A piston-type wave making system and test platform for ice breaking and ice disposal

Abstract

A plunger wave making system and test platform for ice breaking and ice removal relates to the field of ship and ocean engineering, in particular to the field of wave making technology. In order to solve the problem that sea ice continuously collides with the ocean platform, thereby causing fatigue damage to the platform structure, the present application provides the following scheme: a plunger wave making system for ice breaking and ice removal, the system comprises: a hemispherical plunger, a driving device and a control system; the driving device comprises an actuator; the control system sends a pulse signal to the driving device; the driving device controls the movement of the actuator according to the pulse signal; the actuator drives the hemispherical plunger to make linear reciprocating motion; the end of the hemispherical plunger is a hemispherical shell. The present application is suitable for ice breaking and ice removal in the polar region and verifying the effect of ice breaking and ice removal.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding and marine engineering, and more specifically to the field of wave generation technology. Background Technology

[0002] Since the 20th century, various types of offshore platforms have been deployed in polar regions worldwide, providing a guarantee for human survival and development. However, polar offshore platforms face complex environments such as low temperatures and sea ice. Furthermore, accidents can cause not only economic losses but also incalculable damage to the polar environment. Sea ice, driven by wind, waves, and currents, drifts and interacts with the offshore platform, causing compression, bending, fracturing, and accumulation. The resulting load is known as ice load, and its destructive power is far greater than other environmental loads. When the excitation frequency of sea ice collisions approaches the platform's natural frequency, resonance can easily be induced, thus affecting the platform's safe operation.

[0003] Currently, polar offshore platforms primarily enhance their operational safety and stability by installing ice-breaking cones or ramps to resist ice. Large ice floes bend and break upon contact with these structures, reducing the impact on the platform. However, the accumulation of numerous ice fragments near the platform, constantly colliding with it, can eventually lead to structural fatigue failure. Furthermore, large ice floes may exceed the load-bearing capacity of these passive ice-resistant structures. Therefore, it is necessary to design an active ice-resistant structure that employs different strategies to address varying sea ice conditions. One such active ice-resistant structure is the plunger-type wave generator, which generates the desired target waveform by controlling the vertical movement of a plunger. When the sea ice's strain exceeds its ultimate strain under wave action, the ice breaks up and is displaced by the waves, moving away from the platform. Summary of the Invention

[0004] To address the problem of fatigue damage to offshore platforms caused by continuous collisions with sea ice, this invention provides the following solution:

[0005] A plunger-type wave-generating system for ice breaking and ice removal, the system comprising: a hemispherical plunger, a drive device, and a control system;

[0006] The drive device includes an actuator;

[0007] The control system sends pulse signals to the drive device;

[0008] The drive device controls the movement of the actuator according to the pulse signal;

[0009] The actuator drives the hemispherical plunger to perform linear reciprocating motion;

[0010] The end of the hemispherical plunger is a hemispherical outer shell.

[0011] Furthermore, the hemispherical plunger also includes: two support plates and a transmission rod;

[0012] Both support plates are fixed inside the hemispherical shell;

[0013] The two support plates are parallel to each other and coaxial.

[0014] Both support plates are cross-shaped plates;

[0015] Both support plates are welded and fixed to the inner wall of the hemispherical shell;

[0016] The transmission rod is coaxial with the hemispherical shell;

[0017] The transmission rod passes through the two support plates and is fixedly connected to the two support plates;

[0018] The end of the transmission rod is fixedly connected to the inside of the hemispherical shell.

[0019] Furthermore, the hemispherical plunger also includes: 8 reinforcing ribs;

[0020] The eight reinforcing ribs are sequentially welded and fixed at the eight joints between the two support plates and the spherical shell.

[0021] Furthermore, the hemispherical plunger also includes: a connecting flange;

[0022] The connecting flange is used to fix the transmission rod to the support plate.

[0023] Furthermore, the driving device also includes: a servo motor and a driver;

[0024] The moving part of the actuator is a piston rod;

[0025] The piston rod is used to connect the power signal output terminal of the servo motor to the hemispherical plunger, driving the hemispherical plunger to perform linear reciprocating motion;

[0026] The servo motor is equipped with an encoder, which is used to collect the rotation angle and speed information of the servo motor and send the rotation angle and speed information to the driver.

[0027] The driver is used to take the received rotation angle and speed information as feedback parameters of the PID control algorithm, take the pulse signal as input parameters of the PID control algorithm, obtain a drive signal, and send the drive signal to the servo motor.

[0028] Furthermore, the control system includes: a limit magnetic sensor, an origin magnetic sensor, a programmable logic controller, and a host computer;

[0029] The limit magnetic sensor is used to detect whether the piston rod has reached the limit position and send the detection result to the programmable logic controller.

[0030] The origin magnetic sensor is used to detect whether the piston rod has reached the origin position and sends the detection result to the programmable logic controller.

[0031] The host computer is used to send the duty cycle and frequency information of the given pulse signal to the programmable logic controller.

[0032] The programmable logic controller is used to generate a pulse signal and send it to the driver based on the duty cycle and frequency information of the received pulse signal.

[0033] An experimental platform for ice breaking and ice removal, the platform comprising: a wave generation system and a data acquisition system;

[0034] The acquisition system includes: a wave information acquisition device, a strain information acquisition device, a motion trajectory measurement device, and a computer;

[0035] The wave information acquisition device is used to acquire wave height information in real time and send the wave height information to a computer;

[0036] The motion trajectory measuring device is used to collect the displacement information of the floating ice in real time and send the displacement information to the computer;

[0037] The strain information acquisition device includes a model ice, which is used to acquire the strain information of the model ice in real time and send the strain information to a computer.

[0038] The computer is used to perform a fast Fourier transform on all received information, converting the time-domain signal into a frequency-domain signal, and analyzing the amplitude and period of the frequency-domain signal; when the amplitude is less than expected, it generates a wave-generating adjustment signal to the control system in the wave-generating system.

[0039] The control system is used to adjust the pulse signal according to the wave generation adjustment signal.

[0040] Furthermore, the strain information acquisition device also includes: strain gauges and strain measuring instruments;

[0041] The strain gauges are tightly fitted and fixed to the surface of the model ice;

[0042] The strain gauge is used to collect the deformation of the strain gauge and convert the collected results into strain information of the model ice, which is then sent to the computer.

[0043] Furthermore, the wave information acquisition device includes a wave height meter and a digital signal acquisition instrument;

[0044] The wave height meter is used to collect wave height information and send the wave height information to the digital signal acquisition instrument;

[0045] The digital signal acquisition instrument is used to convert the wave height information and then send it to the computer.

[0046] Furthermore, the motion trajectory measurement device is implemented using a camera;

[0047] The camera is used to collect image information of the experimental area in real time and send the image information to the computer;

[0048] The computer is used to analyze the acquired real-time image information to obtain the displacement information of the floating ice. The beneficial effects of this invention are:

[0049] 1. A plunger-type wave generation method was adopted to achieve omnidirectional annular wave generation. Compared with other wave generation methods, it can not only effectively break ice, but also keep the broken floating ice fragments away from the offshore platform, avoiding secondary collisions and reducing the damage caused by ice-induced vibrations.

[0050] 2. By placing the wave generation system and the information acquisition system under the same framework, the experimental equipment and measuring instruments are combined, which effectively simplifies the operation steps and reduces the difficulty of debugging in the experiment.

[0051] 3. By using feedback of wave information, precise control of wave generation can be achieved, enabling closed-loop control.

[0052] 4. By combining wave height meters, video acquisition systems, and analysis software, the interaction between ice waves can be studied. The results of the analysis software can be verified by the wave height meters, while the results of the visual analysis software can fill in the gaps in the wave height meters' data, effectively expanding the scope of the study. Attached Figure Description

[0053] Figure 1 This is an overall effect diagram of the plunger wave generation system in this invention;

[0054] Figure 2 This is an overall rendering of the hemispherical plunger of the present invention;

[0055] Figure 3 This is an overall rendering of the piston plate, servo motor, and connecting plate of the present invention.

[0056] Figure 4 This is an overall rendering of the connecting plate and fixing plate of the present invention;

[0057] Figure 5This is a partial enlarged view of the plunger wave generation system in this invention;

[0058] Figure 6 This is an overall rendering of the invention;

[0059] Figure 7 This is an overall effect diagram of the strain information acquisition device of the data acquisition system in this invention;

[0060] Figure 8 This is an overall effect diagram of the wave height information acquisition device of the data acquisition system in this invention;

[0061] Figure 9 This is an overall effect diagram of the motion trajectory measurement device of the data acquisition system in this invention;

[0062] In the diagram: 1. Hemispherical shell, 2. Support plate, 3. Reinforcing rib, 4. Connecting flange, 5. Transmission rod, 6. Piston rod, 7. Servo motor, 8. Connecting plate, 9. Fixing plate, 10. Limit magnetic sensor, 11. Origin magnetic sensor, 12. Driver, 13. Programmable logic controller, 14. Host computer, 15. Model ice, 16. Strain gauge, 17. Strain measuring instrument, 18. Computer, 19. Wave height meter, 20. Digital signal acquisition instrument, 21. Camera. Detailed Implementation

[0063] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0064] Implementation Method 1: Combining Figure 1 This embodiment describes a plunger-type wave-generating system for ice breaking and ice removal, the system comprising: a hemispherical plunger, a drive device, and a control system;

[0065] The drive device includes an actuator;

[0066] The control system sends pulse signals to the drive device;

[0067] The drive device controls the movement of the actuator according to the pulse signal;

[0068] The actuator drives the hemispherical plunger to perform linear reciprocating motion;

[0069] The end of the hemispherical plunger is a hemispherical outer shell 1.

[0070] Implementation Method Two: Combining Figure 2 This embodiment further defines the plunger-type wave-generating system for ice breaking and ice removal described in Embodiment 1. In this embodiment, the hemispherical plunger also includes two support plates 2 and a transmission rod 5.

[0071] Both support plates 2 are fixed inside the hemispherical shell 1;

[0072] The two support plates 2 are parallel to each other and coaxial;

[0073] Both support plates 2 are cross-shaped plates;

[0074] Both support plates 2 are welded and fixed to the inner wall of the hemispherical shell 1;

[0075] The transmission rod 5 is coaxial with the hemispherical outer shell 1;

[0076] The transmission rod 5 passes through the two support plates 2 and is fixedly connected to the two support plates 2;

[0077] The end of the transmission rod 5 is fixedly connected to the inside of the hemispherical shell 1.

[0078] The hemispherical plunger, as the main moving component, has a stainless steel outer shell to effectively reduce corrosion. Simultaneously, the hemispherical plunger is constantly impacted by water, placing a significant stress on the shell; therefore, the use of steel ensures overall strength requirements, minimizes deformation, and guarantees wave generation accuracy. Inside the hemispherical plunger, there are two support plates, each composed of two perpendicular support plates, further ensuring that the outer shell does not undergo significant deformation. The drive rod has internal threads at its top, allowing it to connect to the connector at the top of the piston rod, thereby driving the entire hemispherical plunger in a vertical reciprocating motion, ultimately achieving omnidirectional annular wave generation.

[0079] Implementation Method 3: This implementation method is a further definition of the plunger-type wave-generating system for ice breaking and ice removal described in Implementation Method 1. In this implementation method, the hemispherical plunger further includes: 8 reinforcing ribs 3;

[0080] The eight reinforcing ribs 3 are sequentially welded and fixed at the eight joints between the two support plates 2 and the spherical shell 1.

[0081] Additional reinforcing ribs are present at the welded joint between the support plate and the outer shell, thereby improving the reliability of the connection between the support plate and the outer shell.

[0082] Implementation Method 4: This implementation method is a further definition of the plunger-type wave-generating system for ice breaking and ice removal described in Implementation Method 1. In this implementation method, the hemispherical plunger further includes: a connecting flange 4.

[0083] The connecting flange 4 is used to fix the transmission rod 5 to the support plate 2.

[0084] A circular hole is left in the middle of the support plate for the transmission rod to pass through. The transmission rod is connected to each support plate through a connecting flange and tightened with non-standard nuts and bolts to improve overall stability and reduce vibration.

[0085] Implementation Method 5: Combining Figure 3 This embodiment further defines the plunger wave-generating system for ice breaking and ice removal described in Embodiment 1. In this embodiment, the driving device further includes a servo motor 7 and a driver 12.

[0086] The moving part of the actuator is the piston rod 6;

[0087] The piston rod 6 is used to connect the power signal output end of the servo motor 7 to the hemispherical plunger, driving the hemispherical plunger to perform linear reciprocating motion;

[0088] The servo motor 7 is equipped with an encoder, which is used to collect the rotation angle and speed information of the servo motor 7 and send the rotation angle and speed information to the driver 12;

[0089] The driver 12 is used to take the received rotation angle and speed information as feedback parameters of the PID control algorithm, take the pulse signal as input parameters of the PID control algorithm, obtain a drive signal, and send the drive signal to the servo motor 7.

[0090] The servo motor enables the piston rod to reciprocate vertically, offering high control precision and good stability at low speeds. An internal encoder within the servo motor provides high-precision position control. The encoder feeds back information such as the motor's rotation angle and speed, transmitting this data to the servo driver to ensure motion accuracy and stability. The servo motor driver receives signals from the encoder and adjusts the output voltage and current using a PID control algorithm to control the motor's movement. Additionally, the driver receives pulse signals from the controller, converting them into motor motion commands to ultimately drive the servo motor. In summary, this drive system provides feedback and adjustments, effectively ensuring stable and precise motion. During installation, the piston rod is secured to the servo motor with threads. Bolts are then passed through pre-drilled holes in the servo motor and connecting plate, and nuts are tightened to connect and secure the servo motor and connecting plate. The connecting plate is then fixed to the mounting plate, and the mounting plate is finally secured to the tank trailer using bolts and nuts. The connection plate and mounting plate are then... Figure 4 As shown.

[0091] Implementation Method Six: Combination Figure 5This embodiment further defines the plunger-type wave-generating system for ice breaking and ice removal described in Embodiment 5. In this embodiment, the control system includes: a limit magnetic sensor 10, a origin magnetic sensor 11, a programmable logic controller 13, and a host computer 14.

[0092] The limit magnetic sensor 10 is used to detect whether the piston rod 6 has reached the limit position and send the detection result to the programmable logic controller 13;

[0093] The origin magnetic sensor 11 is used to detect whether the piston rod 6 has reached the origin position and send the detection result to the programmable logic controller 13.

[0094] The host computer 14 is used to send the duty cycle and frequency information of the given pulse signal to the programmable logic controller 13;

[0095] The programmable logic controller 13 is used to generate a pulse signal and send it to the driver 12 based on the duty cycle and frequency information of the received pulse signal.

[0096] The motion cycle and distance of the hemispherical plunger are set in the computer, and the corresponding real-time motion speed is calculated by the program and transmitted to the PLC. The PLC then adjusts the pulse frequency and duty cycle using pulse width modulation (PWM) technology to regulate the servo motor speed. Compared with microcontrollers, PLCs offer greater flexibility, reliability, expandability, and security, and programming and debugging are also simpler and faster. Magnetic sensors are installed on the servo motor; when the magnet on the piston rod passes by, it sends a signal to the PLC. The positions of the two magnetic sensors serve as the program's limit and origin, respectively. This prevents the piston rod from exceeding its maximum stroke, and the origin serves as the reference point for positioning control. Before the servo motor begins operation, it needs to return to the origin position. Therefore, by changing the origin position, the initial immersion volume of the hemispherical plunger in water can be controlled, thereby changing the wave height. In summary, this control system automatically achieves effective pulse output and precisely controls the speed and direction of the servo motor by providing motion parameters. When the parameters of the generated waves change, only modifications need to be made in the computer.

[0097] Implementation Method Seven: Combining Figure 6 This embodiment describes a platform comprising a wave-generating system and a data acquisition system; the wave-generating system is a plunger-type wave-generating system for ice breaking and ice removal as described in Embodiment 1.

[0098] The acquisition system includes: a wave information acquisition device, a strain information acquisition device, a motion trajectory measurement device, and a computer 18;

[0099] The wave information acquisition device is used to acquire wave height information in real time and send the wave height information to computer 18;

[0100] The motion trajectory measuring device is used to collect the displacement information of the floating ice in real time and send the displacement information to the computer 18;

[0101] The strain information acquisition device includes a model ice 15. The strain information acquisition device is used to acquire the strain information of the model ice 15 in real time and send the strain information to a computer 18.

[0102] The computer 18 is used to perform a fast Fourier transform on all received information, converting the time-domain signal into a frequency-domain signal, and analyzing the amplitude and period of the frequency-domain signal; when the amplitude is less than expected, it generates a wave-generating adjustment signal to the control system in the wave-generating system.

[0103] The control system is used to adjust the pulse signal according to the wave generation adjustment signal.

[0104] The data acquisition system includes wave information acquisition, strain information acquisition, and motion trajectory measurement. By analyzing the wave information, feedback is provided to the wave generation control system. Based on this feedback, relevant parameters can be corrected, effectively improving the accuracy of wave generation. Strain information acquisition and motion trajectory measurement can record and analyze the maximum strain of flat ice and the overall displacement of floating ice fragments, respectively, to verify the feasibility and practical effectiveness of wave-based ice breaking and removal.

[0105] Implementation Method 8: Combining Figure 7 This embodiment further defines the test platform for ice breaking and ice removal described in Embodiment 7. In this embodiment, the strain information acquisition device further includes: strain gauge 16 and strain measuring instrument 17.

[0106] The strain gauge 16 is tightly fitted and fixed to the surface of the model ice 15;

[0107] The strain gauge 17 is used to collect the deformation of the strain gauge 16 and convert the collection results into strain information of the model ice 15 and send it to the computer 18.

[0108] Strain information is acquired using strain gauges and a matching strain measuring instrument. When a strain gauge undergoes mechanical deformation, its resistance changes accordingly, allowing strain information to be collected using the strain measuring instrument. Fixing the strain gauges to the model ice with glue offers advantages such as high sensitivity, wide applicability, ease of installation, and low cost. It also helps analyze the strain of the model ice at different times and locations, and determine potential fracture sites.

[0109] Implementation Method Nine: Combining Figure 8This embodiment further defines the experimental platform for ice breaking and ice removal described in Embodiment Seven. In this embodiment, the wave information acquisition device includes a wave height meter 19 and a digital signal acquisition device 20.

[0110] The wave height meter 19 is used to collect wave height information and send the wave height information to the digital signal acquisition instrument 20;

[0111] The digital signal acquisition device 20 is used to convert the wave height information into a value and then send it to the computer 18.

[0112] The digital wave height meter and its accompanying digital signal acquisition unit are responsible for collecting wave information, obtaining wave height information at every moment, and performing Fast Fourier Transform (FFT) on it to analyze the wave frequency, period, and wave height information. This method offers advantages such as ease of operation, fast analysis speed, and high measurement accuracy. The obtained information is then fed back to the wave generation system to achieve closed-loop control and effectively improve wave generation accuracy. In addition, two wave height meters are arranged in the wave propagation direction. Comparative analysis of the data allows for the study of wave transmission and reflection, expanding the scope of research on ice-wave interaction.

[0113] Implementation Method 10: Combining Figure 9 This embodiment further defines the experimental platform for ice breaking and ice removal described in Embodiment Seven. In this embodiment, the motion trajectory measuring device is implemented using a camera 21.

[0114] The camera 21 is used to collect image information of the experimental area in real time and send the image information to the computer 18;

[0115] The computer 18 is used to analyze the obtained real-time image information to obtain floating ice displacement information.

[0116] For the movement of broken ice fragments, video information is collected using a camera mounted above the model ice. Combined with motion analysis software, the trajectory of the fragments on the water surface is obtained, aiding in the analysis of velocity and acceleration information at different locations. Simultaneously, during experiments, the measurement system can acquire wave periods and wave heights using corresponding software, thus enabling auxiliary analysis even in locations without wave height meters, and studying the interaction between ice and waves.

Claims

1. A test platform for ice breaking and ice removal, characterized in that, The platform includes: a wave generation system and a data acquisition system; The wave-generating system is a plunger-type wave-generating system used for ice breaking and ice removal, specifically: Hemispherical plunger, drive mechanism, and control system; The drive device includes an actuator; The control system sends pulse signals to the drive device; The drive device controls the movement of the actuator according to the pulse signal; The actuator drives the hemispherical plunger to perform linear reciprocating motion; The end of the hemispherical plunger is a hemispherical shell (1). The hemispherical plunger also includes: two support plates (2) and a transmission rod (5); Both support plates (2) are fixed inside the hemispherical shell (1); The two support plates (2) are parallel to each other and coaxial; Both support plates (2) are cross-shaped plates; Both support plates (2) are welded and fixed to the inner wall of the hemispherical shell (1); The transmission rod (5) is coaxial with the hemispherical shell (1); The transmission rod (5) passes through the two support plates (2) and is fixedly connected to the two support plates (2); The end of the transmission rod (5) is fixedly connected to the inside of the hemispherical shell (1); The acquisition system includes: a wave information acquisition device, a strain information acquisition device, a motion trajectory measurement device, and a computer (18). The wave information acquisition device is used to acquire wave height information in real time and send the wave height information to a computer (18). The motion trajectory measuring device is used to collect displacement information of floating ice in real time and send the displacement information to a computer (18). The strain information acquisition device includes a model ice (15), which is used to acquire the strain information of the model ice (15) in real time and send the strain information to a computer (18). The computer (18) is used to perform a fast Fourier transform on all received information, convert the time-domain signal into a frequency-domain signal, and analyze the amplitude and period of the frequency-domain signal; when the amplitude is less than expected, it generates a wave-generating adjustment signal to the control system in the wave-generating system. The control system is used to adjust the pulse signal according to the wave generation adjustment signal.

2. The experimental platform for ice breaking and ice removal according to claim 1, characterized in that, The hemispherical plunger also includes: 8 reinforcing ribs (3); The eight reinforcing ribs (3) are sequentially welded and fixed at the eight joints between the two support plates (2) and the hemispherical shell (1).

3. The experimental platform for ice breaking and ice removal according to claim 2, characterized in that, The hemispherical plunger also includes: a connecting flange (4); The connecting flange (4) is used to fix the transmission rod (5) to the support plate (2).

4. The experimental platform for ice breaking and ice removal according to claim 3, characterized in that, The drive device also includes: a servo motor (7) and a driver (12). The moving part of the actuator is the piston rod (6). The piston rod (6) is used to connect the power signal output end of the servo motor (7) to the hemispherical plunger, driving the hemispherical plunger to perform linear reciprocating motion; The servo motor (7) is equipped with an encoder, which is used to collect the rotation angle and speed information of the servo motor (7) and send the rotation angle and speed information to the driver (12). The driver (12) is used to take the received rotation angle and speed information as feedback parameters of the PID control algorithm, take the pulse signal as input parameters of the PID control algorithm, obtain the drive signal, and send the drive signal to the servo motor (7).

5. The experimental platform for ice breaking and ice removal according to claim 4, characterized in that, The control system includes: a limit magnetic sensor (10), an origin magnetic sensor (11), a programmable logic controller (13), and a host computer (14). The limit magnetic sensor (10) is used to detect whether the piston rod (6) has reached the limit position and send the detection result to the programmable logic controller (13). Origin magnetic sensor (11) is used to detect whether the piston rod (6) has reached the origin position and send the detection result to programmable logic controller (13). The host computer (14) is used to send the duty cycle and frequency information of the given pulse signal to the programmable logic controller (13). The programmable logic controller (13) is used to generate a pulse signal and send it to the driver (12) based on the duty cycle and frequency information of the received pulse signal.

6. The experimental platform for ice breaking and ice removal according to claim 5, characterized in that, The strain information acquisition device also includes: strain gauge (16) and strain measuring instrument (17). The strain gauge (16) is tightly attached to and fixed to the surface of the model ice (15); The strain gauge (17) is used to collect the deformation of the strain gauge (16) and convert the collection results into strain information of the model ice (15) and send it to the computer (18).

7. The experimental platform for ice breaking and ice removal according to claim 6, characterized in that, The wave information acquisition device includes a wave height meter (19) and a digital signal acquisition device (20). The wave height meter (19) is used to collect wave height information and send the wave height information to the digital signal acquisition instrument (20). The digital signal acquisition device (20) is used to convert the wave height information into a signal and then send it to the computer (18).

8. The experimental platform for ice breaking and ice removal according to claim 7, characterized in that, The motion trajectory measurement device is implemented using a camera (21); The camera (21) is used to collect image information of the experimental area in real time and send the image information to the computer (18). The computer (18) is used to analyze the obtained real-time image information to obtain floating ice displacement information.

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