invention overlap at an angle of 15°;

[0049] Figure 7 The shell time domain / frequency domain signal of the present invention;

[0050] Explanation of the reference numerals: 11-housing, 12-flange, 13-motor, 14-counterweight, 15-sealing ring, 16-propeller, 17-propulsion shaft system, 18-eccentric block, 19-water tank; 21-electric cylinder, 22-wire rope, 23-lifting ring, 24-gantry bracket, 25-pulley bracket, 26-horizontal guide rail, 27-basic platform; 31-control cabinet, 32-transmission line; 41-acceleration, 42-transmission line, 43-data collector, 44-lower computer. DETAILED DESCRIPTION

[0051] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0052] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0053] Given the difficulties in accurately simulating the constraints and excitations in fluids encountered in existing technologies, as well as the high error associated with fixed constraint methods, the present invention provides a high-precision vibration simulation experimental device for a propeller-shaft-housing coupling system, comprising a test structure module, a quick-detachable fixture module, a signal input module, and a signal acquisition and processing module. The test structure module comprises a housing and a motor, a counterweight, a propulsion shaft system, and an eccentric mass coaxially mounted therein. A propeller is coaxially mounted at the output end of the propulsion shaft system to simulate a physical underwater vehicle. The propeller is placed in a water tank to simulate its underwater operating state. The quick-detachable fixture module suspends the test structure module using a flexible connection to simulate the unbounded constraints of an underwater vehicle under actual operating conditions. The signal input module is configured to send instructions to a drive component of the test structure module to adjust the propeller's speed and the water level in the water tank to simulate external excitations under different operating conditions. The signal acquisition and processing module comprises a sensor and a host computer. The sensor transmits test data to the host computer via a data collector, and the host computer analyzes and processes the received data to obtain experimental results.

[0054] The present invention adjusts the water level in the water tank to meet the external excitation requirements of the underwater vehicle propeller under different actual operating conditions. The test structure module is constrained by flexible rope hoisting, reducing the degrees of freedom in three directions, which is closer to the unbounded constraint method of the underwater vehicle under actual operating conditions.

[0055] The above technical solution is further described below with reference to the accompanying drawings:

[0056] Reference Figure 1-Figure 4 As shown, the present invention provides a high-precision underwater vehicle vibration simulation test bench, namely, a high-precision vibration simulation test device for a propeller-shaft-housing coupling system, comprising 1 a test structure module, 2 a quick-disassembly tooling module, 3 a signal input module, and 4 a signal acquisition and processing module. The test structure module 11 includes a housing 11, which is connected to its interior 13 a motor, 14 a counterweight, 16 a propeller, 17 a propulsion shaft system, and 18 an eccentric block via a flange 12. The quick-disassembly tooling module 2 includes: an electric cylinder 21 connected to a steel wire rope 22 and a lifting ring 23, both mounted on a gantry 24, which is connected to a base platform 27, on which a pulley bracket 25 and a horizontal guide rail 26 are mounted. The signal input module 3 includes: a control cabinet 31 that inputs signals and adjusts the motor 13 speed via a transmission line 32. The signal acquisition and processing module 4 includes: an acceleration sensor 41 fixed to the surface of the housing 11, and the signal is transmitted via a transmission line 42 to a data collector 43, which is then connected to a lower computer 44 for data analysis and processing.

[0057] Furthermore, the housing 11 is divided into seven sections according to the connection conditions. The end of the housing 11 is connected to the water tank 19 via a sealing ring 15 to prevent fluid leakage.

[0058] Preferably, the eccentric force of the propulsion shaft system 16 during rotation is changed by adjusting the overlap angle of the eccentric blocks 17. The water tank 19 can simulate the working conditions of the propeller 16 in a real water basin.

[0059] It is worth noting that the 21 electric cylinder adjusts the length of the extended steel wire rope 22, thereby freely adjusting the upper and lower heights of the 1 test structure module to facilitate installation and disassembly.

[0060] The working principle and use process of the present invention refer to Figure 5 :

[0061] Step 1: Test System Structure Layout. Based on actual vibration test requirements, a high-precision vibration simulation test system for the propeller-shaft-housing coupling system was constructed. This system consisted of: 1. a test structure module; 2. a quick-release tooling module; 3. a signal input module; and 4. a signal acquisition and processing module. Requirements Analysis and System Planning: 1) Clarify Test Requirements: Based on actual vibration test requirements, determine the operating conditions, accuracy requirements, and test scope to be simulated by the test system. 2) System Planning: Identify the four main modules of the system and their interconnections.

[0062] Step 2: Parameter design and preparation.

[0063] 1) Selection of 14 counterweights: To ensure the balance and stability of the 1 test structure module, it is necessary to select an appropriate number of 14 counterweights based on the specific test requirements. The steps for selecting 14 counterweights are as follows: Preliminary calculation: Based on the experimental requirements, calculate the total counterweight weight required by the system. Taking into account the system structure and experimental environment, this total weight should ensure that the system can maintain balance under both static and dynamic conditions; Select the number of 14 counterweights: Based on the calculated total counterweight weight, select an appropriate number from the standard counterweights to ensure that the final total weight meets the calculation requirements; 14 counterweight installation: Install the selected 14 counterweights on the 11 housing and 13 motor to ensure that the weight is evenly distributed to maintain the balance of the 1 test structure module.

[0064] 2) Selection of the overlap angle of the 18 eccentric blocks: The overlap angle of the 18 eccentric blocks directly affects the vibration characteristics of the test structure module. By adjusting the overlap angle, different vibration conditions can be simulated. The steps for selecting the overlap angle of the 18 eccentric blocks are as follows: Construct a dynamic model of the actual underwater vehicle physical model, simulate the shell vibration acceleration, and calculate the overlap angle of the eccentric blocks of the test device based on the acceleration and mass. The underwater vehicle is simplified to a propeller-shaft-shell double beam (Timushenko beam) model, with the shell as a hollow beam and the propulsion shaft system as a solid beam. The finite element method is used to derive the dynamic differential equation as follows:

[0065] (1)

[0066] in, They represent the total mass matrix, stiffness matrix, damping matrix, and gyroscope matrix of the double-beam system respectively. is the angular velocity of the propulsion shaft system. is the gravity acting on the system. The Hertzian contact force between the propulsion shaft and the housing bearing, i.e. the nonlinear restoring force, can be expressed as

[0067] (2)

[0068]

[0069] in, represents the Hertzian contact stiffness coefficient; is the Heaviside function of the bearing, is the radial clearance of the bearing, Indicates the displacement of the center of the bearing inner ring in the radial horizontal and vertical directions. It represents the Hertzian contact force applied in the horizontal radial direction at the center of the inner ring of the bearing. It represents the Hertzian contact force applied in the vertical direction to the center of the inner ring of the bearing; The rotational eccentric force can be written as

[0070] (3)

[0071] in, The eccentric mass and eccentricity of the simulation model can be calculated using the actual model of the underwater vehicle's rotating body mass. Deviation from assembly Equivalent replacement. According to formula (1), the system dynamic response can be calculated, and the overlap angle of the eccentric blocks can be found by comparing with the experimental response signal. The overlap angles of the two sets of approximate semicircular eccentric blocks provided by the present invention are 15° apart. Figure 6 Refer to Table 1 for the corresponding moments of inertia and eccentricity. When the overlap angles are straight, the moments of inertia are the same. Because the x-direction is axial, the overlap angle of the eccentric blocks does not affect the moment of inertia and eccentricity in that direction. Adjust the overlap angle of the two eccentric blocks 18 at each end of the motor 13 as required. Ensure that the eccentric blocks are securely fixed after adjustment to prevent displacement or loosening during vibration.

[0072] 3) Selecting the water level in the 19-meter water tank: The higher the water level, the more of the 16-meter propeller blades will be submerged, and the greater the external excitation during rotation. Adjust the water level to the appropriate height by adjusting the water tank's inlet and outlet valves.

[0073] Step 3: Quickly disassemble the tooling. Relying on the quick-disassembly tooling module, install the corresponding counterweights inside the motor and the housing, install the flange to connect the propulsion shaft system and the housing, connect the housings, and adjust the height of the test structure module. When conducting a vibration test, the use of an electric cylinder can precisely adjust the height of the housing in the vertical direction to meet the height position requirements of different test conditions. A bracket structure with a pulley is provided at the lower end. The pulley bracket allows the housing to rotate freely in the axial direction, which facilitates the removal of the bolts between the various sections of the housing. At the same time, a horizontal guide rail is attached under the pulley bracket to allow the housing to move freely in the axial direction, reducing the workload of manual handling. During the experiment, the height of the test structure module 1 was increased by reducing the extended length of the 21 electric cylinder and shortening the length of the 22 wire rope.

[0074] After the experiment is complete, the position of the pulley bracket 25 is adjusted to ensure it is evenly distributed below the housing 11. The length of the electric cylinder 21 is increased, the length of the wire rope 22 is lengthened, and the test structure module 1 is lowered to land safely on the pulley bracket 25. This allows the test structure module to be adjusted in three degrees of freedom: vertical, axial, and rotational, meeting the requirements of different test conditions.

[0075] Table 1 Attributes of eccentric blocks at different overlap angles

[0076]

[0077] Step 4: Signal input and acquisition. Verify the feasibility of the coupling system and test method. According to the test results, compare the test target values ​​and evaluate the performance and reliability of the propeller-shaft-shell coupling system in the vibration test system and method; Signal input: 31 The control cabinet inputs the 13 motor speed signal, which is transmitted to the 13 motor through the 32 transmission line, thereby adjusting its actual speed; Signal acquisition: 41 The acceleration sensor is pasted to the surface of the shell 11, and the 42 transmission line transmits the measured acceleration electrical signal to the 43 data collector, and the data is analyzed and processed by the 44 lower computer. When the motor speed is 600, 900, and 1200 r / min respectively, the shell dynamic response refers to Figure 7 .

[0078] Table 2 Test results

[0079]

[0080] The corresponding main frequencies in Table 2 are 9.8, 14.8, and 19.8 Hz, respectively, indicating that the coupled system is sufficiently stable, the simulation accuracy is sufficiently high, and the error is small (consistent with a speed of 60 r / min, corresponding to 1 Hz, and an error of 0.2 Hz due to the sampling frequency).

[0081] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention.

Claims

1. A high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system, characterized by: It includes test structure module, quick disassembly tooling module, signal input module, and signal acquisition and processing module; The test structure module includes a housing and a motor, a counterweight, a propulsion shaft system, and an eccentric block coaxially mounted therein. A propeller is coaxially mounted at the output end of the propulsion shaft system to simulate a physical underwater vehicle. The propeller is placed in a water tank to simulate the propeller's underwater working state. The quick-disassembly tooling module suspends and hoists the test structure module in a flexible connection manner to simulate the unbounded constraints of the underwater vehicle under actual working conditions; The signal input module is used to send instructions to the driving components of the test structure module to adjust the propeller speed and the water level in the water tank to simulate external excitation under different working conditions; The signal acquisition and processing module includes a sensor and a host computer. The sensor sends test data to the host computer through a data collector, and the host computer analyzes and processes the received data to obtain experimental results.

2. The high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system according to claim 1, characterized in that: The motor is provided with a counterweight block on the periphery, and eccentric blocks are installed at both ends of its rotating shaft. The output end of the rotating shaft is coaxially connected to the input end of the propulsion shaft system, and the deflection amount is controlled by adjusting the overlapping angle of the eccentric blocks at both ends.

3. The high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system according to claim 1, characterized in that: The method for selecting the counterweight block is: Preliminary calculation: Based on the experimental requirements, calculate the total counterweight required for the experimental device to ensure that the system can maintain balance under static and dynamic conditions; Select the number of ballast weights: Based on the calculated total ballast weight, select the appropriate number of standard ballast weights to ensure that the final total weight meets the calculated requirements; Counterweight installation: Install the selected counterweights on the housing and motor to ensure even weight distribution to maintain the balance of the test structure module.

4. The high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system according to claim 1, characterized in that: Both ends of the motor housing are coaxially mounted in the housing via flanges.

5. The high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system according to claim 1, characterized in that: The water tank is provided with a water inlet, a water outlet and a propeller shaft mounting hole. The water inlet and the water outlet are both equipped with valves for controlling on and off and adjusting the flow. The propeller shaft mounting hole is dynamically sealed to the propeller shaft, which can ensure sealing while selecting rotation.

6. The high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system according to claim 1, characterized in that: The quick-disassembly tooling module includes an electric cylinder, a flexible rope, a hook and a gantry bracket. The gantry bracket is installed on the basic platform as a suspension support. Two electric cylinders are symmetrically installed on the top crossbeam of the gantry bracket, and their output ends are fixedly connected to the roots of the flexible ropes respectively; the free end of the head of the flexible rope passes through the guide hole on the gantry bracket and is connected to the hook; the hook is installed in cooperation with the lifting ring on the test structure module shell, and the vertical height position of the test structure module can be adjusted by driving the electric cylinder.

7. The high-precision vibration simulation experimental device for a propeller-shaft-shell coupling system according to claim 1, characterized in that: The method for controlling the external excitation received by the propeller is to adjust the water level in the water tank by adjusting the water inlet and outlet valves of the water tank. The higher the water level, the more propeller blades are immersed in the water, and the greater the external excitation received during the rotation process; the lower the water level, the fewer propeller blades are immersed in the water, and the smaller the external excitation received during the rotation process.

8. A method for testing the high-precision vibration simulation experimental device of the propeller-shaft-shell coupling system according to any one of claims 1 to 7, characterized in that The specific steps are as follows: Step 1: Layout of the experimental device structure; Based on the actual vibration test requirements, build a high-precision vibration simulation test system for the propeller-shaft-shell coupling system; Step 2: Parameter design and preparation; determine the number of counterweights required based on the model of the underwater vehicle being simulated; determine the overlap angle of the eccentric blocks based on the eccentricity of the motors of different models; and determine the water volume in the water tank based on the external excitations applied to the propeller at different speeds. Step 3: Quickly disassemble the tooling; using the quick disassembly tooling module, install the corresponding counterweights on the motor and the inside of the housing, install the flange to connect the propulsion shaft system and the housing, connect the housings, and adjust the height of the test structure module; Step 4: Verify the feasibility of the coupling system and test method. Based on the test results, compare the test target values ​​and evaluate the performance and reliability of the propeller-shaft-shell coupling system in this vibration test system and method.

9. The testing method according to claim 8, characterized in that: The method for selecting the overlap angle of the eccentric block is to construct a dynamic model of the actual underwater vehicle physical model, obtain the predicted value of the shell vibration acceleration through simulation; then measure the actual value of the shell vibration acceleration through experiment; compare the predicted value of the shell vibration acceleration with the experimental value, and when the two basically coincide, determine that the corresponding eccentric angle is a certain deflection angle; the eccentric block is a cylindrical structure with a cross-section that is approximately semicircular.

10. The testing method according to claim 9, characterized in that: The dynamic model method for constructing the actual underwater vehicle physical model is: The physical model of the underwater vehicle is simplified to a propeller-shaft-shell double-beam model, where the shell is a hollow beam and the propulsion shaft is a solid beam. The finite element method is used to derive the dynamic differential equation as follows: (1) in, They represent the total mass matrix, stiffness matrix, damping matrix, and gyroscope matrix of the double-beam system respectively. represents the system displacement at time t; is the angular velocity of the propulsion shaft system; is the gravity acting on the system; The Hertzian contact force between the propulsion shaft and the housing bearing, i.e., the nonlinear restoring force, is expressed as (2) in, represents the Hertzian contact stiffness coefficient; , is the Heaviside function of the bearing, is the radial clearance of the bearing, Indicates the displacement of the center of the bearing inner ring in the radial horizontal and vertical directions. It represents the Hertzian contact force applied in the horizontal radial direction at the center of the inner ring of the bearing. It represents the Hertzian contact force applied in the vertical direction to the center of the inner ring of the bearing; Indicates the total number of bearing balls, j Indicates the bearing ball serial number; For the j Angular position of each ball; is the rotational eccentric force, expressed as (3) in, 、 are applied in the radial horizontal and radial vertical directions of the propulsion shaft system respectively; The eccentric mass and eccentricity of the propeller-shaft-shell double beam model are based on the actual model of the underwater vehicle rotating body mass. Deviation from assembly Equivalent replacement; The system dynamic response is calculated according to formula (1), and the coincidence angle of the eccentric block is found by comparing it with the experimentally measured response signal.

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