阅读说明：本技术 一种基于idf数据模型的船舶不沉性标板图计算方法 (Ship unsinkability target graph calculation method based on IDF data model ) 是由 余为波 邹存伟 黄卫刚 陈伟 田斌斌 于 2019-11-25 设计创作，主要内容包括：一种基于IDF数据模型的船舶不沉性标板图计算方法,包括如下步骤：建立主船体曲面的IDF数据模型,将主船体型线的首尾轮廓线和横剖线以点集的格式建模,并进行三维表达,用idf格式保存；对舰船附体及舱室进行定义；在导入主船体船型模型基础上,进行全船完整的舱室划分,多种舱室定义,以及舱室合成、分解等操作；在建立舱室的同时定义破损舱室的渗透系数；并定义计算所需装载工况,即定义所需计算的排水量及重量重心数据；采用增加重量法计算第一类舱室灌满水后的状态；采用损失浮力法计算第三类舱室的破损后的状态；减小了所花费工时,考虑了舰的自由纵倾和横倾状态,得到浮态、舱容、稳性的变化结果；计算结果可更接近于舱室进水后船的实际状态。(A ship unsinkability standard plate graph calculation method based on an IDF data model comprises the following steps: establishing an IDF data model of the curved surface of the main hull, modeling the head and tail contour lines and the transverse section lines of the main hull molded line in a point set format, performing three-dimensional expression, and storing the three-dimensional expression in an IDF format; defining the ship appendage and the cabin; on the basis of importing the ship model of the main ship body, carrying out operations such as complete cabin division of the whole ship, definition of various cabins, cabin synthesis, cabin decomposition and the like; defining the permeability coefficient of the damaged cabin while the cabin is being established; defining and calculating the required loading working condition, namely defining the water displacement and weight gravity center data required to be calculated; calculating the state of the first class cabin after being filled with water by adopting a weight increasing method; calculating the state of the third cabin after damage by adopting a loss buoyancy method; the working hours spent are reduced, the free trim and list states of the ship are considered, and the change results of the floating state, the cabin capacity and the stability are obtained; the calculation result can be closer to the actual state of the ship after the cabin is filled with water.)

1. A ship unsinkability standard plate graph calculation method based on an IDF data model is characterized by comprising the following steps: the method comprises the following steps:

establishing an IDF data model of a ship body, establishing an IDF data model of a curved surface of a main ship body according to a ship line graph (or a rib line graph, a shape value table book and the like), modeling a head and tail contour line and a transverse section line of a main ship body line in a point set format, carrying out three-dimensional expression, and storing the three-dimensional expression in an IDF format;

secondly, defining the ship appendage and the cabin; on the basis of importing the main hull ship model, carrying out complete cabin division of the whole ship, defining various cabins (including an appendage, a liquid cabin, a watertight cabin and a watertight cabin section), synthesizing and decomposing the cabins and the like;

step three, defining the permeability coefficient of the damaged cabin while establishing the cabin; defining and calculating the required loading working condition, namely defining the water displacement and weight gravity center data required to be calculated;

calculating the state of the first cabin (the cabin is filled with seawater) after being damaged by adopting a weight increasing method; and calculating the state of the third cabin (the water inlet cabin is not filled, and the water in the cabin is communicated with the seawater outside the ship) after damage by adopting a loss buoyancy method.

2. The IDF data model-based ship unsinkability reticle map calculation method according to claim 1, wherein: in the first step, if the main hull is generated by adopting other three-dimensional commercial software, data reading or conversion can be carried out on the hull three-dimensional model to obtain point set data in a specified format.

3. The IDF data model-based ship unsinkability reticle map calculation method according to claim 1, wherein:

the specific calculation method in the fourth step is as follows: and setting the weight gravity centers of the damaged ship as W, LCG, TCG and VCG, and calculating the floating state of the damaged ship by adopting the following method:

wherein, W, LCG, TCG and VCG are weight, longitudinal, transverse and vertical coordinates of the gravity center, x, y and z are three coordinate axis directions, m is static moment of each direction, and r is the density of water; v is the volume of water to be drained;

the balance of the ship at the floating center position after being damaged meets the following equation, namely the draft d and the ship longitudinal inclination angle

repeating the formulas (2) and (3) until f₁、f₂、f₃The conditions are satisfied:

(2) and (3) in the formula, M is:

wherein:

s is the area of the water plane, X_f,Y_f,Z_fAs floating center coordinates of the water plane

I_x,I_y,I_xyMoment of inertia of water plane

L_BPIs the length of the ship and B is the width of the ship

The initial steady height of the damaged ship is

Selecting a designated cabin, selecting the designated full water filling and non-full water filling working conditions for calculation, and obtaining the water inlet volume V (m) when each cabin enters water³) The change of the trim value △ t (m) and the change of the roll angle caused by the change

Technical Field

The intellectual achievement belongs to the field of overall performance of ships and warships, and particularly relates to an optimization calculation method for compartment element calculation of an immiscibility standard plate diagram.

Background

The 'non-sinking standard plate picture' is a reference picture for the use department to adjust the sinking resistance of the ship after the ship is damaged and water is entered, is an important basis for adjusting the sinking resistance of the ship and is an important component part for guaranteeing the vitality of the ship. The main data result is the water inlet volume V (m) of each cabin when the ship is damaged and water enters each cabin³) The main technical principle is the non-sinking calculation theory, and the non-sinking performance is still widely considered to be a part of the ship hydrostatic theory, and the traditional calculation method of the non-sinking standard plate graph is based on the hydrostatic theory, namely, the research on a new balance position after the ship is damaged and immersed and the stability calculation at the new balance position.

The traditional calculation method mainly adopts manual direct calculation as a main part, and the calculation is carried out step by step according to the assumption of a classical theory and by using tools such as excel and the like. Because data such as floating state and high initial stability change after water enters all first class cabins and third class cabins below the main ship body of the whole ship are required to be calculated, each cabin corresponds to one to two calculation states (namely full water and partial water enters), the number of the states required to be calculated is hundreds, the amount of data information involved in the calculation process is large, and data in the intermediate process are various. The traditional method needs to consume more working time (generally 1-2 months), and the accuracy of the calculation result also depends on the accuracy of the assumed conditions and a large amount of process data.

In order to improve the working efficiency and relative accuracy, a reasonable and easy-to-operate calculation method needs to be adopted for engineering calculation.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a novel method and means for calculating the unsinkable target map aiming at the defects in the prior art, the method can overcome the problems of more manual definition data, large process data amount, more calculation assumption conditions, no consideration of free trim of a ship and the like in the traditional manual method, a set of complete and feasible calculation method and process of the unsinkable target map are formed, the actual theoretical state of water inflow of the ship can be simulated, and the water inflow volume V (m) required by the calculation when each cabin enters water during damage is obtained with higher efficiency³) The values of trim △ t (m) and roll induced by it

And the data result of the high initial transverse stability change value △ h (cm) provides support for the anti-sinking adjustment of the ship.

The technical scheme adopted by the method is as follows: a ship unsinkability standard plate graph calculation method based on an IDF data model comprises the following steps:

establishing an IDF (Intermediate Data Format) Data model of a main hull curved surface according to a ship line graph (or a rib line graph, a shape value table book and the like), modeling a head and tail contour line and a transverse section line of a main hull line in a point set Format, carrying out three-dimensional expression, and storing in a dot-IDF Format;

secondly, defining the ship appendage and the cabin; on the basis of importing the main hull ship model, carrying out complete cabin division of the whole ship, defining various cabins (including an appendage, a liquid cabin, a watertight cabin and a watertight cabin section), synthesizing and decomposing the cabins and the like;

step three, defining the permeability coefficient of the damaged cabin while establishing the cabin; defining and calculating the required loading working condition, namely defining the water displacement and weight gravity center data required to be calculated;

calculating the state of the first cabin (the cabin is filled with seawater) after being damaged by adopting a weight increasing method; and calculating the state of the third cabin (the water inlet cabin is not filled, and the water in the cabin is communicated with the seawater outside the ship) after damage by adopting a loss buoyancy method.

Further, in the first step, if the main hull is generated by adopting other three-dimensional commercial software, data reading or conversion can be carried out on the hull three-dimensional model to obtain point set data in a specified format;

further: the specific calculation method in the fourth step is as follows: and setting the weight gravity centers of the damaged ship as W, LCG, TCG and VCG, and calculating the floating state of the damaged ship by adopting the following method:

wherein, W, LCG, TCG and VCG are weight, longitudinal, transverse and vertical coordinates of the gravity center, x, y and z are three coordinate axis directions, m is static moment of each direction, and r is the density of water; v is the volume of water to be drained;

the balance of the ship at the floating center position after being damaged meets the following equation, namely the draft d and the ship longitudinal inclination angle

The ship transverse inclination angle theta is solved by adopting the following iterative method

Repeating the formulas (2) and (3) until f₁、f₂、f₃The conditions are satisfied:

(2) and (3) in the formula, M is:

wherein: s is the area of the water plane, X_f,Y_f,Z_fAs floating center coordinates of the water plane

I_x,I_y,I_xyMoment of inertia of water plane

L_BPIs the length of the ship and B is the width of the ship

The initial steady height of the damaged ship is

Selecting a designated cabin, selecting the designated full water filling and non-full water filling working conditions for calculation, and obtaining the water inlet volume V (m) when each cabin enters water³) The change of the trim value △ t (m) and the change of the roll angle caused by the change

And the results of the compartment elements with high initial transverse stability change value △ h (cm) are combined into an unsinkable standard plate graph.

The invention has the advantages and characteristics that:

(1) the method can quickly check the result of the compartment elements when each designated compartment of the ship enters water, namely the data results of the change of the water inlet volume, the balance floating state, the change of stability and the like, not only effectively improves the accuracy and the working efficiency of important documentation such as 'immiscibility standard plate diagram' and the like, but also can be used for the adjustment and analysis of the ship sinking resistance, the consumed working hours are reduced to about 1/3 of the past working time, the proofreading work of the files only needs to be carried out aiming at the three-dimensional work of the first three steps, and the consumed working hours are reduced to about 1/3 of the past working time.

(2) When the simulation tool is used for carrying out damage stability check calculation, the free trim and list states of the ship are considered, and the change results of the floating state, the cabin capacity and the stability are obtained. Therefore, compared with the result of the traditional calculation method, the calculation result obtained by adopting the intelligent achievement can be closer to the actual state of the ship after the cabin enters water.

Drawings

FIG. 1 is a diagram of a host hull model and modeling interface in accordance with a preferred embodiment of the present invention;

FIG. 2 is a diagram illustrating an exemplary cabin partitioning model according to a preferred embodiment of the present invention;

FIG. 3 is a flow chart of the calculation of the balance of elements tables according to the preferred embodiment of the present invention;

FIG. 4 is an exemplary graph of post-break stability calculation according to a preferred embodiment of the present invention; s

Detailed Description

The invention is further illustrated with reference to the accompanying drawings:

referring to fig. 1 and fig. 2, a ship unsinkability target graph calculation method based on an IDF data model includes the following steps:

establishing an IDF (Intermediate Data Format) Data model of a main hull curved surface according to a ship line graph (or a rib line graph, a profile value table book and the like), modeling a head and tail contour line and a transverse cutting line of a main hull line in a point set Format, performing three-dimensional expression, and storing the three-dimensional expression in an IDF Format;

secondly, defining the ship appendage and the cabin; on the basis of importing the main hull ship model, carrying out complete cabin division of the whole ship, defining various cabins (including an appendage, a liquid cabin, a watertight cabin and a watertight cabin section), synthesizing and decomposing the cabins and the like;

step three, defining the permeability coefficient of the damaged cabin while establishing the cabin; defining the loading working condition required by calculation, namely defining the displacement and weight gravity center data required by calculation;

calculating the state of the first cabin (the cabin is filled with seawater) after being damaged by adopting a weight increasing method; and calculating the state of the third cabin (the water inlet cabin is not filled, and the water in the cabin is communicated with the seawater outside the ship) after damage by adopting a loss buoyancy method.

In the first step, if the main ship body is generated by adopting other three-dimensional commercial software, data reading or conversion can be carried out on the ship body three-dimensional model to obtain point set data in a specified format;

the method for calculating the ship unsinkability standard plate graph of the IDF data model is characterized by comprising the following steps of:

the specific calculation method in the fourth step is as follows: and setting the weight gravity centers of the damaged ship as W, LCG, TCG and VCG, and calculating the floating state of the damaged ship by adopting the following method:

wherein, W, LCG, TCG and VCG are weight, longitudinal, transverse and vertical coordinates of the gravity center, x, y and z are three coordinate axis directions, m is static moment of each direction, and r is the density of water; v is the volume of water to be drained;

the balance of the ship at the floating center position after being damaged meets the following equation, namely the draft d and the ship longitudinal inclination angle

The ship transverse inclination angle theta is solved by adopting the following iterative method

Repeating the formulas (2) and (3) until f₁、f₂、f₃The conditions are satisfied:

(2) and (3) in the formula, M is:

wherein:

s is the area of the water plane, X_f,Y_f,Z_fAs floating center coordinates of the water plane

I_x,I_y,I_xyMoment of inertia of water plane

L_BPIs the length of the ship and B is the width of the ship

The initial steady height of the damaged ship is

Selecting a designated cabin, selecting the designated full water filling and non-full water filling working conditions for calculation, and obtaining the water inlet volume V (m) when each cabin enters water³) The change of the trim value △ t (m) and the change of the roll angle caused by the change

And the results of the compartment elements with high initial transverse stability change value △ h (cm) are combined into an unsinkable standard plate graph.

The invention carries out the compartment element calculation of the non-sinking standard plate diagram based on the IDF (intermediate Data Format) hull Data model, the Data format file is a simple file which can define the Data structure and can be used for describing the structure of the hull compartment curved surface structure, the universality is strong, the format is simple, the operation is easy, and the following specific calculation examples are used for explanation:

(1) establishing three-dimensional model of ship body curved surface

The modeling work of the hull curved surface is carried out in hull modeling software (open commercial software can be used and self-developed software can also be used). The curved surface of the main hull is generally a closed geometric body comprising curved surfaces of a bulbous bow and a stern closing plate, and for a complex cabin with a curved cabin wall (comprising an inner bottom curved surface), a curved cabin wall model of the complex cabin wall is also required to be created; the model of the ship body of a certain type of ship host and the modeling interface are shown in figure 1.

(2) Cabin division, definition and attribute and carrier condition definition

The definition and division process of a certain cabin is shown in figure 2. The method comprises the following specific steps:

(a) and setting environmental parameters such as a reference system, density and the like for the idf format main hull three-dimensional model.

(b) The cabins of the whole ship are defined in different modes, including the definitions of an appendage, a liquid cabin, a watertight cabin and a watertight cabin section. And establishing a three-dimensional model of the cabin by adopting operations of cabin synthesis, decomposition and the like according to different shapes of the cabin. Since the state of each compartment after flooding needs to be calculated, the compartment is also generally defined as a tank.

(c) The permeability coefficient and the effective cabin volume coefficient of the cabin are defined.

(d) The loading condition is defined as the center of gravity of the weight for the desired displacement condition.

(3) Calculating a first class of cabin

When the water inlet of the first cabin is calculated, the weight increasing method in the non-sinking theory is adopted for calculation, the selected cabin is set as a liquid cabin, the balance state of the ship after the cabin is filled with water is obtained, and the element table (namely the water inlet volume V (m) of the cabin after the selected cabin is damaged can be obtained by comparing the balance state with the balance state before the cabin is filled with water³) Induced trim value △ t (m), roll angle

And the variation value △ h (cm)) with high initial transverse stability, the specific calculation flow is shown in fig. 3, and the calculation of the floating state and the initial high stability of a certain first class cabin before damage and after being filled with water is shown in table 1.

TABLE 1

The values of the increase in the initial displacement after the water is introduced into a chamber are shown in Table 2

(4) Calculating a class III cabin

And calculating the damaged inlet water of the third cabin by adopting a loss buoyancy method, wherein the loss buoyancy method considers that the water discharge and the gravity center position of the ship are kept unchanged after the cabin enters the water. The new equilibrium state is calculated according to the weight gain method and the loss buoyancy method. Selecting a damaged cabin, calculating the stability of the specified cabin in a new balance state and a new balance position (namely calculating the inclination difference t, the roll angle and the initial stability height h), and selecting the result calculated by a loss buoyancy method.

The present example only lists the state comparison calculation method before and after the damage of a certain cabin, and the interactive interface adopting the intellectual achievement can directly select any defined cabin and combination for calculation, and the same steps are also adopted. The specific cabin breaking stability calculation module interface is shown in fig. 4.

The invention is based on establishing the digital model of the hull and the subdivision, firstly, the accurate modeling of the main hull, the appendage, the inner bottom and other curved surfaces is carried out, then, the accurate definition and division of each compartment are carried out, and the method is utilized to carry out the stability simulation calculation under the complete and damaged conditions according to the setting of the intellectual achievement, so that the compartment element when each appointed compartment is filled with water can be quickly obtained, and the change results of the floating state, the compartment capacity and the stability corresponding to the water inlet state are obtained. A relatively complete and feasible calculation method for the non-sinking target graph is formed, the actual water intake theoretical state of the ship can be simulated, and the calculation can be completed with relatively high efficiency.

The foregoing shows and describes the general principles and features of the present invention, together with the advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only for the purpose of illustrating the structural relationship and principles of the present invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.