KR101647589B1 - Modeling system for vibration analysis of hull, modeling method and computer readable medium - Google Patents

Abstract

The present invention provides a modeling system, a modeling method, and a computer reading/writing medium for analyzing vibration of a hull. The modeling system for analyzing vibration of a hull, comprises: a reference data measuring part which includes a draft calculation part for calculating first draft of a ship ran on trial, and a first vibration frequency measuring part for measuring a vibration frequency of the ship ran on trial by driving the ship ran on trial; a measurement data measuring part which includes a weight distribution setting part which makes a modeling ship have the same weight distribution as the ship ran on trial, a draft setting part which sets first draft of the modeling ship to have the same value as the first draft of the ship ran on trial, and a second vibration frequency measuring part for measuring a vibration frequency of the modeling ship; and a controller which is connected to the reference data measuring part and the measurement data measuring part, and compares the vibration frequency of the ship ran on trial with the vibration frequency of the modeling ship.

Description

TECHNICAL FIELD The present invention relates to a modeling system, a modeling method, and a computer readable recording medium for vibration analysis of a hull,

The present invention relates to a modeling system, a modeling method, and a computer-readable recording medium, and more particularly, to a modeling system and a modeling method for vibration analysis of a hull, and a computer readable recording medium .

Generally, in the case of ships, the fluctuating pressure caused by the propeller is transmitted to the hull, and excessive vibration noise is generated in the hull structure and residence area. In order to reduce the vibration noise of the propeller, it seeks a way to reduce the fluctuating pressure through the linear change or the change of the propeller, but it is limited because of the speed and the propulsion efficiency.

Therefore, studies on the modeling of the natural vibration of a ship have been actively studied. Especially, in the case of natural vibration analysis of large commercial ships, application of heavy materials such as shipment, fuel oil, and ballast water has a great influence on the analysis result, and it is important to analyze natural vibration in consideration of this.

In general, the method of heavy material modeling is mainly used to limit the concentrated mass element applied in the finite element analysis program to the part of the hull to which the weight is applied.

Embodiments of the present invention provide a modeling system, a modeling method, and a computer readable recording medium for vibration analysis of a hull having improved sensitivity.

According to an aspect of the present invention, there is provided a reference data measurement apparatus comprising a reference data measurement unit including a draft calculation unit for calculating a first draft of a test operation ship, and a first vibration frequency measurement unit for driving the test operation ship to measure a vibration frequency of the trial operation ship A weight distribution setting section for setting the weight of the modeling vessel to have the same weight distribution as that of the test operation ship, a draft setting section for setting the value of the first draft of the modeling ship equal to the value of the first draft of the test operation ship, A measurement data measurement unit having a second vibration frequency measurement unit for measuring a vibration frequency of the modeling vessel, and a second data acquisition unit connected to the reference data measurement unit and the measurement data measurement unit, wherein the vibration frequency of the test- A modeling system for vibration analysis of a hull including a controller for comparison is provided.

The first draft may be a mean draft or a trim draft.

In addition, the measurement data measuring unit may include a Concentrated mass element connection (CONM2) model, a Non-structural mass (NSM) model, a Rigdi body element model, and an Interpolation constraint element model May be used.

According to another aspect of the present invention, there is provided a method for measuring a vibration of a modeling ship, comprising the steps of: measuring a first draft of a trial ship and driving the trial ship to measure reference data relating to the vibration frequency; Measuring the measurement data relating to the vibration frequency of the modeling vessel using the weight modeling and the connection element modeling; Comparing the measured data with the measured data to determine whether the error range falls within a predetermined range and setting at least one of the heavy material modeling and the coupling factor modeling within the predetermined range, And provides a modeling method for analysis.

The first draft may be a mean draft or a trim draft.

In addition, the heavy material modeling uses a CONCENTRATED MASS ELEMENT CONNECTION (CONM2) model or a Non-structural mass (NSM) model, and the connection element modeling uses a rigid body element model or interpolation Interpolation constraint element model can be used.

A computer readable recording medium on which a program for executing a modeling method for vibration analysis of a hull according to the present invention is recorded is provided.

One embodiment of the present invention is to compare the vibration frequency of the test ship and the modeling vessel to combine the modeling factors and the sensitivity with high sensitivity and to set the weight distribution of the modeling vessel to be the same as that of the test ship. Can be improved.

1 is a block diagram illustrating a modeling system for vibration analysis of a hull according to an embodiment of the present invention.
2 is a flowchart illustrating a modeling method for vibration analysis of a hull according to another embodiment of the present invention.

Embodiments are capable of various transformations, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the embodiments, and how to accomplish them, will be apparent with reference to the following detailed description together with the drawings. However, the embodiments are not limited to the embodiments described below, but may be implemented in various forms.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like or corresponding elements throughout the drawings, and a duplicate description thereof will be omitted.

In the following embodiments, the terms first, second, and the like are used for the purpose of distinguishing one element from another element, not the limitative meaning.

In the following examples, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

In the following embodiments, terms such as inclusive or having mean that a feature or element described in the specification is present, and do not exclude the possibility that one or more other features or elements are added in advance.

In the drawings, components may be exaggerated or reduced in size for convenience of explanation. For example, the sizes and thicknesses of the respective components shown in the drawings are arbitrarily shown for convenience of explanation, and the following embodiments are not necessarily drawn to scale.

1 is a block diagram showing a modeling system 1 for vibration analysis of a hull according to an embodiment of the present invention.

The modeling system 1 for vibration analysis of the hull may include a reference data measurement unit 10, a measurement data measurement unit 20 and a controller 30. [ The modeling system (1) for the vibration analysis of the hull can choose highly sensitive modeling for the natural vibration analysis of the salmon carriers, container carriers and super crude oil carriers.

The reference data measurement unit 10 can measure the reference data having the information about the trial operation ship. The reference data measuring unit 10 can calculate data related to the vibration frequency occurring at the trial operation of the trial operation ship. The reference data measuring unit 10 may include a draft calculating unit 11 and a first vibration frequency measuring unit 12. [

The draft calculation section 11 calculates the value of the first draft of the test operation ship. The first draft may be the Mean draft or the Trim draft. The modeling system (1) for the vibration analysis of the hull can analyze the vibration of the hull using additional water mass modeling. In the case of additional water mass modeling, the average draft and the trim draft are highly sensitive, and the mean draft and the trim draft are used.

The first vibration frequency measuring unit 12 can measure the vibration frequency of the hull when the trial operation ship is running.

The measurement data measurement section 20 can measure the measurement data having information about the modeling ship. The measurement data measuring unit 20 can calculate data related to the vibration frequency of the modeling ship by using the heavy material modeling and the connecting element modeling. The measurement data measurement unit 20 may include a weight distribution setting unit 21, a draft setting unit 22, and a second vibration frequency measurement unit 23. [

The weight distribution setting section 21 can set the weight distribution of the modeling ship to be equal to the weight distribution of the trial operation ship. The weight distribution of the modeling ship can be set to be equal to the weight distribution of the trial ship in order to improve the reliability of the measurement data and minimize the error of the measurement data.

The first draft setting section 22 can be set so that the draft of the modeling ship is equal to the value of the first draft of the test operation ship. The test run ship is to be set with the mean draft and the trim draft as fixed factors, and each draft can be set equal to the first draft of the modeling vessel. In a structure such as a ship moving in a fluid near an infinite region such as seawater, an additional water mass is generated by the pressure of the fluid at the portion where the fluid structure touches. The first draft setting section 22 can select the average draft and the trim draft with the added water mass.

The second vibration frequency measuring unit 23 can measure the vibration frequency of the modeling ship using the heavy material modeling and the coupling element modeling. Natural vibration analysis can be performed through MD.NASTRAN, a general structural analysis program. Concentrated mass element connection (CONM2) models and non-structural mass (NSM) models can be used for heavy-weight modeling. Rigid body element model and Interpolation constraint element model can be used for joint element modeling.

The controller 30 may be connected to the reference data measurement unit 10 and the measurement data measurement unit 20. The controller 30 can compare the vibration frequency of the trial ship with the vibration frequency of the modeling ship.

The controller 30 can compare the reference data with the measurement data to determine whether the error range falls within a preset range. If the range of error is within the preset range, you can select the applied fixed factor and modeling. Concentrated mass element connection (CONM2) model, Non-structural mass (NSM) model, Rigdi body element, and the like are selected as fixed factors, for example, At least one of the model and the interpolation constraint element model can be selected as modeling.

2 is a flowchart illustrating a modeling method for vibration analysis of a hull according to another embodiment of the present invention.

(S10) The draft calculator (11) measures the average draft and the trim draft of the trial operation ship, and measures the first draft of the test ship 1 vibration frequency measuring unit 12 can measure the vibration frequency that occurs when the trial operation ship is driven. The reference data can be compared with the measurement data measured by the modeling ship in the controller 30 to calculate an error.

The weight distribution of the modeling vessel can be set so as to have the same weight distribution as that of the trial vessel. (S20) The reliability of the measurement data can be improved by setting the weight distribution of the modeling vessel on the basis of the trial operation condition.

(S30) Concentrated mass element connection (CONM2) model, non-structural mass (non-structural mass) model can be used to measure the measurement data on the vibration frequency of the modeling ship using heavy material modeling and connection element modeling. structural mass, NSM) model can be used. Rigid body element model and Interpolation constraint element model can be used for joint element modeling. The second vibration frequency measuring unit 23 can measure the vibration frequency of the modeling vessel. In detail, the average draft can be fixed at the first draft and the vibration frequency can be measured for each of the heavy-weight modeling and the coupling-element modeling. It is also possible to fix the trim draft at the first draft and measure the vibration frequency for each of the heavy-weight modeling and the coupling-element modeling.

(S40) The controller 30 can calculate the error rate by comparing the oscillation frequency of the reference data with the oscillation frequency of the measurement data (S40). If the error rate is within the predetermined range, the controller 30 compares the reference data with the measurement data . It is also possible to determine whether the calculated error range falls within a predetermined range.

(S50) If each error of the weighting model and the connection element modeling with respect to the average and trim drafts falls within the predetermined range, the modeling can be performed. You can choose. Concentrated mass element connection (CONM2) model, Non-structural mass (NSM) model, Rigid body element (CONM2) model with the least draft or one of the mean and trim drafts within the pre- Rigdi body element model and Interpolation constraint element model can be selected.

Meanwhile, a modeling method for vibration analysis of a hull according to an embodiment of the present invention shown in FIG. 2 can be realized by a program that can be executed by a computer and is operated by using a computer- And can be implemented in a general-purpose digital computer. The computer-readable recording medium includes a storage medium such as a magnetic storage medium (e.g., ROM, floppy disk, hard disk, etc.), optical reading medium (e.g., CD ROM,

 The modeling system 1 for vibration analysis of the hull according to an embodiment of the present invention or the modeling method for vibration analysis of the hull can be used to select the modeling for the optimized vibration analysis as described below.

82K Bulk carrier was selected as the ship, and the error rate can be calculated as shown in Table 1 below.

Fixed factor modelling Error rate (%) Species first Class 2 Class 3 Spec Fourth Mean draft CONM2 4.270 1.553 3.465 1.507 NSM 4.162 1.429 3.772 1.507 RBE2 108.243 93.913 94.737 119.829 RBE3 3.23 1.242 2.675 10.411 Trim draft CONM2 5.649 2.547 3.684 1.267 NSM 5.581 2.360 3.991 1.267 RBE2 117.027 93.478 93.684 119.795 RBE3 4.649 0.311 2.368 10.034

If the predetermined range of error in the controller 30 is less than 5%, the controller 30 may select the average draft as a fixed factor and CONM2 and NSM as modeling for optimized hull vibration analysis.

When the controller 30 is set to select the modeling with the lowest error range, the average draft can be selected as a fixed factor in the longitudinal primary mode and REB3 can be selected as the modeling. In the longitudinal secondary mode and the longitudinal tertiary mode The trim draft can be selected as a fixed factor and RBE3 can be selected by modeling. In the fourth-order mode, the trim draft can be selected as a fixed factor and CONM2 or NSM can be selected as modeling.

The modeling system (1), the modeling method, and the recording medium for vibration analysis of the hull according to an embodiment of the present invention can combine the vibration modeling factors and the levels with high sensitivity by comparing the vibration frequencies of the test ship and the modeling ship.

The modeling system (1), the modeling method and the recording medium for the vibration analysis of the hull according to the embodiment of the present invention can improve the reliability of the bar modeling selection for setting the weight distribution of the modeling ship to be the same as that of the actual start- .

The present invention has been described above with reference to preferred embodiments. It will be understood by those skilled in the art that the present invention may be embodied in various other forms without departing from the spirit or essential characteristics thereof. Therefore, the above-described embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is indicated by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

1: Modeling system for vibration analysis of hull
10: Reference data measuring section
11: draft calculator
12: First vibration frequency measuring unit
20: Measuring data measuring section
21: Weight distribution setting section
22: draft setting section
23: second vibration frequency measuring unit
30: Controller

Claims (7)

A reference data measuring unit including a draft calculation unit for calculating a first draft of a test operation ship and a first vibration frequency measurement unit for driving the test operation ship and measuring a vibration frequency of the test operation ship;
A weight distribution setting section for making the modeling vessel have the same weight distribution as that of the test operation ship; a draft setting section for setting the value of the first draft of the modeling ship equal to the value of the first draft of the test operation ship; A measurement data measurement unit having a second vibration frequency measurement unit for measuring a vibration frequency of the ship; And
And a controller connected to the reference data measuring unit and the measurement data measuring unit for comparing a vibration frequency of the test operation ship with a vibration frequency of the modeling ship. The method according to claim 1,
Wherein the first draft is a mean draft or a trim draft. The method according to claim 1,
Wherein the measurement data measuring unit comprises:
At least one of the following models is used: Concentrated mass element connection (CONM2) model, Non-structural mass (NSM) model, Rigdi body element model and Interpolation constraint element model doing. A Modeling System for Vibration Analysis of Hull. Measuring a first draft of the test ship and driving the test ship to measure reference data relating to the vibration frequency;
Setting a weight distribution of the modeling vessel to have the same weight distribution as that of the trial ship;
Setting the modeling vessel to have the first draft;
Measuring measurement data on the vibration frequency of the modeling ship using heavy material modeling and connecting element modeling;
Comparing the reference data with the measurement data to determine whether the error range falls within a preset range; And
And setting at least one modeling among the heavy material modeling and the connection element modeling within the predetermined range. 5. The method of claim 4,
Wherein the first draft is a mean draft or a trim draft. 6. The method of claim 5,
The heavy material modeling uses a CONCENTRATED MASS ELEMENT CONNECTION (CONM2) model or a non-structural mass (NSM) model,
The joint element modeling uses a rigid body element model or an interpolation constraint element model. Modeling Method for Vibration Analysis of Hull. A computer-readable recording medium storing a program for causing a computer to execute the method according to any one of claims 4 to 6.

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