CN108108569B - Rapid hull modeling method based on buoyancy surface element - Google Patents

Rapid hull modeling method based on buoyancy surface element Download PDF

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CN108108569B
CN108108569B CN201810008499.9A CN201810008499A CN108108569B CN 108108569 B CN108108569 B CN 108108569B CN 201810008499 A CN201810008499 A CN 201810008499A CN 108108569 B CN108108569 B CN 108108569B
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刘世达
刘虎
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Beihang University
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Abstract

The invention discloses a hull rapid modeling method based on a buoyancy surface element, which mainly comprises the following steps: designing main parameters of a ship body, and establishing a rough three-dimensional model of the ship body; arranging a centroid position and dividing buoyancy surface elements on the rough three-dimensional model of the ship body, performing preliminary simulation according to the buoyancy sum of the buoyancy bodies corresponding to each buoyancy surface element, and establishing a physical model of the ship body; the buoyancy surface element is used for dividing the ship body into a plurality of discrete planes, and each discrete plane is called as a buoyancy surface element; establishing a visual model of a ship body; carrying out parameter association on a physical model of a ship body and a visual model of the ship body; rendering and visual simulation are carried out, and a hull refinement model is established. The invention provides a modeling method which is based on a virtual reality technology, can realize parameter matching design and stress calculation of ship bodies with different shapes and sizes, and can adjust the design of the ship body shape at any time according to design requirements, so that designers can quickly establish a ship body model.

Description

Rapid hull modeling method based on buoyancy surface element
Technical Field
The invention relates to the technical field of virtual simulation, in particular to a hull rapid modeling method based on a buoyancy surface element.
Background
The buoyancy dynamics modeling of the ship body is an important link in the design of the ship body. Currently, in hull design iterations, the main test methods are experimental methods and Computational Fluid Dynamics (CFD) methods.
The experimental method is the most reliable method for researching the maneuverability of the ship body under the wave condition. The method performs experiments in the water tank by constructing a ship-shaped scaling model, but the experimental method is high in cost and low in efficiency due to the fact that the actual model and the water tank are manufactured, occupy the land and the like, and is particularly not suitable for frequent iteration of the primary design stage of the ship body.
The CFD method is one of the most mainstream methods applied to the current engineering, the modeling mode has a single target engineering, the complete redesign modeling is often needed after the engineering is replaced, when a plurality of models are needed, the repeated utilization rate among the models is low, and the overall design iteration process is slow; moreover, the traditional fluid calculation is an extremely complex program, the virtual fluid calculation of a large ship body usually needs a large workstation to perform operation processing for hours or even days, and due to the coupling effect of each grid in CFD grid division, the simplification of the grid can cause wrong results. In the early stage of design, the design of the ship body usually focuses more on the overall control rather than on each detail, so that the CFD method is deficient in the calculation efficiency of the macroscopic control stage in the early stage of design and cannot meet the efficiency requirement of quickly modifying a scheme in the early stage of the design stage.
The dynamic modeling is carried out on the ship body by utilizing a virtual simulation mode, so that repeated modeling caused by different sizes and shapes of the ship body in the traditional dynamic modeling can be reduced to a certain extent, and the efficiency in the design iteration process is improved.
The application of the virtual reality technology starts late, particularly for a common ship body, the real-time calculation of the swaying is not important, and the wave resistance of the ship can be estimated according to an empirical formula. However, for a special ship type, such as an aircraft carrier which needs to undertake the take-off and landing tasks of a carrier-based aircraft, it is very important to calculate the swaying of the ship body under different wave levels in real time, otherwise, great difficulty is formed on the take-off and landing of the pilot, and the aircraft carrier in China just starts in 2012, and the construction research on the aircraft carrier is still preliminary. Therefore, the requirement for realizing rapid modeling of the ship body in a virtual reality environment on an aircraft carrier is urgent.
Disclosure of Invention
Aiming at the technical problems in the related art, the invention relies on the virtual reality technology, utilizes a Physx physical engine to establish a physical model of a ship body, utilizes a Unity3D engine to establish a visual model, provides a modeling method which can realize parameter matching design and stress calculation of ship bodies with different shapes and sizes, can adjust the shape design of the ship body at any time according to the design requirements, enables designers to quickly establish the ship body model, and can be used for early iterative design of the designers, virtual training of the personnel on the ship and the like.
In order to achieve the technical purpose, the technical scheme of the invention comprises the following steps:
s1: designing main parameters of the ship body, and establishing a rough three-dimensional model of the ship body;
s2: arranging a centroid position and dividing buoyancy surface elements on the rough three-dimensional model of the ship body, performing preliminary simulation according to the buoyancy sum of the buoyancy bodies corresponding to each buoyancy surface element, and establishing a physical model of the ship body; the buoyancy surface element is used for dividing the ship body into a plurality of discrete planes, and each discrete plane is called as a buoyancy surface element;
s3: adjusting parameters according to a simulation result of the physical model of the ship body;
s4: judging whether the physical model of the ship body reaches an expected target or not, if so, jumping to S5, otherwise, jumping to S1;
s5: establishing a visual model of the ship body;
s6: performing parameter association on the physical model of the ship body and the visual model of the ship body;
s7: judging whether the physical model of the ship body is correctly associated with the visual model of the ship body, if so, jumping to S8, otherwise, jumping to S6;
s8: rendering and visual simulation are carried out, and a detailed model of the ship body is established;
s9: and judging whether the refined model of the ship body reaches the expected target, if so, saving the design scheme, and otherwise, jumping to S5.
Further, in S2, the step of arranging a centroid position and dividing buoyancy surface elements on the rough three-dimensional model of the ship body, and performing preliminary simulation according to the sum of buoyancy forces of the buoyancy bodies corresponding to each buoyancy surface element, and the step of establishing the physical model of the ship body specifically includes:
s21: determining the number n of the buoyancy surface elements, and dividing the area of the buoyancy surface elements according to the shape of the bottom of the ship body;
s22: judging the calculation requirement, judging whether the calculation speed is required to be greater than the calculation precision, if so, jumping to S23, otherwise, jumping to S24;
s23: carrying out random surface element sampling calculation on the buoyancy surface element;
s24: carrying out fixed surface element sampling calculation on the buoyancy surface element;
s25: scanning each buoyancy surface element upwards in a plumb mode to generate each buoyancy body corresponding to each buoyancy surface element, and acquiring the characteristic volume of each buoyancy body, so that the soaking proportion delta of each buoyancy body is calculated;
s26: calculating the buoyancy F of each buoyancy bodybuoyancyAnd solving the sum of the buoyancy of all the buoyancy bodies;
s27: carrying out visual simulation, and establishing a physical model of the ship body; the visualization simulation is carried out, and the physical model of the ship body is established by using a Unity3D engine and a Physx engine.
Further, in S21, the number n of buoyancy bins satisfies: 50< n < 500.
Further, in S21, the area of the buoyancy surface element should cover all the part of the hull immersed in the water surface, and is a closed area; for a symmetrical hull, the area of the buoyancy surface element comprises a symmetrical area.
Further, in S23, the random bin sampling is to randomly select a part of the buoyancy bins for sampling calculation, so as to reduce the calculation amount.
Further, in S24, the fixed bin sampling may be a sampling calculation for all the buoyancy bins in fixed steps.
Further, in S24, the fixed bin sampling may also be a sampling calculation for a preselected portion of the buoyancy bins from all of the buoyancy bins.
Further, in S25, the calculation formula of the immersion ratio δ of the buoyant body is:
Figure BDA0001539472550000031
wherein H1The height of the sea wave at the upper part of the plumb bob of the geometric center of the buoyancy surface element; h2The height of the edge of the buoyancy body at the geometric center of the buoyancy surface element and above the plumb direction is defined; h3The height of the geometric center of the buoyancy surface element.
Further, in S26, the buoyancy F of the buoyant bodybuoyancyThe calculation formula of (2) is as follows:
Figure BDA0001539472550000032
wherein, CBIs a global buoyancy adjustment constant, ideally CBHas a value of 1; rhowaterIs the density of water; g is a gravity constant; vvolumeIs the volume of the hull; ccountThe number of buoyancy bins chosen for each frame in the Unity3D engine.
Preferably, in S6, the parameter association is mainly embodied in the centroid position, the geometric center position of the buoyancy bin, the propeller thrust position and the propeller direction.
The invention has the beneficial effects that:
1) the method is based on the virtual reality technology, has short period and low cost, and does not have high requirements of an experimental method on a field and a physical model. The Physx is used for rapidly completing the engineering calculation of dynamics in the initial stage of design, and meanwhile, the Unity3D is used for visualizing the engineering calculation, so that designers can perform vivid and reliable task simulation indoors in the early stage through a computer, and the design method has profound significance for the whole design period and future training exercises.
2) The invention has low requirement on the computing capability of the computer, has single-step computing time less than 0.02 second, and meets the real-time requirement of virtual reality. The method provided by the invention can be used for quickly adjusting different parameters according to different ship sizes and shapes, quickly obtaining intuitive force calculation and evaluating and modifying the design mode at an early stage, thereby iteratively modifying the ship design and greatly improving the efficiency of design work.
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In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a flow chart of a modeling method of an embodiment of the invention;
FIG. 2 is a flow chart of establishing a physical model of a hull according to an embodiment of the present invention;
FIG. 3 is a rough three-dimensional model of a hull of an embodiment of the invention;
FIG. 4 is a schematic illustration of the division of the buoyancy panels of the hull of an embodiment of the present invention;
FIG. 5 is a schematic view of a single buoyant body of an embodiment of the present invention;
FIG. 6 is a schematic diagram illustrating a calculation of the soaking ratio of a single buoyant body according to an embodiment of the present invention;
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.
Referring to fig. 1, an embodiment of the present invention provides a hull rapid modeling method based on a buoyancy surface element, including the following steps:
s1: designing main parameters of a ship body, and establishing a rough three-dimensional model of the ship body;
the main parameters of the hull include: the overall length, the length between vertical lines, the profile width, the profile depth, the draught, the displacement, the propeller position, the control surface position and the like, and a rough three-dimensional model of the ship body is established as shown in figure 3.
S2: arranging a centroid position and dividing buoyancy surface elements on the rough three-dimensional model of the ship body, performing preliminary simulation according to the buoyancy sum of the buoyancy bodies corresponding to each buoyancy surface element, and establishing a physical model of the ship body; the buoyancy surface element is used for dividing the ship body into a plurality of discrete planes, each discrete plane is called as a buoyancy surface element, and the buoyancy condition of the ship body is calculated in real time according to the buoyancy surface elements; the sum of the buoyancy provided by all the buoyancy panels should be equal to the displacement of the ship body;
the specific steps for establishing the physical model of the hull are shown in fig. 2:
s21: determining the number n of buoyancy surface elements, and dividing the area of the buoyancy surface elements according to the shape of the bottom of the ship body;
the division of the buoyancy surface element should follow the principle of uniformity and reasonability, and specifically should satisfy:
(1) the division number of the buoyancy surface elements is reasonable;
(2) the symmetrical ship body requires symmetrical buoyancy surface elements;
(3) the buoyancy surface element should cover all hull parts that may be submerged in the water;
(4) the buoyancy surface elements are integrated into a closed body and can reflect the complete basic shape of the ship body.
The more the buoyancy surface elements are divided, the more vivid visual result is, but the requirement on the computing capacity of a computer or a workstation is higher, and 50-500 buoyancy surface elements can be divided according to the size of a ship body. The embodiment of the invention takes 350 buoyancy surface elements, and the division schematic diagram for obtaining the buoyancy surface elements of the ship body is shown in fig. 4.
S22: judging the calculation requirement, judging whether the calculation speed is required to be greater than the calculation precision, if so, jumping to S23, otherwise, jumping to S24;
according to the actual requirements of ship body modeling, if the modeling is required to be rapidly realized, under the condition of ensuring certain precision, jumping to the step S23, and carrying out random surface element sampling calculation on the buoyancy surface element; otherwise, jumping to step S24, performing fixed bin sampling calculation on the buoyancy bin.
S23: carrying out random surface element sampling calculation on the buoyancy surface element;
for complex shaped hulls, the division of the buoyancy bins can be as many as several hundred, making them involved in the calculation of each step at the same time is a burden for the use of a computer. According to the principle of virtual reality optimization, in order to reduce the amount of calculation, some random positions of each frame are selected to be calculated instead of all random positions participating in calculation, and the method is called as a random binning sampling method.
S24: carrying out fixed surface element sampling calculation on the buoyancy surface element;
the fixed surface element sampling is to perform sampling calculation on all buoyancy surface elements by using a single step length, or to perform sampling calculation on part of the buoyancy surface elements which can represent the properties of the buoyancy body and are preselected from all the buoyancy surface elements.
S25: scanning each buoyancy surface element upwards in a plumb mode to generate a buoyancy body corresponding to each buoyancy surface element, and acquiring the characteristic volume of each buoyancy body, so that the immersion proportion delta of each buoyancy body is calculated;
scanning each buoyancy surface element selected in step S24 or S25 upward in plumb to generate a buoyancy body corresponding to each buoyancy surface element, wherein a schematic diagram of a single buoyancy body is shown in fig. 5, and a characteristic volume of each buoyancy body is marked as VcellReferring to fig. 6, the soaking ratio of the individual buoyant body is further calculated, in fig. 6, V1、V2All the buoyancy bodies are buoyancy bodies, after the smooth bottom surface of the ship body is divided into a plurality of buoyancy surface elements, a reference point is taken at the geometric center of each buoyancy surface element, and the height H of the geometric center of each buoyancy surface element is read3The ray is emitted upwards from the vertical direction of the reference point, and the height of the outer contour of the hit ship body, namely the height of the edge of the upward part of the plumb of the geometric center of the buoyancy surface element of the buoyancy body, is recorded as H2The height of the sea surface, i.e. the height of the sea wave at the vertical position of the geometric center of the buoyancy surface element, is recorded as H1. Here, H1Is a local dynamic value generated by wave modeling, which varies with the local sea surface height. To meet the real-time requirements, the soaking proportion delta of a single buoyancy body is defined:
Figure BDA0001539472550000061
if the buoyancy body is completely immersed in water, H2＜H1If delta is 1; if the buoyancy body completely leaves the water surface, H3＞H1If δ is 0.
S26: calculating the buoyancy F of each buoyancy bodybuoyancyAnd obtaining the buoyancy F of the ship body;
and carrying out buoyancy calculation on the ship body according to the selected buoyancy surface element. The ship body stress is simplified as follows: buoyancy, resistance, and buoyancy and resistance are independent of each other, and here, the flow force that produces to the wave is never calculated.
1) Buoyancy force
According to the buoyancy formula:
Fbuoyancy＝ρwatergVdis(3)
where ρ iswaterIs the density of water, g is the gravitational constant, VdisIs the volume of water displaced. Therefore, the area of each buoyancy panel needs to be converted to displacement volume.
An intuitive solution is Vdis＝Scell*h，ScellIs the projection of the area of a single buoyancy surface element on the horizontal plane, h is the water entry depth # of the single buoyancy surface element area, but ScellThe normal direction of the bottom surface of each buoyancy surface element is changed every frame, which means that each buoyancy surface element needs to solve one more normal three-dimensional vector every frame.
In order to further meet the real-time requirement, the method simplifies other parts except the water entry depth into a constant, and combines the soaking proportion delta, and comprises the following steps:
Vdis＝Scellh＝Vcellδ (4)
Figure BDA0001539472550000071
in the formula (5), VvolumeIs the volume of the hull, CcountThe number of buoyancy bins is taken for each frame.
The buoyancy F of the buoyancy body corresponding to a single buoyancy surface elementbuoyancyCan be simplified as follows:
Figure BDA0001539472550000072
wherein, CBIs a global buoyancy adjustment constant, ideally CBHas a value of 1; the buoyancy F of a single buoyancy body can be obtained by solving the soaking proportion delta in the formula (2)buoyancyThe calculation steps are reduced, and the modeling speed is accelerated.
Binning all buoyancy into FbuoyancySumming to provide a buoyancy sum F of the hullbuoyancy(total)：
Fbuoyancy(total)＝CBρwatergVvolumeδtotal(6)
2) Resistance force
According to the formula of resistance:
Fdrag＝-0.5ρwaterSV2(7)
wherein S is the characteristic area of the buoyancy surface element, and V is the speed of the object motion.
Similar to the buoyancy solution, the characteristic area S of the buoyancy surface element is a variable influenced by the velocity V direction of the buoyancy surface element, and in order to simplify the calculation, the characteristic area S of each buoyancy surface element is avoided to be solved, and the characteristic area S of the buoyancy surface element is estimated by introducing the water immersion ratio δ in the same method as that in the buoyancy solution.
Figure BDA0001539472550000073
Wherein S isareaThe total surface area of the set of buoyancy bins for the hull, whose values can be directly obtained by software in 3D modeling.
The single buoyancy surface element is in the water at VlocalResistance F generated during speed movementdragCan be simplified as follows:
Figure BDA0001539472550000081
wherein, CDFor a global resistance adjustment constant, ideally it should be 1.
F of individual buoyancy panelsdragSumming to provide a sum F of the drag of the hulldrag(total)：
Fdrag(total)＝-0.5CDρwaterSareaδtotal|Vlocal|2(10)
And calculating the buoyancy F of the ship body by a Physx engine according to the sum of the buoyancy and the resistance.
S27: carrying out visual simulation, and establishing a physical model of the ship body; the visualization simulation is carried out, and the physical model of the ship body is established by using a Unity3D engine and a Physx engine.
Unity3D is one of the most widely used game engines at present, and its realistic visual effect and excellent function of internal physical attribute calculation make it popular among many developers in the field of virtual simulation. Meanwhile, personal versions of the system are free, open source codes and the like, so that the system is easy to receive, developers can use Unity3D to quickly and simply modify different physical models and display visual models of the systems more intuitively, and the flow advancing speed is greatly increased.
Physx is a well-known physical simulation software, which operates through a CPU or an independent floating-point processor to simulate a real physical effect, so that the motion of another virtual object in virtual simulation conforms to the physical law of the real world, and the reality degree of virtual simulation is increased.
Through two engines of Physx and Unity3D, visual simulation can be created in a computer, and the requirements of vivid visual effect and reliable physical movement are met.
S3: adjusting parameters according to a simulation result of a physical model of a ship body;
s4: judging whether the physical model of the ship body reaches an expected target, if so, jumping to S5, otherwise, jumping to S1;
s5: establishing a visual model of a ship body;
s6: carrying out parameter association on a physical model of a ship body and a visual model of the ship body;
the parameter association is mainly embodied in the position of a mass center, the geometric center position of a buoyancy surface element, the thrust position and the direction of a propeller.
S7: judging whether the physical model of the ship body is correctly associated with the visual model of the ship body, if so, jumping to S8, otherwise, jumping to S6;
s8: rendering and visual simulation are carried out, and a hull refinement model is established;
and (5) refining the map and the illumination, finishing the rendering of the model and enhancing the reality degree of the visual model.
S9: and judging whether the refined model of the ship body reaches the expected target, if so, saving the design scheme, and otherwise, jumping to S5.
It should be understood by those skilled in the art that the timing sequence of the method steps provided in the above embodiments may be adaptively adjusted according to actual situations, or may be concurrently performed according to actual situations.
All or part of the steps in the methods according to the above embodiments may be implemented by a program instructing related hardware, where the program may be stored in a storage medium readable by a computer device and used to execute all or part of the steps in the methods according to the above embodiments. The computer device includes: personal computer, server, network equipment, intelligent mobile terminal, intelligent home equipment, wearable intelligent equipment, vehicle-mounted intelligent equipment and the like; the storage medium includes: RAM, ROM, magnetic disk, magnetic tape, optical disk, flash memory, U disk, removable hard disk, memory card, memory stick, network server storage, network cloud storage, etc.
The "frame" is an operation unit of Unity3D engine, and means that several pictures are displayed per second, and each frame is calculated once, for example: 30 frames show 30 pictures per second.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (7)

1. A hull rapid modeling method based on a buoyancy surface element is characterized by comprising the following steps:
s1: designing main parameters of the ship body, and establishing a rough three-dimensional model of the ship body;
s2: arranging a centroid position and dividing buoyancy surface elements on the rough three-dimensional model of the ship body, performing preliminary simulation according to the buoyancy sum of the buoyancy bodies corresponding to each buoyancy surface element, and establishing a physical model of the ship body; the buoyancy surface element is used for dividing the ship body into a plurality of discrete planes, and each discrete plane is called as a buoyancy surface element;
s3: adjusting parameters according to a simulation result of the physical model of the ship body;
s4: judging whether the physical model of the ship body reaches an expected target or not, if so, jumping to S5, otherwise, jumping to S1;
s5: establishing a visual model of the ship body;
s6: performing parameter association on the physical model of the ship body and the visual model of the ship body;
s7: judging whether the physical model of the ship body is correctly associated with the visual model of the ship body, if so, jumping to S8, otherwise, jumping to S6;
s8: rendering and visual simulation are carried out, and a detailed model of the ship body is established;
s9: judging whether the hull refinement model reaches an expected target or not, if so, saving the design scheme, otherwise, jumping to S5;
in S2, the step of arranging a centroid position and dividing buoyancy surface elements on the rough three-dimensional model of the ship body, and performing preliminary simulation according to the sum of buoyancy of the buoyancy bodies corresponding to each buoyancy surface element, and the step of establishing the physical model of the ship body specifically includes:
s21: determining the number n of the buoyancy surface elements, and dividing the area of the buoyancy surface elements according to the shape of the bottom of the ship body;
s22: judging the calculation requirement, judging whether the calculation speed is required to be greater than the calculation precision, if so, jumping to S23, otherwise, jumping to S24;
s23: carrying out random surface element sampling calculation on the buoyancy surface element;
s24: carrying out fixed surface element sampling calculation on the buoyancy surface element;
s25: scanning each buoyancy surface element upwards in a plumb mode to generate each buoyancy body corresponding to each buoyancy surface element, and acquiring the characteristic volume of each buoyancy body, so that the soaking proportion delta of each buoyancy body is calculated;
s26: meterCalculating the buoyancy F of each buoyancy bodybuoyancyAnd the sum of the buoyancy of all the buoyancy bodies is obtained, namely the buoyancy F of the ship body;
s27: carrying out visual simulation, and establishing a physical model of the ship body; performing visual simulation, and establishing a physical model of the ship body by using a Unity3D engine and a Physx engine;
in S25, the formula for calculating the immersion ratio δ of the buoyant body is:
Figure FDA0002447394200000011
wherein H1The height of the sea wave at the upper part of the plumb bob of the geometric center of the buoyancy surface element; h2The height of the edge of the buoyancy body at the geometric center of the buoyancy surface element and above the plumb direction is defined; h3The height of the geometric center of the buoyancy surface element is defined as the height of the geometric center of the buoyancy surface element;
in S26, the buoyancy F of the buoyant bodybuoyancyThe calculation formula of (2) is as follows:
Figure FDA0002447394200000021
wherein, CBThe value of CB is ideally 1 for a global buoyancy adjustment constant; rhowaterIs the density of water; g is a gravity constant; vvolumeIs the volume of the hull; ccountThe number of buoyancy bins chosen for each frame in the Unity3D engine.
2. The hull rapid modeling method based on buoyancy surface elements according to claim 1, characterized in that in S21, the number n of buoyancy surface elements satisfies: 50< n < 500.
3. The method for rapidly modeling a hull based on buoyancy panels according to claim 2, wherein in S21, the area of the buoyancy panel should cover all parts of the hull immersed in the water surface and is a closed area; for a symmetrical hull, the area of the buoyancy surface element comprises a symmetrical area.
4. The hull rapid modeling method based on buoyancy surface elements according to claim 3, characterized in that in S23, the random surface element sampling is to randomly select part of the buoyancy surface elements for sampling calculation, so as to reduce the calculation amount.
5. The hull rapid modeling method based on buoyancy bins according to claim 4, characterized in that in S24, the fixed bin sampling is a sampling calculation for all the buoyancy bins by a fixed step.
6. The method according to claim 4, wherein in S24, the fixed bin sampling is a sampling calculation from a preselected portion of all the buoyancy bins.
7. The method for rapidly modeling a hull based on a buoyancy bin according to any one of claims 1 to 6, wherein in S6, the parameter association is mainly embodied in the position of a centroid, the position of a geometric center of the buoyancy bin, the position of thrust of a propeller and the direction.
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