A ship statistical energy model modeling method, a computer storage medium and equipment

Abstract

The application relates to the technical field of ships, in particular to a ship statistical energy model modeling method, a computer storage medium and equipment. In the ship statistical energy model modeling method, plate shell elements are converted into statistical energy models with statistical energy model attribute information, then the converted subsystems are exported as a whole, and are imported into acoustic software as a whole, so that the subsystems of the finite element model do not need to be imported into the acoustic software one by one and statistical energy model attribute information does not need to be input in the acoustic software, the operation process is simplified, and the modeling efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ships, in particular to a ship statistical energy modeling method, a computer storage medium and equipment. BACKGROUND

[0002] The description in this part only provides background information related to the present disclosure and can not constitute prior art.

[0003] With the continuous development of the ship industry, safety and speed can no longer meet people's requirements, and how to obtain a comfortable living and working environment on the ship is increasingly concerned. With the promulgation and implementation of IMO MSC337(91), the requirements for ship cabin noise control are continuously improved. Therefore, how to accurately evaluate the cabin noise in ship design has become an important issue. Cabin noise evaluation often uses statistical energy method, and ship statistical energy modeling is one of the important links. The traditional modeling method is carried out in acoustic software, which needs to be carried out according to the ship drawings for a long time, far less efficient than finite element modeling software, resulting in a lag in the cabin noise evaluation result. In order to accurately evaluate the cabin noise level in the design stage, how to more quickly and accurately carry out ship statistical energy modeling will greatly affect the ship design and construction period.

[0004] At present, ship statistical energy modeling usually uses finite element modeling software for rapid modeling. The modeling method is to import a three-dimensional structure model into finite element modeling software, then clean the three-dimensional structure model and perform mesh division, then establish attribute information and number for different finite element model subsystems one by one, then export a file that can be recognized by acoustic software, then in the acoustic software, frame select the elements with consistent attributes in each finite element model subsystem and convert them into statistical energy models, and finally copy each statistical energy model to the window of the whole ship to complete the statistical energy model of the whole ship. Although this method can shorten the shipbuilding period, because the ship model has a large number of parts and the finite element model subsystems are numerous, the operation of exporting the finite element model subsystems and the operation of converting the finite element model subsystems into statistical energy models need to be performed by the operator one by one, which is tedious and time-consuming, and finally leads to the technical problem of low efficiency of ship statistical energy modeling. SUMMARY

[0005] The purpose of the embodiments of the present application is to provide a ship statistical energy modeling method for improving the efficiency of ship statistical energy modeling.

[0006] Another purpose of the embodiments of the present application is to provide a computer storage medium for implementing the above method.

[0007] Another purpose of the embodiments of the present application is to provide a computer storage device for implementing the above method.

[0008] In a first aspect, a ship statistical energy model modeling method is provided, comprising the following steps:

[0009] 1) importing a full-ship finite element model containing plate shell elements into a finite element modeling software;

[0010] 2) traversing each cabin to be detected in the full-ship finite element model, and making each cabin to be detected in a closed state;

[0011] 3) screening the plate shell elements according to preset conditions, and classifying each plate shell element meeting the screening conditions into a uniform plate subsystem;

[0012] 4) judging whether the screened uniform plate subsystem contains beam elements, marking and converting the uniform plate subsystem containing beam elements into a beam-plate statistical energy model containing statistical energy model attribute information, and marking and converting the uniform plate subsystem not containing beam elements into a uniform plate statistical energy model;

[0013] 5) exporting the beam-plate statistical energy model and the uniform plate statistical energy model from the finite element modeling software to an acoustic software;

[0014] 6) generating a sound cavity statistical energy model for each cabin to be detected in the acoustic software;

[0015] 7) establishing an energy transmission relationship among the beam-plate statistical energy model, the uniform plate statistical energy model, and the sound cavity statistical energy model, and forming a ship statistical energy model.

[0016] In a possible implementation, in steps 3) and 4), a statistical energy model conversion plug-in is applied to the plate shell elements in the finite element modeling software PATRAN for screening and conversion operations.

[0017] In a possible implementation, in step 5), after the beam-plate statistical energy model and the uniform plate statistical energy model are exported from the finite element modeling software and imported into the acoustic software, a beam-column statistical energy model for simulating a column in a cabin of the ship is established in the acoustic software according to a structure of the ship.

[0018] In a possible implementation, in step 5), whether the connection of each statistical energy model meets the requirements is checked in the acoustic software, and if not, the full-ship finite element model is processed again in step 2).

[0019] In a possible implementation, in step 5), the beam-plate statistical energy model and the uniform plate statistical energy model are exported in an xml format as a whole, and then imported into the acoustic software.

[0020] In a possible implementation, in step 1), according to the noise assessment requirements, the to-be-detected cabin that needs to be detected by multiple noise detection points in the noise detection is divided into multiple separated cabins by the self-defined panel unit, so that only one noise detection point is arranged in each separated cabin for detection.

[0021] In a possible implementation, in step 5), after the acoustic cavity statistical energy model corresponding to each separated cabin is generated in the acoustic software, the statistical energy model converted by the self-defined panel unit is deleted.

[0022] In a second aspect, a computer storage medium for implementing the method in any of the embodiments of the first aspect is provided, and the computer storage medium stores a computer program, which, when executed by a processor, implements the ship statistical energy model modeling method in any of the embodiments of the first aspect.

[0023] In a third aspect, a computer storage device for implementing the method in any of the embodiments of the first aspect is provided, and the computer storage device includes a memory and a processor, and the memory stores a computer program, which, when executed by the processor, implements the ship statistical energy model modeling method in any of the embodiments of the first aspect.

[0024] The ship statistical energy model modeling method has the beneficial effects that in the present application, the panel unit is converted into a statistical energy model with statistical energy model attribute information in the finite element model, and then the converted statistical energy models are exported and imported into the acoustic software as a whole, so that it is no longer necessary to import the subsystems of the finite element model into the acoustic software one by one and input the statistical energy model attribute information in the acoustic software, thereby simplifying the operation process and improving the modeling efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be considered as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0026] Figure 1 The basic flow of a ship statistical energy model modeling method according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0027] To make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0029] According to an aspect of the present application, a ship statistical energy model modeling method is first provided. For a large LNG ship, a full-ship finite element model is established based on vibration analysis, and statistical energy modeling is performed on the upper building area. Figure 1 A flowchart of a ship statistical energy model modeling method according to an embodiment of the present application is shown.

[0030] The ship statistical energy model modeling method includes the following steps:

[0031] 1) Importing the full-ship finite element model containing plate-shell elements into a finite element modeling software;

[0032] 2) Traversing the to-be-detected cabins in the full-ship finite element model, and making each of the to-be-detected cabins in a closed state;

[0033] 3) Screening the plate-shell elements according to a preset condition, and classifying each plate-shell element meeting the screening condition into a uniform plate subsystem;

[0034] 4) Judging whether the screened uniform plate subsystem contains beam elements, marking and converting the uniform plate subsystem containing beam elements into a beam-plate statistical energy model containing statistical energy model attribute information, and marking and converting the uniform plate subsystem not containing beam elements into a uniform plate statistical energy model;

[0035] 5) Integrally exporting the beam-plate statistical energy model and the uniform plate statistical energy model from the finite element simulation software to an acoustic software;

[0036] 6) Generating an acoustic cavity statistical energy model for each to-be-detected cabin in the acoustic software;

[0037] 7) Establishing an energy transmission relationship among the beam-plate statistical energy model, the uniform plate statistical energy model, and the acoustic cavity statistical energy model, and forming a ship statistical energy model.

[0038] In this application, a plate and shell element refers to multiple model elements that make up a single part in a finite element model, and each part is composed of multiple plate and shell elements.

[0039] The main task of organizing the finite element model of the entire ship involves filling in openings in areas such as doors and windows. For openings in areas such as doors and windows, the shell element groups in the corresponding regions are identified, and custom shell elements are used to fill the openings in the corresponding groups. Specifically, the custom shell element used to fill the opening is named the "Filling Shell Element," and corresponding information such as material, thickness, and sealing is established.

[0040] After the finite element model of the entire ship is designed, secondary bulkheads within the cargo hold are typically not built to separate the cargo hold during finite element modeling because they are essentially non-load-bearing. To improve noise detection accuracy, this embodiment separates the cargo hold into compartments to be tested. In one embodiment, simulating the actual ship structure, a bulkhead shell element with properties consistent with the actual structure is defined, and this element is used as the secondary bulkhead to separate the cargo hold into the compartments to be tested. The secondary bulkheads actually exist in the ship structure and do not need to be deleted later.

[0041] In the modeling method of this application, the finite element model of the entire ship is imported into finite element modeling software. Within the finite element modeling software, the uniform plate subsystem is transformed into a statistical energy model with statistical energy model attribute information. Each statistical energy model is then directly exported as a whole and imported into acoustic software. The acoustic software can recognize each statistical energy model and then generate acoustic cavity statistical energy models for each enclosed space. Energy transfer connections are established between the uniform plate statistical energy model, the acoustic cavity statistical energy model, and the stiffener statistical energy model to form the ship's statistical energy model. During the modeling process, it is unnecessary to export each part composed of plate and shell elements individually, nor is it necessary to add statistical energy model attribute information to the finite element model in the acoustic software to construct the statistical energy model, thus improving the modeling efficiency of the ship's statistical energy model.

[0042] In one embodiment, in step 1), according to the noise assessment requirements, the compartment to be tested, which is detected by multiple noise detection points during noise detection, is divided into multiple compartments using a custom-defined partition shell unit, so that only one noise detection point is set in each compartment. In one embodiment, the partition shell unit is a 2D shell unit. Specifically, according to the parameters of the partition shell unit, corresponding attribute information is established and named; according to the compartment layout diagram, the compartments are separated at corresponding positions using partition shell units; specifically, some larger compartments to be tested, such as the chart area and radio area in the bridge, need to be separated.

[0043] Since the partition shell units and filling shell units do not exist in the ship structure, in order to improve the accuracy of noise measurement and avoid the influence of the statistical energy models corresponding to the partition shell units and filling shell units on the test results, in step 6), after generating the acoustic cavity statistical energy models corresponding one-to-one with each partition compartment in the acoustic software, the statistical energy models converted from the partition shell units and filling shell units are deleted. The partition shell units and filling shell units are only used for partitioning the acoustic cavity statistical energy model in the statistical energy model and do not actually exist; deleting them makes the noise measurement values ​​closer to the actual situation.

[0044] In step 2), for the shell units surrounding the compartment and the assessment area, check the sealing condition to ensure that all form enclosed spaces. One embodiment is to use the Tool-edges function in the finite element modeling software Hypermesh to find free edges and make local modifications to the free edge regions.

[0045] In one embodiment, in steps 3) and 4), a statistical energy model conversion plugin is used in the finite element modeling software PATRAN to perform screening and conversion operations on the plate and shell elements. In this embodiment, the statistical energy model conversion plugin uses the PreSEA plugin, which can quickly construct the properties of plate and shell elements. Specifically, the PreSEA plugin is used to search and group based on the properties of the plate and shell elements. After grouping, multiple uniform plate subsystems are formed. The "Get Element Properties" option is checked, and a uniform plate statistical energy model is created for the uniform plate subsystems that do not contain stiffened beam elements. The properties of each plate and shell element in the uniform plate statistical energy model meet the screening requirements, and the plate and shell elements form a continuous whole; the uniform plate system containing stiffened beam elements is created as a stiffened plate statistical energy model.

[0046] In one embodiment, in step 5), after exporting the ribbed plate statistical energy model and the uniform plate statistical energy model from the finite element simulation software and importing them into the acoustic software, a beam-column statistical energy model for simulating the supports inside the ship's cabin is established in the acoustic software according to the ship's structure. The beam-column statistical energy model can improve the sensitivity and measurement accuracy of low-frequency noise detection. For cabins to be tested equipped with instruments sensitive to low-frequency noise, this design, once the noise detection is passed, can improve the stability of the instruments operating inside the cabin.

[0047] In one embodiment, in step 5), the connection of each statistical energy model is checked in the acoustic software to ensure it meets the requirements. If it does not, the process proceeds to step 2) to process the entire ship's finite element model again. One embodiment involves using the Free Edges function in the acoustic software VAOne to check the connection between adjacent statistical energy models in the uniform plate statistical energy model and the stiffener plate statistical energy model, ensuring that no free edges exist in any compartments or areas that should be enclosed; if free edges exist, the process proceeds to step 2). In another embodiment, if free edges exist in compartments or areas that should be enclosed, the model is modified in VAOne according to the actual situation.

[0048] In one embodiment, in step 5), the statistical energy model of the stiffened slab and the statistical energy model of the uniform plate are exported as a whole in XML format. Using the PreSEA plugin in the finite element modeling software PATRAN, the statistical energy models of the stiffened slab and the uniform plate are converted into an XML file recognizable by the statistical energy acoustic software and exported as superstructure.xml. After export, the statistical energy model attribute information in the statistical energy models of the stiffened slab and the uniform plate is preserved and can be recognized by the acoustic software.

[0049] In one embodiment, the acoustic software used in step 4) is VAOne. Specifically, VAOne is opened, the Frequency Domain is set according to the noise analysis frequency, the System of Units is set according to the dimensions of the finite element modeling, and the superstructure.xml file is imported. In step 5), the Create Enclosed Cavities function is used to generate a statistical energy model of the acoustic cavity.

[0050] In one embodiment, the acoustic software uses AutoSEA.

[0051] In one embodiment, the finite element modeling software used in step 1) is Hypermesh. Specifically, after the finite element model is completed, it is exported as a BDF format and named superstructure.bdf; it is then imported into the PATRAN finite element software, where the PreSEA plugin is used to convert the plate and shell elements. This operation further utilizes Hypermesh's high finite element model processing efficiency to shorten the overall modeling time.

[0052] Compared with existing technologies, this application applies the finite element model established during the ship design process to the statistical energy model for cabin noise simulation. It makes full use of the existing hull steel structure and the completed center of gravity adjustment in the finite element model. All the partitioning, sealing checks, and unit grouping of the test cabins and areas can be carried out in the finite element software. It effectively utilizes the high efficiency of the finite element software in modeling and gives full play to the advantages of statistical energy acoustic software. It can quickly generate plate and shell unit subsystems based on unit grouping and generate acoustic cavity subsystems based on the already sealed areas, which greatly improves the efficiency of cabin noise modeling.

[0053] According to a second aspect of this application, a computer storage medium for implementing the method described in any embodiment of the first aspect is also provided, which stores a computer program that, when executed by a processor, implements the ship statistical energy modeling method described in any embodiment of the first aspect.

[0054] According to a third aspect of this application, a computer storage device is also provided for implementing the method described in any embodiment of the first aspect, including a memory and a processor. The memory stores a computer program that, when executed by the processor, implements the ship statistical energy modeling method described in any embodiment of the first aspect.

[0055] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for modeling a ship's statistical energy model, characterized in that, Includes the following steps: 1) Import the full ship finite element model containing plate and shell elements into the finite element modeling software. According to the noise assessment requirements, the test compartment that needs to be detected by multiple noise detection points during noise detection will be divided into multiple compartments by custom plate and shell elements, so that only one noise detection point is set in each compartment. 2) Traverse all the compartments to be tested in the finite element model of the entire ship, and ensure that each compartment to be tested is in a closed state; 3) Screen the shell units according to the preset conditions, and classify the shell units that meet the screening conditions into a uniform plate subsystem. 4) Determine whether the selected uniform plate subsystem contains stiffened beam elements. Mark the uniform plate subsystem containing stiffened beam elements and convert it into a stiffened plate statistical energy model containing statistical energy model attribute information. Mark the uniform plate subsystem that does not contain stiffened beam elements and convert it into a uniform plate statistical energy model. 5) Export the statistical energy model of the stiffened plate and the statistical energy model of the uniform plate from the finite element simulation software to the acoustic software as a whole; 6) Generate a cavity statistical energy model for each chamber to be tested in the acoustic software, and after generating a cavity statistical energy model corresponding to each compartment in the acoustic software, delete the statistical energy model converted from the custom shell unit. 7) Establish the energy transfer relationship between the rib plate statistical energy model, the uniform plate statistical energy model, and the acoustic cavity statistical energy model to form the ship statistical energy model.

2. The ship statistical energy modeling method according to claim 1, characterized in that, In steps 3) and 4), the statistical energy model conversion plugin is used in the finite element modeling software PATRAN to perform screening and conversion operations on the plate and shell elements.

3. The ship statistical energy modeling method according to claim 1 or 2, characterized in that, In step 5), after exporting the ribbed plate statistical energy model and the uniform plate statistical energy model from the finite element simulation software and importing them into the acoustic software, a beam-column statistical energy model for simulating the support columns inside the ship's cabin is established in the acoustic software according to the ship's structure.

4. The ship statistical energy modeling method according to claim 1 or 2, characterized in that, In step 5), the connection of each statistical energy model is checked in the acoustic software to see if it meets the requirements. If it does not meet the requirements, proceed to step 2) to process the whole ship finite element model again.

5. The ship statistical energy modeling method according to claim 1 or 2, characterized in that, In step 5), the statistical energy model of the stiffened plate and the statistical energy model of the uniform plate are exported as a whole in XML format and then imported into the acoustic software.

6. A computer storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the ship statistical energy modeling method according to any one of claims 1-5.

7. A computer device, characterized in that, include: A memory and a processor, wherein the memory stores a computer program that, when executed by the processor, implements the ship statistical energy modeling method according to any one of claims 1-5.

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