Icebreaking ship overtaking coupling hydrodynamic test measurement method

Abstract

The present application relates to a kind of ice area ship overtaking coupling hydrodynamic test measurement methods, comprising S1, ship model processing and ice area channel simulation;S2, the route of ship model one is set and fitting out navigation route;S3, the route of ship model two is set;S4, the lateral distance calculation of ship model one and ship model two;S5, through control system control ship model two steering until interval reaches target value, ship model overtaking motion simulation is completed, simultaneously through three-component force measuring sensor, coupling hydrodynamic in whole ship overtaking control simulation process is measured in real time.The present application is simulated when coupling hydrodynamic model test is carried out in towing tank, and ship model one is realized by trailer linear navigation at constant speed, and lateral interval control algorithm, model propulsion system, model rudder device, rudder actuator, model controller realizes the real-time overtaking control of ship model two, so as to realize the simulation of ship overtaking condition simulation ship model test, and simulate the relationship between the distance of two ship models and coupling hydrodynamic.

Description

Technical Field

[0001] This invention relates to the field of ship hydrodynamics technology, and in particular to a method for measuring the coupled hydrodynamic test of a ship overtaking in ice-covered areas. Background Technology

[0002] When navigating in ice-covered areas, the narrowness of the channel and the high resistance of ice reduce maneuverability. Due to the variable course and factors such as drifting ice, ship speed, maneuverability, and destination, overtaking maneuvers are inevitable. Existing data shows that collisions caused by overtaking are frequent.

[0003] The main reason is that in narrower channels, when ships are overtaking each other, the relative speed is low and the duration is long, which makes it easy for them to interact. As a result, both ships are affected by unbalanced forces or turning moments, causing them to deviate from their respective routes or turn, thus leading to a collision between the two ships.

[0004] However, so far, there is no detailed data on the relationship between force and distance, which urgently needs to be measured. Therefore, we propose a measurement method for coupled hydrodynamic test of ship overtaking in ice-covered areas. Summary of the Invention

[0005] To address the shortcomings of existing production technologies, the applicant provides a method for measuring the coupling hydrodynamics of ships overtaking in ice-covered areas. This method enables simulation tests of ship overtaking conditions using model ships, and simulates the relationship between the distance between two model ships and the coupling hydrodynamics.

[0006] The technical solution adopted in this invention is as follows:

[0007] 1. A method for measuring the coupled hydrodynamics of a ship overtaking in ice-covered areas, characterized in that it includes:

[0008] S1. Ship model fabrication and simulation of ice-covered waterways: Two ship models and a simulated ice-covered waterway are fabricated according to the scale of the real ship and the actual ice-covered waterway. The two ship models are Ship Model 1 and Ship Model 2.

[0009] S2. Set the route of model ship one; model ship one is suspended on the simulated ice zone waterway and connected to the trailer through the connecting device. The trailer moves along the track distributed along the simulated ice zone waterway. The connecting device is also equipped with a three-part force measurement sensor. At the same time, as the trailer moves, the navigation trajectory curve of model ship one is fitted.

[0010] Ax + By + C = 0 (1)

[0011] In the formula, coefficients A, B, and C are the coefficients of the linear trajectory equation generated by the motion of the ship model;

[0012] S3. Set the route of model ship 2; model ship 2 is located to the side and rear of the path of model ship 1. Model ship 2 is equipped with a model propulsion device, actively navigates in the simulated ice zone channel, and overtakes model ship 1.

[0013] S4. Calculation of the lateral distance between model ship 1 and model ship 2: Substitute the parameters in formula (1) at the fitting point and the measured coordinates (x1, y1) of the center of gravity of model ship 2 into formula (2) to obtain the lateral distance value.

[0014]

[0015] In the formula, (x1, y1) are the coordinates of the ship model's center of gravity in a fixed coordinate system;

[0016] S5. The control system controls the steering of the ship model until the distance reaches the target value, thus completing the simulation of the ship model chasing and overtaking motion. At the same time, the coupling hydrodynamics of the entire ship chasing and overtaking maneuver simulation process are measured in real time through the three-part force measurement sensor.

[0017] Optionally, the draft deviation between the first and second ship models is within 20%.

[0018] Optionally, the simulated ice zone channel is set in a straight line and the water temperature is kept at 0 degrees Celsius, with a small amount of ice slag inside.

[0019] Optionally, the trailer moves along the track under the power provided by the motor. The connecting device includes a base, which is fixedly connected to the three-part force measuring sensor and then connected and fixed to the cornering mechanism on the trailer through the boat model connecting support rod to achieve a rigid connection.

[0020] Optionally, the second model ship is equipped with a model propulsion device, a model servo device, a servo actuator, and a model controller. The second model ship achieves free forward navigation through its own model propulsion device, and achieves steering and course change through the model servo device and servo actuator. The second model ship is also connected to an optical receiver for detecting position, and the second model ship is also equipped with sensors for measuring parameters such as heading angle, heading angular velocity, pitch angle, rudder angle, and propeller speed.

[0021] Optionally, it also includes an optical measuring device, which is arranged at the upper end of the simulated ice channel, establishes a coordinate system based on the simulated ice channel, tracks the position change of the optical receiver in real time, and thus obtains the track coordinate value of the second ship model in real time.

[0022] Optionally, in S5, the control system uses a two-parameter control algorithm to send execution signals to the model controller of the second ship model in real time. The model controller sends execution rudder angle signals to the rudder actuator in real time to perform rudder angle change manipulation, thereby realizing steering control simulation.

[0023] Optionally, the two-parameter control algorithm is shown in the following equation:

[0024]

[0025] θ is the rudder angle of model ship two, and α is the heading angle of model ship two. β is the angular velocity of the second ship model; β is the lateral distance between the first and second ship models. Let k1, k2, k3, and k4 be the differential values ​​of the lateral spacing between model ship 1 and model ship 2, and k1, k2, k3, and k4 be the coefficients of the spacing control algorithm.

[0026] The beneficial effects of this invention are as follows:

[0027] This invention achieves a simulated overtaking maneuver of a ship model during a coupled hydrodynamic model test in a towed pool. The first ship model is towed to achieve constant-speed straight-line navigation, while the second ship model is controlled in real-time via a spacing control algorithm, a propulsion system, a rudder mechanism, a rudder actuator, and a controller. This simulates the relationship between the distance between the two ship models and the coupled hydrodynamic forces. During the simulated overtaking maneuver, the following parameters can be measured: the heading angle, angular velocity, rudder angle, and propeller speed of the second ship model; the trajectory and towing speed of the first ship model; and the relationship between the change in distance between the two ship models and the corresponding coupled unsteady hydrodynamic forces. This experimental measurement system is simple to operate and solves the problems of simulating unsteady processes and measuring the coupled hydrodynamic forces between ship models during overtaking maneuvers on the water surface.

[0028] Meanwhile, in this embodiment, the ship model's lateral spacing dual-parameter control method and overtaking maneuvering model test process can be used to simulate the ship-to-ship overtaking maneuvering process through ship model tests in a water tank laboratory. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the present invention.

[0030] in:

[0031] 1. Track; 2. Trailer; 3. Turning mechanism; 4. Ship model connecting support rod; 5. Three-part force measurement sensor; 6. Ship model one; 7. Base; 8. Ship model two; 9. Optical receiver bracket; 10. Optical receiver; 11. Model propulsion device; 12. Model servo device; 13. Servo actuator; 14. Model control. Detailed Implementation

[0032] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0033] like Figure 1As shown, this embodiment discloses a test method for simulating ship overtaking maneuvers and measuring hydrodynamics using a ship model. This invention is a ship model test system for simulating ship overtaking maneuvers and measuring coupled hydrodynamics. It mainly consists of two ship models, a trailer 2, a connecting device, a three-force measurement sensor 5, an optical measurement device, and a control system. One ship model is fixed together via the three-force measurement sensor 5 and the connecting device, which is then installed below the trailer 2 to achieve movement along a specific path. The overtaking ship model achieves free self-propulsion control through a model propulsion device 11 and a model steering device. This allows for the simulation of ship overtaking maneuvers and the determination of the relationship between the distance and coupled hydrodynamics between the two ship models. This test and measurement system is simple to operate and solves the problems of simulating unsteady processes and measuring coupled hydrodynamics between ship models during ship overtaking maneuvers.

[0034] The specific measurement method includes the following steps:

[0035] S1. Ship model fabrication and simulation of ice-covered waterways: Two ship models and a simulated ice-covered waterway are fabricated according to the scale of the real ship and the actual ice-covered waterway. The two ship models are Ship Model 1 6 and Ship Model 2 8.

[0036] The draft deviation between model 6 and model 8 is within 20%. In this embodiment, model 6 and model 8 use the same draft to reduce the error caused by the different drafts. The simulated ice channel is set in a straight line and the water temperature is kept at 0 degrees Celsius. A small amount of ice debris is set in it to increase the navigation resistance, thereby simulating the ice channel dug out under actual conditions.

[0037] S2. Set the route of model ship 6; arrange track 1 along the simulated ice zone waterway, and set a trailer 2 that moves along the track direction on track 1. Model ship 6 is connected to trailer 2 through model ship connecting support rod 4 and moves along track 1. The connection part is also equipped with a three-part force measuring sensor 5 to measure the interaction force. At the same time, model ship 6 is suspended in the simulated ice zone waterway and the navigation trajectory curve is fitted.

[0038] Ax + By + C = 0 (1)

[0039] In the formula, coefficients A, B, and C are the coefficients of the linear trajectory equation generated by the motion of the ship model-6;

[0040] To improve the connection effect, in this embodiment, the trailer 2 moves along the track 1 under the power provided by the motor. The connection device includes a base 7, which is fixedly connected to the three-part force measuring sensor 5, and then connected and fixed to the cornering mechanism 3 on the trailer 2 through the boat model connecting support rod 4 to achieve a rigid connection. The trailer 2 drives the first boat model 6 to achieve straight-line navigation at a constant test speed V1, realizing stable straight-line navigation simulation in front of the second boat model 8.

[0041] S3. Set the course of model ship 28; model ship 28 is located to the side and rear of the moving path of model ship 16. Model ship 28 is equipped with a model propulsion device 11 and actively navigates in the simulated ice channel through remote control, and overtakes model ship 16 at a speed of V2. Model ship 28 is also equipped with sensors that measure parameters such as heading angle, heading angular velocity, pitch angle, rudder angle, and propeller speed.

[0042] In this embodiment, as Figure 1 As shown, the overtaking ship model 2 8 is equipped with a model propulsion device 11, a model servo device 12, a servo actuator 13, and a model controller 14. The ship model 2 8 achieves free forward navigation through its own model propulsion device 11, and achieves steering and course change navigation through the model servo device 12 and the servo actuator 13.

[0043] The second model ship 8 is also connected to an optical receiver 10 for position detection and positioning. The optical receiver 10 is fixed to the upper end of the second model ship 8 by an optical receiver bracket 9.

[0044] S4, Calculation of the lateral distance between model ship 1 (6) and model ship 2 (8) (i.e.) Figure 1 Distance in the Y-axis direction); Substitute the parameters in formula (1) at the fitting point, and the coordinates (x1, y1) of the center of gravity of ship model 28 measured by S3 into formula (2) to obtain the lateral spacing value;

[0045]

[0046] In the formula (x1, y 1) The coordinates are the coordinate values ​​of the center of gravity of the ship model II in a fixed coordinate system;

[0047] During the model test, the trajectory coordinates of model ship 28 are transmitted via an optical measuring device positioned at the upper end of the simulated ice-covered waterway. A coordinate system is established using the simulated ice-covered waterway as a reference, and the device tracks the position changes of the optical receiver 10 in real time, thereby obtaining the trajectory coordinates of model ship 28. The trajectory coordinates are then transmitted to the subsequent control system to control model ship 28.

[0048] S5. The control system controls the steering of the second ship model until the distance reaches the target value, thus completing the simulation of the ship model chasing and overtaking motion. At the same time, the coupling hydrodynamics of the entire ship chasing and overtaking maneuver simulation process is measured in real time through the three-part force measurement sensor 5 between the first ship model 6 and the trailer 2.

[0049] In this embodiment, the control system includes a model servo device 12 and a servo actuator 13 to realize the change of rudder angle, which can control the relative distance between the two ship models and realize driving at different distances, especially driving in parallel, while measuring the corresponding coupled hydrodynamics.

[0050] In this embodiment, the control system uses a dual-parameter control algorithm to send execution signals to the model controller 14 of the ship model 2 8 in real time. The model controller 14 sends execution rudder angle signals to the rudder actuator 13 in real time to perform rudder angle change manipulation, thereby realizing steering control simulation.

[0051] The two-parameter control algorithm is shown in equation (3).

[0052]

[0053] θ is the rudder angle of model ship 2(8), and α is the heading angle of model ship 2(8). β is the angular velocity of the heading of model 2 (8); β is the lateral distance between model 1 (6) and model 2 (8). K is the differential value of the lateral spacing between model 1 (6) and model 2 (8), and k1, k2, k3, and k4 are the coefficients of the spacing control two-parameter algorithm.

[0054] This design facilitates both control of the ship models and measurement of the coupled hydrodynamic forces between them. Ship model 1 (6) is towed forward by trailer 2, while ship model 2 (8) accelerates from a distance behind using model propulsion device 11 to catch up with ship model 1 (6). Simultaneously, the distance between the two ship models is controlled through spacing calculation and a dual-parameter lateral spacing control algorithm. Ultimately, the two ship models maintain a certain lateral spacing and move forward in parallel at the same speed, while the coupled hydrodynamic forces are measured.

[0055] During the coupled hydrodynamic model test in the towed pool, model 16 achieves constant-speed straight-line navigation via trailer 2. A dual-parameter control algorithm, model propulsion device 11, model rudder device 12, rudder actuator 13, and model controller 14 enable real-time overtaking maneuvering control of model 28. This achieves a simulated overtaking maneuver test, simulating the relationship between the distance and coupled hydrodynamics between the two models. Through the simulated overtaking motion test, the following parameters can be measured: the heading angle, heading angular velocity, rudder angle, and propeller speed of model 28; the trajectory and towing speed of model 16; and the relationship between the change in distance between model 16 and model 28 and the corresponding coupled unsteady hydrodynamics. This experimental measurement system is simple to operate and solves the problems of simulating unsteady processes and measuring the coupled hydrodynamics between models during overtaking maneuvering.

[0056] Meanwhile, in this embodiment, the ship model lateral spacing control method and overtaking maneuvering model test process can be used to simulate the ship-to-ship overtaking maneuvering process through ship model tests in a water tank laboratory.

[0057] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the protection scope of the present invention, any modifications may be made.

Claims

1. A method for measuring the coupled hydrodynamics of a ship overtaking in ice-covered areas, characterized in that, include: S1. Ship model processing and simulation of ice-covered waterways: Two ship models and a simulated ice-covered waterway were processed according to the scale of the real ship and the actual ice-covered waterway. The two ship models are ship model one (6) and ship model two (8). S2. Set the route of model ship 1 (6); model ship 1 (6) is suspended on the simulated ice zone waterway and connected to the trailer (2) through the connecting device. The trailer (2) moves along the track (1) distributed along the simulated ice zone waterway. The connecting device is also equipped with a three-part force measurement sensor (5). At the same time, as the trailer (2) moves, the navigation trajectory curve of model ship 1 (6) is fitted. （1） In the formula, coefficients A, B, and C are the coefficients of the trajectory straight line equation generated by the motion of the ship model (6); S3. Set the route of the second model ship (8); the second model ship (8) is located to the side and rear of the movement path of the first model ship (6). The second model ship (8) is equipped with a model propulsion device (11) and actively navigates in the simulated ice channel and overtakes the first model ship (6). S4. Calculation of the lateral distance between model 1 (6) and model 2 (8); Substitute the parameters in formula (1) at the fitting point and the measured coordinates (x1, y1) of the centroid of model 2 (8) into formula (2) to obtain the lateral spacing value. （2） In the formula (x 1， y1) The coordinates are the coordinates of the center of gravity of the ship model 2 (8) in the fixed coordinate system; S5. The control system controls the steering of the ship model until the distance reaches the target value, thus completing the ship model overtaking motion simulation. At the same time, the coupling hydrodynamics of the entire ship overtaking maneuver simulation process is measured in real time through the three-part force measurement sensor (5).

2. The method for measuring coupled hydrodynamics in ice-covered areas by overtaking vessels as described in claim 1, characterized in that: The draft deviation of the first (6) and the second (8) of the ship model is within 20%.

3. The method for measuring coupled hydrodynamics in ice-covered areas by overtaking vessels as described in claim 1, characterized in that: The simulated ice zone waterway is set in a straight line and the water temperature is kept at 0 degrees Celsius, with a small amount of ice slag inside.

4. The method for measuring coupled hydrodynamics of a ship overtaking in ice-covered areas as described in claim 1, characterized in that: The trailer (2) moves along the track (1) under the power provided by the motor. The connecting device includes a base (7), which is fixedly connected to the three-part force measuring sensor (5), and then connected and fixed to the corner mechanism (3) on the trailer (2) through the boat model connecting support rod (4) to achieve a rigid connection.

5. The method for measuring coupled hydrodynamics in ice-covered areas by overtaking vessels as described in claim 1, characterized in that: The second model ship (8) is equipped with a model propulsion device (11), a model servo device (12), a servo actuator (13), and a model controller (14). The second model ship (8) achieves free forward navigation through its own model propulsion device (11), and achieves steering and course change driving through the model servo device (12) and the servo actuator (13). The second model ship (8) is also connected to an optical receiver (10) for detecting position. The second model ship (8) is also equipped with sensors for measuring heading angle, heading angular velocity, pitch angle, rudder angle, and propeller speed parameters.

6. The method for measuring coupled hydrodynamics in ice-covered areas by overtaking vessels as described in claim 5, characterized in that: It also includes an optical measuring device, which is placed at the upper end of the simulated ice channel. A coordinate system is established based on the simulated ice channel to track the position change of the optical receiver (10) in real time, thereby obtaining the track coordinate value of the second ship model (8) in real time.

7. The method for measuring coupled hydrodynamics of a ship overtaking in ice-covered areas as described in claim 6, characterized in that: The control system in S5 uses a dual-parameter control algorithm to send execution signals to the model controller (14) of the ship model 2 (8) in real time. The model controller (14) sends execution rudder angle signals to the rudder actuator (13) in real time to perform rudder angle change manipulation and realize steering control simulation.

8. The method for measuring coupled hydrodynamics in ice-covered areas by overtaking vessels as described in claim 7, characterized in that: The two-parameter control algorithm is shown in equation (3) below: （3） For the rudder angle of model ship two (8), For the heading angle of the second (8) ship model, For model ship two (8), the heading angular velocity; The lateral spacing between ship model one (6) and ship model two (8) is... Let be the differential value of the lateral spacing between ship model one (6) and ship model two (8). , , , These are the coefficients for the spacing control algorithm.

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