A segmented trimaran model and a wave load measurement method

Abstract

A segmented trimaran model and a wave load measurement method, characterized in that: comprising a main hull and a piece body located on both sides of the main hull, the main hull is divided into N segments along the length direction, N is greater than or equal to four, each segment of the main hull is connected through the longitudinal measuring beam arranged along the length direction, the longitudinal measuring beam is provided with a first transverse measuring beam and a second transverse measuring beam; each piece body is divided into two segments; the two ends of the first transverse measuring beam are respectively connected with the front piece body; the two ends of the second transverse measuring beam are respectively connected with the rear piece body; the main hull, the connecting bridge and the piece body between the first transverse measuring beam and the second transverse measuring beam are segmented at the same station; the connecting bridge between the piece body and the main hull is segmented, and the segmented position is the longitudinal segmented position and penetrates through the whole connecting bridge along the length direction. Thus, the load borne by the main hull and the connecting bridge can be accurately measured simultaneously during the wave load test.

Description

Technical Field

[0001] This invention relates to the field of wave load testing and measurement technology for ship models, and in particular to a segmented trimaran model and a method for measuring wave load. Background Technology

[0002] Due to their excellent stability and seakeeping performance, as well as their large deck area, trimarans are increasingly being designed and built, playing a vital role in social development. However, because trimarans have high speeds and may need to perform special missions in harsh sea conditions, they are subject to significant wave loads, posing a significant threat to the structural strength of the hull. Furthermore, due to the unique hull shape of trimarans, their wave load characteristics are more complex and difficult to determine compared to traditional monohull vessels. Therefore, wave load testing using ship models is the most effective and reliable method for studying the wave load characteristics of trimarans.

[0003] However, due to its unique hull and connecting bridge structure, the stress situation of trimarans in waves is very complex. Stress analysis and load tests on the connecting bridge are important means to evaluate the performance of trimarans. More accurate trimaran models and wave load measurement methods that reflect the stress on the connecting bridge and the main hull are needed. Summary of the Invention

[0004] To address the shortcomings of existing production technologies, the applicant provides a segmented trimaran model and a wave load measurement method, thereby enabling simultaneous and accurate measurement of the loads on the main hull and connecting bridge during wave load testing.

[0005] The technical solution adopted in this invention is as follows:

[0006] A segmented trimaran model includes a main hull and two side panels located on both sides of the main hull, the main hull and the side panels being connected by a connecting bridge;

[0007] The main hull is divided into N sections along the length of the ship, where N is greater than or equal to four. The sections of the main hull are connected by longitudinal measuring beams set along the length of the ship. A first transverse measuring beam and a second transverse measuring beam are installed on the longitudinal measuring beams.

[0008] Each piece is divided into two segments: a forward piece located in the bow direction and a rear piece located in the stern direction. The break between the forward and rear pieces is the segmentation point of the piece.

[0009] The first transverse measuring beam is perpendicular to the longitudinal measuring beam, and the two ends of the first transverse measuring beam are respectively connected to the front plate.

[0010] The second transverse measuring beam is perpendicular to the longitudinal measuring beam, and the two ends of the second transverse measuring beam are respectively connected to the rear plate.

[0011] The main hull and connecting bridge are segmented between the first transverse measuring beam and the second transverse measuring beam. The segmentation location is at the segmentation point between the transverse beams, and the station position at the segmentation point between the transverse beams is the same as that at the segmentation point of the sheet body.

[0012] The connecting bridge between the sheet body and the main hull is segmented, with the segmentation location being the longitudinal segmentation point and running through the entire connecting bridge along the length of the ship.

[0013] The distance between the first transverse measuring beam and the segment between the beams is:

[0014] The distance between the second transverse measuring beam and the segment between the beams is [value missing].

[0015] Its further technical solution lies in:

[0016] The longitudinal segment and the segment between the crossbeam are arranged in a cross shape.

[0017] As described in claim 1, a segmented trimaran model is provided, wherein strain sensors are installed on the first and second transverse measuring beams at the longitudinal segment, and strain sensors are installed on the longitudinal measuring beam (d) at the main hull segment.

[0018] The strain sensor is a strain gauge.

[0019] In the segmented trimaran model as described in claim 1, the first transverse measuring beam and the second transverse measuring beam have the same cross-sectional dimensions.

[0020] The first and second transverse measuring beams and the longitudinal measuring beam are all steel round tubes. The longitudinal measuring beam is provided with a round hole that matches the outer diameter of the first and second transverse measuring beams. After the first and second transverse measuring beams are inserted into the round hole, they are welded to the longitudinal measuring beam respectively.

[0021] The sections of the main hull, the hull sheet, and the connecting bridge are sealed with rubber films.

[0022] A method for measuring wave loads on a segmented trimaran model includes the following steps:

[0023] Install strain sensors:

[0024] Strain gauges are attached to the outer surface of the longitudinal measuring beam at the main hull section location, and strain gauges are attached to the outer surface of the first transverse measuring beam at the longitudinal section to measure the vertical bending moment, vertical shear force, and torque borne by the first transverse measuring beam at the longitudinal section. Strain gauges are attached to the outer surface of the second transverse measuring beam at the longitudinal section to measure the vertical bending moment, vertical shear force, and torque borne by the second transverse measuring beam at the longitudinal section.

[0025] Wave resistance test in a water tank: After connecting the strain gauges to the signal acquisition system, the strain signals of the trimaran model are collected when it sails in waves. The strain signals are then converted into vertical bending moment, vertical shear force, and torque by the data processing system.

[0026] Data processing: The vertical bending moment, vertical shear force, and torque data of the first and second transverse measuring beams are processed to obtain the total load borne by the connecting bridge.

[0027] Its further technical solution lies in:

[0028] During the wave resistance test in the water tank, the data output by the data processing system includes:

[0029] The vertical bending moments borne by the first transverse measuring beam at the two longitudinal segments on the left and right are MV4 and MV5, respectively.

[0030] The vertical shear forces borne by the first transverse measuring beam at the two longitudinal segments on the left and right are FV4 and FV5, respectively.

[0031] The torques borne by the first transverse measuring beam at the two longitudinal segments on the left and right are T4 and T5, respectively.

[0032] The vertical bending moments borne by the second transverse measuring beams corresponding to the two longitudinal segments on the left and right are MV6 and MV7, respectively.

[0033] The vertical shear forces borne by the second transverse measuring beams corresponding to the two longitudinal segments on the left and right are FV6 and FV7, respectively.

[0034] The torques borne by the second transverse measuring beams corresponding to the two longitudinal segments on the left and right are T6 and T7, respectively.

[0035] During data processing:

[0036] The vertical bending moment, vertical shear force, and torque borne by the connecting bridge (c) on the left are expressed as follows:

[0037] MV8 = MV4 + MV6 (1)

[0038] FV8=FV4+FV6 (2)

[0039] T8=FV6l2-FV4l1+T4+T6 (3)

[0040] The vertical bending moment, vertical shear force, and torque borne by the connecting bridge (c) on the right are expressed as follows:

[0041] MV9 = MV5 + MV7 (4)

[0042] FV9=FV5+FV7 (5)

[0043] T9=FV7l2-FV5l1+T5+T7 (6).

[0044] The beneficial effects of this invention are as follows:

[0045] This invention features a compact and reasonable structure and is easy to operate. By using a double cross measuring beam to connect the segmented panels to the main hull and segmenting the connecting bridge along the transverse and longitudinal directions, all the loads borne by the panels and the main hull are transferred to the double cross measuring beam, thereby enabling simultaneous and accurate measurement of the loads on the main hull and the connecting bridge during wave load testing.

[0046] By dividing the body and connecting bridge into segments, the loads borne by the two transverse measuring beams are measured separately, and then the loads are added together to obtain the load on a single connecting bridge. During the stress measurement of the connecting bridge, the stress deformation of the two transverse measuring beams and the deformation of the main hull are simultaneously linked, making the measured wave loads more comprehensive and better reflecting the overall structural characteristics of the trimaran model. Attached Figure Description

[0047] Figure 1 This is a schematic diagram (top view) of the structure of the present invention.

[0048] Figure 2 This is a schematic diagram (side view) of the structure of the present invention.

[0049] Figure 3 This is a schematic diagram (cross-sectional view) of the structure of the present invention.

[0050] Figure 4 This is a schematic diagram of the measuring beam of the present invention.

[0051] Wherein: a, main hull; b, hull section; b1, forward hull section; b2, aft hull section; c, connecting bridge; d, longitudinal measuring beam; e, first transverse measuring beam; f, second transverse measuring beam; g, first support beam; h, second support beam;

[0052] M0, section segment; M1, first section segment of main hull; M2, second section segment of main hull; M3, section segment between beams. Detailed Implementation

[0053] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0054] Example 1:

[0055] like Figures 1-4 As shown, the segmented trimaran model of this embodiment includes a main hull a and two hulls b located on both sides of the main hull a. The main hull a and the hull b are connected by a connecting bridge c.

[0056] The main hull a is divided into N sections along the length of the ship, where N is greater than or equal to four. The various sections of the main hull a are connected by longitudinal measuring beams d set along the length of the ship. The longitudinal measuring beams d are equipped with a first transverse measuring beam e and a second transverse measuring beam f.

[0057] Each piece b is divided into two segments: a forward piece b1 located in the bow direction and a rear piece b2 located in the stern direction. The break between the forward piece b1 and the rear piece b2 is the piece segmentation point M0. The first transverse measuring beam e is perpendicular to the longitudinal measuring beam d, and the two ends of the first transverse measuring beam e are connected to the forward piece b1. The second transverse measuring beam f is perpendicular to the longitudinal measuring beam d, and the two ends of the second transverse measuring beam f are connected to the rear piece b2.

[0058] Specifically, the first transverse measuring beam e, the second transverse measuring beam f, and the longitudinal measuring beam d are all made of steel. The first transverse measuring beam e, the second transverse measuring beam f, and the longitudinal measuring beam d are all rigidly connected, forming a double-cross measuring beam. The main hull a is made of fiberglass. Based on the ship's hull characteristics, the double-cross measuring beams are symmetrical about the port and starboard sides. The cross-sectional dimensions of the longitudinal measuring beam d are larger than those of the first transverse measuring beam e and the second transverse measuring beam f. The longitudinal measuring beam d, the first transverse measuring beam e, and the second transverse measuring beam f are on the same horizontal plane and fixedly connected at their intersections. Each section of the main hull a is provided with at least two first support beams g for connection to the longitudinal measuring beam d. The forward section b1 and the aft section b2 are respectively provided with second support beams h with wider cross-sections for connection to the transverse measuring beams. Typically, the support beams are connected to the measuring beams via supports, such as... Figure 3 As shown; the first support beam g and the second support beam h are usually made of wood.

[0059] The main hull a and connecting bridge c are separated between the first transverse measuring beam e and the second transverse measuring beam f. The segmentation location is M3 between the transverse beams. The positions of M3 between the transverse beams and M0 between the sheet body segments are the same. The connecting bridge c between the sheet body b and the main hull a is also separated. The segmentation location is at the longitudinal segmentation and runs through the entire connecting bridge c along the length of the ship.

[0060] The distance between the first transverse measuring beam e and the segment M3 between the beams is l1;

[0061] The distance between the second transverse measuring beam f and the segment M3 between the beam and the crossbeam is l2.

[0062] Rubber films are affixed to the sections of the main hull (a), hull (b), and connecting bridge (c) for sealing.

[0063] Specifically, the longitudinal segment is located at the midpoint of the transverse direction of the connecting bridge c, and the sum of l1 and l2 is the distance between the first transverse measuring beam e and the second transverse measuring beam f; for example... Figure 1As shown, the section M3 between the crossbeams and the section M0 between the sheet sections form a cross section that runs through the trimaran model, ensuring the consistency of the sections between sheet b and the main hull a. The sections M3 between the crossbeams and the longitudinal sections separate the connecting bridge c in both the transverse and longitudinal directions, ensuring that the separated local connecting bridge is connected to the main hull a and sheet b. This allows it to withstand wave loads and transfer them to the double cross measuring beam, ensuring that the double cross measuring beam can accurately reflect the structural characteristics of the trimaran.

[0064] By using a double cross measuring beam to connect the segmented body b to the main hull a, and segmenting the connecting bridge c along the transverse and longitudinal directions, all the loads borne by body b and the main hull a are transferred to the double cross measuring beam, thereby enabling simultaneous and accurate measurement of the loads on the main hull a and the connecting bridge c during wave load testing.

[0065] like Figure 1 As shown, the longitudinal segment and the segment between the crossbeam M3 are in a cross shape.

[0066] Specifically, there are two cross-shaped intersections, located on the connecting bridges c on both sides of the main hull a. The length of M3 at the segment between the crossbeams extends through the width of the main hull a and then to the connecting bridge c until it ends on the outer side of the plate b.

[0067] In addition, strain sensors need to be installed on the first transverse measuring beam e and the second transverse measuring beam f at the longitudinal segment before measuring wave loads, and on the longitudinal measuring beam d at the main hull segment a. The strain sensors are strain gauges. Specifically, the strain gauges are attached to the outer surface of the measuring beams.

[0068] Preferably, the cross-sectional dimensions of the first transverse measuring beam e and the second transverse measuring beam f are the same.

[0069] Furthermore, the first transverse measuring beam e, the second transverse measuring beam f, and the longitudinal measuring beam d are all steel circular tubes. The longitudinal measuring beam d has circular holes matching the outer diameters of the first transverse measuring beam e and the second transverse measuring beam f. After the first transverse measuring beam e and the second transverse measuring beam f are inserted into the circular holes, they are welded to the longitudinal measuring beam d, respectively. Figure 3 As shown.

[0070] In the above structure, it is necessary to ensure that the first transverse measuring beam e and the second transverse measuring beam f are symmetrical about the longitudinal measuring beam d.

[0071] Example 2:

[0072] The wave load measurement method using the segmented trimaran model of Example 1 includes the following steps:

[0073] Install strain sensors:

[0074] Strain gauges are attached to the outer surface of the longitudinal measuring beam d at section a of the main hull, and strain gauges are attached to the outer surface of the first transverse measuring beam e at the longitudinal section to measure the vertical bending moment, vertical shear force, and torque borne by the first transverse measuring beam e at the longitudinal section. Strain gauges are attached to the outer surface of the second transverse measuring beam f at the longitudinal section to measure the vertical bending moment, vertical shear force, and torque borne by the second transverse measuring beam f at the longitudinal section.

[0075] Wave resistance test in a water tank: After connecting the strain gauges to the signal acquisition system, the strain signals of the trimaran model are collected when it sails in waves. The strain signals are then converted into vertical bending moment, vertical shear force, and torque by the data processing system.

[0076] In the wave resistance test tank, the data output by the data processing system includes:

[0077] The vertical bending moments borne by the first transverse measuring beam e corresponding to the two longitudinal segments on the left and right are MV4 and MV5, respectively.

[0078] The vertical shear forces borne by the first transverse measuring beam e corresponding to the two longitudinal segments on the left and right are FV4 and FV5, respectively.

[0079] The torques borne by the first transverse measuring beam e at the two longitudinal segments on the left and right are T4 and T5, respectively.

[0080] The vertical bending moments borne by the second transverse measuring beam f at the two longitudinal segments on the left and right are MV6 and MV7, respectively.

[0081] The vertical shear forces borne by the second transverse measuring beam f at the two longitudinal segments on the left and right are FV6 and FV7, respectively.

[0082] The torques borne by the second transverse measuring beam f at the two longitudinal segments on the left and right are T6 and T7, respectively.

[0083] In the wave-resistance tank test, the data processing system output data also includes:

[0084] The vertical bending moment, vertical shear force, and torque borne by the longitudinal measuring beam at position d at section a of the main hull.

[0085] Data processing: The vertical bending moment, vertical shear force, and torque data of the first transverse measuring beam e and the second transverse measuring beam f are processed to obtain the total load borne by the connecting bridge c.

[0086] During data processing:

[0087] The vertical bending moment, vertical shear force, and torque borne by the port-side connecting bridge c are expressed as follows:

[0088] MV8 = MV4 + MV6 (1)

[0089] FV8=FV4+FV6 (2)

[0090] T8=FV6l2-FV4l1+T4+T6 (3)

[0091] The vertical bending moment, vertical shear force, and torque borne by the connecting bridge c on the starboard side are expressed as follows:

[0092] MV9 = MV5 + MV7 (4)

[0093] FV9=FV5+FV7 (5)

[0094] T9=FV7l2-FV5l1+T5+T7 (6).

[0095] The wave load measurement method for the segmented trimaran model in this embodiment involves dividing the body b and the connecting bridge c into segments, measuring the loads borne by two transverse measuring beams separately, and then adding them together to obtain the load on a single connecting bridge c. During the stress measurement of the connecting bridge, the stress deformation of the two transverse measuring beams and the deformation of the main hull are simultaneously linked, making the measured wave load more comprehensive and better reflecting the overall structural characteristics of the trimaran model.

[0096] Example 3:

[0097] The wave load measurement methods for the segmented trimaran model in Example 1 and Example 2 are more suitable for trimaran with long hulls (the hulls extend from the stern to the middle of the ship), making the wave load measurement more accurate.

[0098] This embodiment uses a long hull trimaran as an example to introduce the segmentation of the trimaran model.

[0099] like Figure 1 As shown, the sections were cut at stations 5, 10, and 15, as well as at the connecting bridge c. Each section was 20mm apart and connected to a double cross steel measuring beam to form a whole. Rubber films were pasted on the sections for sealing. The cross sections are marked as M0, M1, M2, M3, M4, M5, M6, and M7 in the figure.

[0100] The segmentation point of sheet body b is M0;

[0101] The main hull a is divided into sections M1, M2 and M3 from bow to stern. M3 is the section between the beams and is located on the same cross section as M0.

[0102] The longitudinal section located on the left side of the main hull a is Figure 1 At points M4 and M6, the longitudinal segments located on the right side of the main hull a are points M5 and M7 in the diagram.

[0103] Strain sensors were placed on the measuring beam at points M1, M2, M3, M4, M5, M6, and M7 to obtain the strain in each direction of the trimaran model as it sails in waves. The wave loads borne by the main hull (a) and connecting bridge (c) were obtained, including vertical bending moment, horizontal bending moment, torque, vertical shear force, and horizontal shear force.

[0104] Let the vertical bending moments borne by the transverse measuring beam at sections M4, M5, M6, and M7 be defined as MV4, MV5, MV6, and MV7, the vertical shear forces as FV4, FV5, FV6, and FV7, and the torques as T4, T5, T6, and T7. Then, the total load borne by the connecting bridge c can be expressed as:

[0105] MV8 = MV4 + MV6

[0106] MV9 = MV5 + MV7

[0107] FV8 = FV4 + FV6

[0108] FV9 = FV5 + FV7

[0109] T8 = (FV6 - FV4)·l + T4 + T6

[0110] T9 = (FV7 - FV5) * l + T5 + T7

[0111] In the above formula, MV8, MV9, FV8, and FV9 represent the total vertical bending moment and total vertical shear force borne by the port and starboard connecting bridges c, respectively. T8 and T9 represent the total torque borne by the port and starboard connecting bridges c at station 5, respectively. l is the distance between the two transverse measuring beams and station 5, i.e., l1 and l2 are equal, both being l.

[0112] 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 scope of protection of the present invention, any form of modification may be made.

Claims

1. A segmented trimaran model, characterized in that: It includes a main hull (a) and sheet bodies (b) located on both sides of the main hull (a), the main hull (a) and the sheet bodies (b) being connected by a connecting bridge (c); The main hull (a) is divided into N sections along the length of the ship, where N is greater than or equal to four. The sections of the main hull (a) are connected by longitudinal measuring beams (d) set along the length of the ship. A first transverse measuring beam (e) and a second transverse measuring beam (f) are installed on the longitudinal measuring beams (d). Each piece (b) is divided into two segments: a forward piece (b1) in the bow direction and a rear piece (b2) in the stern direction. The break between the forward piece (b1) and the rear piece (b2) is the piece segmentation point (M0). The first transverse measuring beam (e) is perpendicular to the longitudinal measuring beam (d), and the two ends of the first transverse measuring beam (e) are respectively connected to the front piece (b1); The second transverse measuring beam (f) is perpendicular to the longitudinal measuring beam (d), and the two ends of the second transverse measuring beam (f) are respectively connected to the rear plate (b2); The main hull (a) and connecting bridge (c) between the first transverse measuring beam (e) and the second transverse measuring beam (f) are segmented, and the segmentation position is at the segmentation point between the transverse beams (M3). The position of the segmentation point between the transverse beams (M3) and the position of the segmentation point of the sheet body (M0) are the same. The connecting bridge (c) between the sheet (b) and the main hull (a) is segmented, with the segmentation location being at the longitudinal segmentation point and running through the entire connecting bridge (c) along the ship's length direction; The distance between the first transverse measuring beam (e) and the segment (M3) between the crossbeams is l1; the distance between the second transverse measuring beam (f) and the segment (M3) between the crossbeams is l2.

2. The segmented trimaran model as described in claim 1, characterized in that: The longitudinal segment and the segment between the crossbeam (M3) form a cross shape.

3. A segmented trimaran model as described in claim 1, characterized in that: Strain sensors are installed on the first transverse measuring beam (e) and the second transverse measuring beam (f) at the longitudinal segment, and strain sensors are installed on the longitudinal measuring beam (d) at the main hull (a) segment.

4. A segmented trimaran model as described in claim 3, characterized in that: The strain sensor is a strain gauge.

5. A segmented trimaran model as described in claim 1, characterized in that: The first transverse measuring beam (e) and the second transverse measuring beam (f) have the same cross-sectional dimensions.

6. A segmented trimaran model as described in claim 5, characterized in that: The first transverse measuring beam (e), the second transverse measuring beam (f), and the longitudinal measuring beam (d) are all steel round tubes. The longitudinal measuring beam (d) is provided with round holes that match the outer diameter of the first transverse measuring beam (e) and the second transverse measuring beam (f). After the first transverse measuring beam (e) and the second transverse measuring beam (f) are inserted into the round holes, they are respectively welded to the longitudinal measuring beam (d).

7. A segmented trimaran model as described in claim 1, characterized in that: Rubber films are affixed to the sections of the main hull (a), the sheet (b), and the connecting bridge (c) for sealing.

8. The wave load measurement method for a segmented trimaran model as described in claim 1, characterized in that: Includes the following steps: Install strain sensors: Strain gauges are attached to the outer surface of the longitudinal measuring beam (d) at the section location of the main hull (a), and strain gauges are attached to the outer surface of the first transverse measuring beam (e) at the longitudinal section to measure the vertical bending moment, vertical shear force, and torque borne by the first transverse measuring beam (e) at the longitudinal section. Strain gauges are attached to the outer surface of the second transverse measuring beam (f) at the longitudinal section to measure the vertical bending moment, vertical shear force, and torque borne by the second transverse measuring beam (f) at the longitudinal section. Wave resistance test in a water tank: After connecting the strain gauges to the signal acquisition system, the strain signals of the trimaran model are collected when it sails in waves. The strain signals are then converted into vertical bending moment, vertical shear force, and torque by the data processing system. Data processing: The vertical bending moment, vertical shear force, and torque data of the first transverse measuring beam (e) and the second transverse measuring beam (f) are processed to obtain the total load borne by the connecting bridge (c).

9. The wave load measurement method for a segmented trimaran model as described in claim 8, characterized in that: During the wave resistance test in the water tank, the data output by the data processing system includes: The vertical bending moments borne by the first transverse measuring beam (e) corresponding to the two longitudinal segments on the left and right are MV4 and MV5, respectively. The vertical shear forces borne by the first transverse measuring beam (e) corresponding to the two longitudinal segments on the left and right are FV4 and FV5, respectively. The torques borne by the first transverse measuring beam (e) corresponding to the two longitudinal segments on the left and right are T4 and T5, respectively. The vertical bending moments borne by the second transverse measuring beam (f) corresponding to the two longitudinal segments on the left and right are MV6 and MV7, respectively. The vertical shear forces borne by the second transverse measuring beam (f) corresponding to the two longitudinal segments on the left and right are FV6 and FV7, respectively. The torques borne by the second transverse measuring beam (f) corresponding to the two longitudinal segments on the left and right are T6 and T7, respectively. During data processing: The vertical bending moment, vertical shear force, and torque borne by the connecting bridge (c) on the left are expressed as follows: MV8 = MV4 + MV6 (1) FV8=FV4+FV6 (2) T8=FV6l2-FV4l1+T4+T6 (3) The vertical bending moment, vertical shear force, and torque borne by the connecting bridge (c) on the right are expressed as follows: MV9 = MV5 + MV7 (4) FV9=FV5+FV7 (5) T9=FV7l2-FV5l1+T5+T7 (6).

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