Method for obtaining counterweight in rotation test of large sailboat on land

Abstract

The present invention discloses a method for obtaining a counterweight for a rotation test in a land-based test of a large sail, and belongs to the field of marine engineering technology. The present invention first determines the composition of the system in the rotation test, and then, in order to verify the rotation system capability of the sail, the maximum torsional load of the sail in actual ship operation is simulated on land, while considering the loading condition of the tooling, to form a counterweight calculation method for the rotation test, thereby ensuring the smooth implementation of the rotation test. The present invention completes the simulated load of the rotation test in the form of a force couple, and completes the functional test requirements; the present invention designs a counterweight tooling through a combination of a fixed pulley and a movable pulley, which can reduce the size of the counterweight and facilitate the test; the present invention takes into account the mechanical properties of the test tooling itself, and can quickly complete the counterweight acquisition of the rotation test.

Description

Technical Field

[0001] The present invention relates to the field of marine engineering technology, and more particularly to a land-based test of a large sail. Background Art

[0002] With the promulgation and implementation of new low-carbon emission reduction regulations around the world, the global shipping and shipbuilding industries are moving towards greening. Marine sailing devices use wind energy, a clean energy source, as a driving force, setting off a new wave of revolution internationally. DSIC took the lead in conducting the world's first technical research on wing-shaped wind-powered ocean-going cargo ships, breaking through a series of key technologies, including the formulation of rotating test weights in land-based tests.

[0003] Due to the complex marine environment, when using sails, they can complete the function of rotation under wind load to provide maximum thrust for the ship. Summary of the invention

[0004] In order to verify the performance of the rotating motor of the sail in resisting torque, the present invention takes the torque generated by the wind load as the design input, simulates on land, and loads with tooling and counterweights to prove the capabilities of the rotating motor, slewing bearing and supporting structure, and proposes a method for obtaining the counterweight for the rotation test in the land-based test of the sail.

[0005] In order to achieve the above object, the present invention provides a method for obtaining a counterweight for a rotation test in a land-based test of a large sail, comprising the following steps:

[0006] S1, determine the composition of the system in the rotation test, including the slewing bearing S, which is driven by the motor to rotate, and the slewing bearing drives the sail to rotate; A is a strap, one end of which is tied to the slewing bearing S, and the other end is connected to the movable pulley C of the counterweight fixture; B is the counterweight fixture, including the counterweight fixture body, and the movable pulley C and fixed pulley D connected by the wire rope H; E is the counterweight; one end of the wire rope H is connected to the body of the counterweight fixture B, and the other end is connected to the counterweight E through the movable pulley C and the fixed pulley D in turn;

[0007] S2. Obtaining weight

[0008]

[0009] F1 is the counterweight to be obtained, F is the couple acting on the slewing bearing S, that is, the strap is subjected to the traction force of the counterweight; μ is the friction coefficient between the fixed pulley and the movable pulley; α is the angle between F2 and F3, F2 is the tension of the wire rope between the movable pulley and the fixed pulley; F3 is the tension of the wire rope between the movable pulley and the tooling body; R is the radius of the slewing bearing; the torque M1 is applied to the sail.

[0010] In a special mode, the counterweight fixture is not provided with a movable pulley C, so the counterweight is:

[0011]

[0012] In the preferred mode, the slewing bearing S rotates counterclockwise. The rotation ability of the sail needs to be examined under the working conditions: under the torque load with the maximum design wind speed, one end of the strap is connected to the slewing bearing, and the other end is connected to the counterweight fixture. The design of the couple is completed through the counterweight fixture to examine the rotation ability of the sail. The torque borne by the sail during operation is obtained by numerical calculation or wind tunnel test to obtain the load M1 of the sail.

[0013] In addition, the counterweight tooling B is provided in one group or two symmetrical groups, or multiple groups arranged symmetrically in the center.

[0014] In order to verify the rotation system capability of the sail, the present invention simulates the maximum torsional load of the sail in actual ship operation on land, and at the same time considers the loading condition of the tooling to form a weight calculation method for the rotation test, thereby ensuring the smooth implementation of the rotation test.

[0015] The present invention completes the simulated load of the rotation test in the form of a force couple and meets the functional test requirements; the present invention designs a counterweight fixture through a combination of a fixed pulley and a movable pulley, which can reduce the size of the counterweight and facilitate the test; the present invention takes into account the mechanical properties of the test fixture itself and can quickly complete the counterweight acquisition of the rotation test. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the composition of the rotating system and tooling;

[0017] Figure 2 Figure 1 Schematic diagram of the top view of the mid-XX rotation system;

[0018] Figure 3 yes Figure 2 Side schematic diagram of the YY-axis counterweight tooling. DETAILED DESCRIPTION

[0019] Figure 1 The figure is a schematic diagram of the rotating system. S is a slewing bearing, which is driven by a motor to rotate and drives the sail to rotate; A is a strap, one end of which is tied to the slewing bearing S and the other end is connected to the movable pulley C of the counterweight fixture; B is the counterweight fixture, including the counterweight fixture body, movable pulley C, and fixed pulley D; E is the counterweight; H is a wire rope, one end of which is connected to the body of the counterweight fixture B and the other end is connected to the counterweight E through the movable pulley C and the fixed pulley D, which can make the counterweight lighter and easier to carry out the test.

[0020] Figure 2The top view of the rotating system is shown in Figure XX. S is a slewing bearing with a radius of R, which rotates counterclockwise (such as N); A is a strap, which is subjected to a counterweight traction force F to simulate the torque; and B is a counterweight fixture.

[0021] Figure 3 The figure is a side view of the counterweight tooling "YY". C is a movable pulley; D is a fixed pulley; H is a wire rope, which is divided into three parts: the first part is the part between the movable pulley and the fixed pulley, the second part is the part between the movable pulley and the tooling body, and the third part is the part between the fixed pulley and the counterweight; F is the tension provided by the rotation of the slewing bearing through the strap; F1 is the downward tension provided by the counterweight, acting on the third part of the wire rope H (the part between the fixed pulley and the counterweight); F2 is the tension acting on the first part of the wire rope (the part between the movable pulley and the fixed pulley); F3 is the tension acting on the second part of the wire rope (the part between the movable pulley and the tooling body); the angle between F2 and F3 is α.

[0022] The mechanical system of a sail consists of a slewing base, a mast, and a sail surface. Since the mast is connected to the slewing base by bolts and the motor drives the slewing bearing to rotate, the sail's rotation ability is mainly determined by the motor's ability. In actual use, the wind load is transmitted to the mast through the sail surface, and the mast is then transmitted to the base. The motor needs to overcome the torque caused by the uneven wind load on the sail surface. In the rotation test of the land-based test, the above load is mainly simulated by the force couple acting on the slewing bearing to examine whether the motor can rotate smoothly under the simulated load.

[0023] In the process of simulating the above loads, in order to reduce the counterweight and facilitate the completion of the experiment, the counterweight fixture is designed through the combination of a fixed pulley and a movable pulley. It is necessary to consider the mechanical properties of the test fixture itself and the friction between the components to calculate the final counterweight.

[0024] First, the sail booster system rotation test conditions are described

[0025] The rotation ability of the sail needs to be examined under a working condition, that is, under the torque load with the maximum design wind speed, one end of the strap is connected to the slewing bearing, and the other end is connected to the counterweight fixture. The design of the couple is completed through the counterweight fixture to examine the rotation ability of the sail.

[0026] 1) Torque on the sail under normal operation

[0027] The torque acting on the sail comes entirely from the wind load, which is related to the cross-sectional airfoil of the sail. The load acting on the sail can be obtained through numerical calculation or wind tunnel test, where the torque value is M1.

[0028] 2) Load simulated by the rotation test

[0029] Figure 1 The figure is a schematic diagram of the rotating system. S is a slewing bearing, which is driven by a motor to rotate and drives the sail to rotate; A is a strap, one end of which is tied to the slewing bearing S and the other end is connected to the movable pulley C of the counterweight fixture; B is the counterweight fixture, including the counterweight fixture body, movable pulley C, and fixed pulley D; E is the counterweight; H is a wire rope, one end of which is connected to the body of the counterweight fixture B and the other end is connected to the counterweight E through the movable pulley C and the fixed pulley D, which can make the counterweight lighter and easier to carry out the test.

[0030] Figure 2 The top view of the rotating system is shown in Figure XX. S is a slewing bearing with a radius of R, which rotates counterclockwise (such as N); A is a strap, which is subjected to a counterweight traction force F to simulate the torque; and B is a counterweight fixture.

[0031] Figure 3 The figure is a side view of the counterweight tooling "YY". C is a movable pulley; D is a fixed pulley; H is a wire rope, which is divided into three parts: the first part is the part between the movable pulley and the fixed pulley, the second part is the part between the movable pulley and the tooling body, and the third part is the part between the fixed pulley and the counterweight; F is the tension provided by the rotation of the slewing bearing through the strap; F1 is the downward tension provided by the counterweight, acting on the third part of the wire rope H (the part between the fixed pulley and the counterweight); F2 is the tension acting on the first part of the wire rope (the part between the movable pulley and the fixed pulley); F3 is the tension acting on the second part of the wire rope (the part between the movable pulley and the tooling body); the angle between F2 and F3 is α.

[0032] like Figure 3 As shown, F1 is the counterweight to be calculated, and F is one of the couples acting on the slewing bearing S. If the relationship between F1 and F is obtained, F1 can be calculated. In the figure, F1, F2 and F3 are all on the same wire rope, and due to the setting of the fixed pulley and the movable pulley, friction will be generated, resulting in different forces in each section. Here, the friction coefficient of the fixed pulley and the movable pulley is the same, denoted as μ. In the process of calculating F1, the relationship between F1 and F2 must be calculated first, and then the relationship between F2 and F3 must be calculated. Then, through the relationship between F and F2 and F3, the relationship coefficient between F1 and F is obtained, and then the final F1, that is, the counterweight, is determined through the calculation of the couple.

[0033] ①Relationship between F2 and F1:

[0034] like Figure 3 As shown, there is a fixed pulley D between F2 and F1. Considering the friction coefficient μ of the fixed pulley, we have:

[0035] F2=[(1+(1-(1-μ 2 ) 2 ) 0.5) / (1-μ 2 )]F1 (1)

[0036] ②Relationship between F3 and F2:

[0037] like Figure 3 As shown, there is a movable pulley C between F3 and F2. Considering the friction coefficient μ of the movable pulley, we have:

[0038] F3=[((1+μ 2 cosα)+((1+μ 2 cosα) 2 -(1-μ 2 ) 2 ) 0.5 ) / (1-μ 2 )]F2 (2)

[0039] ③The relationship between F, F2 and F3:

[0040] Since the force on F is the projection of F3 and F2 in the horizontal direction, we have:

[0041] F=F2+F3cosα (3)

[0042] ④The relationship between F and F1:

[0043] From formula (1), formula (2) and formula (3), we can get:

[0044] F=Δ·F1 (4)

[0045] in

[0046] ⑤Calculation of counterweight F1:

[0047] The relationship between torque, slewing bearing radius and couple is as follows:

[0048] M1=F×R

[0049] From formula (4), we can get:

[0050]

[0051] From formula (5), we can get:

[0052]

[0053] If the counterweight fixture is not equipped with a movable pulley C, that is, F3 = 0, then the calculation formula for the counterweight F1 is:

[0054]

[0055] In summary, the load of the sail in the rotation test can be determined, and the subsequent counterweight calculation can be further improved according to the mechanical characteristics of the sail tooling.

[0056] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for obtaining counterweight for a rotation test in a land-based test of a large sail, characterized in that: The steps include: S1, determine the composition of the system in the rotation test, including the slewing bearing S, which is driven by the motor to rotate, and the slewing bearing drives the sail to rotate; A is a strap, one end of which is tied to the slewing bearing S, and the other end is connected to the movable pulley C of the counterweight fixture; B is the counterweight fixture, including the counterweight fixture body, and the movable pulley C and fixed pulley D connected by the wire rope H; E is the counterweight; one end of the wire rope H is connected to the body of the counterweight fixture B, and the other end is connected to the counterweight E through the movable pulley C and the fixed pulley D in turn; S2. Get the weight F1 is the counterweight to be obtained, F is the force couple acting on the slewing bearing S, that is, the traction force of the counterweight is applied to the strap; μ is the friction coefficient between the fixed pulley and the movable pulley; α is the angle between F2 and F3, and F2 is the tension of the wire rope acting between the movable pulley and the fixed pulley; F3 is the tension of the wire rope acting between the movable pulley and the tooling body; R is the radius of the slewing bearing; and M1 is the torque applied to the sail.

2. The method for obtaining the counterweight of the rotation test in the land-based test of a large sail according to claim 1, characterized in that: If the counterweight fixture is not equipped with a movable pulley C, the counterweight is:

3. The method for obtaining the counterweight of the rotation test in the land-based test of a large sail according to claim 1, characterized in that: The slewing bearing S rotates counterclockwise.

4. The method for obtaining the counterweight of the rotation test in the land-based test of a large sail according to claim 1, characterized in that: The rotation ability of the sail needs to be examined under the working conditions: under the torque load with the maximum design wind speed, one end of the strap is connected to the slewing bearing, and the other end is connected to the counterweight fixture. The design of the couple is completed through the counterweight fixture to examine the rotation ability of the sail.

5. The method for obtaining the counterweight of the rotation test in the land-based test of a large sail according to claim 1, characterized in that: The torque on the sail during operation is obtained by numerical calculation or wind tunnel test to obtain the load M1 on the sail.

6. The method for obtaining the counterweight of the rotation test in the land-based test of a large sail according to claim 1, characterized in that: The counterweight tooling B is a set.

7. The method for obtaining the counterweight of the rotation test in the land-based test of a large sail according to claim 1, characterized in that: The counterweight fixtures B are divided into two symmetrical groups.

8. The method for obtaining the counterweight of the rotation test in the land-based test of a large sail according to claim 1, characterized in that: The counterweight fixtures B are multiple groups arranged symmetrically around the center.

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