A model-based method and system for determining a fixed floating volume of an underwater irregular object

Abstract

This invention discloses a model-based method and system for determining the fixed buoyancy volume of an irregular underwater object. The method includes: acquiring three-dimensional geometric model data of an underwater device; monitoring the immersion depth D of the underwater device in water in real time using sensors; and obtaining the total volume V of the underwater device based on the three-dimensional geometric model data and the immersion depth D. t and immersion volume V d Based on the total volume V of the underwater device t and immersion volume V d Obtain the initial fixed buoyancy volume of the underwater device; analyze the surface state of the object, and use a fluid dynamics model to calculate the hydrodynamic force F acting on the underwater device. d Based on the initial fixed buoyancy volume and hydrodynamic force F d The final fixed floating volume is obtained. This invention comprehensively considers fluid dynamics factors, simplifies the calculation process, has strong adaptability, and improves calculation accuracy.

Description

Technical Field

[0001] This invention belongs to the field of computer systems engineering, and in particular relates to a model-based method and system for determining the fixed buoyancy volume of irregular underwater objects. Background Technology

[0002] In the design and application of underwater equipment, buoyancy and stability are crucial factors. With the development of underwater technology, particularly in fields such as marine resource development, environmental monitoring, and underwater robotics, the demand for accurate calculations of buoyancy and buoyancy volume is increasing. Buoyancy volume refers to the volume occupied by an object in water, directly affecting its buoyancy and stability. Therefore, accurately calculating the buoyancy volume of underwater equipment has become an important research topic in related technologies.

[0003] Traditional buoyancy calculations typically employ Archimedes' principle, which states that the buoyant force on an object equals the weight of the water it displaces. While simple and easy to understand, this method is limited in complex underwater environments, especially when the object has an irregular shape or changing water flow conditions. Buoyancy calculations depend not only on the object's geometry but also on the velocity and pressure distribution of the surrounding water flow, as well as the properties of the object's surface. Therefore, traditional methods for calculating buoyant volume often contain errors and cannot meet high-precision requirements.

[0004] In recent years, with the development of computational fluid dynamics (CFD) technology, researchers have begun to apply fluid dynamics models to the calculation of buoyancy. CFD technology can simulate the complex behavior of water flow and obtain the fluid dynamics acting on the surface of an object through flow field analysis. This method provides a more accurate means of buoyancy calculation, but it also introduces higher computational complexity and higher demands on computing resources. Summary of the Invention

[0005] To address the shortcomings of the existing technology, this invention provides a model-based method for determining the fixed buoyancy volume of irregular underwater objects, comprising the following steps:

[0006] Step S101: Obtain the three-dimensional geometric model data of the underwater equipment;

[0007] Step S103: Monitor the immersion depth D of the underwater equipment in water in real time using sensors, and use it as an input parameter for calculating the fixed buoyancy volume;

[0008] Step S105: Based on the three-dimensional geometric model data of the underwater device and the immersion depth D, obtain the total volume V of the underwater device. t and immersion volume V d ;

[0009] Step S107: Based on the total volume V of the underwater device t and immersion volume V d Obtain the initial fixed buoyancy volume of the underwater equipment;

[0010] Step S109: Analyze the surface state of the object and use a fluid dynamics model to calculate the hydrodynamic force F acting on the underwater equipment. d ;

[0011] Step S1011, based on the initial fixed buoyancy volume and hydrodynamic force F d To obtain the final fixed floating volume.

[0012] The three-dimensional geometric model data is obtained through laser scanning or computer-aided design (CAD) software.

[0013] The three-dimensional geometric model data includes the shape, volume, and surface features of the underwater equipment.

[0014] The immersion depth D is obtained by monitoring water level changes or by geometric calculation of the three-dimensional geometric model data.

[0015] Wherein, the immersion volume V d The following formula is used for calculation:

[0016] Where H is the maximum height of the underwater equipment.

[0017] In step S107, the initial fixed floating volume is calculated using the following formula:

[0018] Where, ρ ω Where is the density of water; g is the acceleration due to gravity; H is the maximum height of the underwater device; N is the number of selected surface feature points; A i z is the area of ​​the i-th surface feature point; i Let be the height coordinates of the i-th feature point; δ be the standard deviation of the Gaussian distribution; and M be the total mass of the underwater equipment.

[0019] Step S109 includes calculating the hydrodynamic force F using the following formula. d :

[0020] Where, x i The coordinates of the i-th surface feature point on the object's surface are represented by n. i It refers to point x i The normal vector at point A; i p(x) represents the area of ​​the i-th surface feature point. i ) represents point x iThe fluid pressure at the location; μ is the dynamic viscosity of the fluid; The surface S containing the i-th surface feature point i velocity gradient on; t i This represents the tangent vector, which runs parallel to the direction of fluid flow along the surface of the object.

[0021] The flow field was calculated using fluid dynamics simulation software to obtain the pressure p(x) at each coordinate point. i ).

[0022] In step S1011, the final fixed floating volume is calculated using the following formula:

[0023]

[0024] This invention also proposes a model-based device for determining the fixed buoyancy volume of irregular underwater objects, including...

[0025] The 3D geometric model data acquisition module is used to acquire the 3D geometric model data of underwater equipment.

[0026] A sensor is used to monitor the immersion depth D of the underwater device in water in real time, as an input parameter for calculating the fixed buoyancy volume;

[0027] The volume acquisition module is used to acquire the total volume V of the underwater device based on the three-dimensional geometric model data of the underwater device and the immersion depth D. t and immersion volume V d ;

[0028] An initial fixed floating volume acquisition module is used to obtain the volume V of the underwater device. t and immersion volume V d Obtain the initial fixed buoyancy volume of the underwater equipment;

[0029] The hydrodynamic acquisition module is used to analyze the surface state of an object and calculate the hydrodynamic force F acting on the underwater equipment using a fluid dynamics model. d ;

[0030] The final fixed buoyancy volume acquisition module is used to obtain the initial fixed buoyancy volume and the hydrodynamic force F. d To obtain the final fixed floating volume.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] This invention achieves accurate calculation of buoyancy volume by comprehensively considering the surface characteristics of an object, hydrodynamic effects, and the object's mass. Compared with traditional calculation methods based on Archimedes' principle, this invention can provide a more accurate buoyancy assessment in complex water flow environments. This improved accuracy allows designers to better predict the buoyancy performance of underwater equipment, avoiding the risk of equipment instability or sinking due to inaccurate buoyancy volume calculations.

[0033] This invention introduces dynamic characteristics related to water flow depth and velocity, enabling the calculation of buoyancy volume to adapt to different underwater environments. This adaptability allows the invention to provide reliable buoyancy volume assessments under various operating conditions (such as different water flow velocities, temperatures, and densities), greatly expanding its application scope.

[0034] By combining fluid dynamics models with buoyancy volume calculations, this invention can more comprehensively reflect the impact of water flow on buoyancy. This integrated approach not only improves the scientific rigor of the calculations but also provides a more comprehensive reference for the design of underwater equipment, helping designers optimize equipment shape and surface features, thereby enhancing the equipment's performance in water.

[0035] Despite the introduction of some complex fluid dynamics factors, its structure remains relatively simple and can be calculated using conventional numerical methods such as numerical integration. This simplification allows for faster calculation of floating volumes in engineering applications, saving time and computational resources, and offering better engineering practicality compared to some complex CFD simulations.

[0036] This invention also provides a workable framework that enables the evaluation and optimization of buoyancy volume in the early design stages. This helps identify potential problems early in the object's design process, reducing the cost and time lost due to later modifications. Design schemes can be rapidly iterated by adjusting the geometry or material properties of the object's surface to achieve optimal buoyancy performance.

[0037] This invention, by improving the accuracy and adaptability of floating volume calculation, helps to advance the entire underwater technology field and promote safer and more efficient underwater operations.

[0038] By improving the accuracy and engineering practicality of floating volume calculations, this invention helps reduce the risks associated with the practical use of underwater equipment and decreases the occurrence of accidents. This not only extends the lifespan of the equipment but also reduces maintenance and operating costs, resulting in significant economic benefits. Attached Figure Description

[0039] The above and other objects, features, and advantages of exemplary embodiments of the present disclosure will become readily apparent upon reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of the present disclosure are illustrated by way of example and not limitation, and like or corresponding reference numerals denote like or corresponding parts, wherein:

[0040] Figure 1 This is a flowchart illustrating a model-based method for determining the fixed buoyancy volume of an irregular underwater object according to an embodiment of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0042] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0043] It should be understood that although the terms first, second, third, etc., may be used to describe... in the embodiments of the present invention, these... should not be limited to these terms. These terms are only used to distinguish... For example, first... may also be referred to as second... without departing from the scope of the embodiments of the present invention, and similarly, second... may also be referred to as first...

[0044] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0045] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0046] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0047] The optional embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0048] Example 1

[0049] like Figure 1 As shown, this invention discloses a model-based method for determining and evaluating the fixed buoyancy volume of irregular underwater objects, comprising the following steps:

[0050] Step S101: Obtain the three-dimensional geometric model data of the underwater equipment;

[0051] Step S103: Monitor the immersion depth D of the underwater equipment in water in real time using sensors, and use it as an input parameter for calculating the fixed buoyancy volume;

[0052] Step S105: Based on the three-dimensional geometric model data of the underwater device and the immersion depth D, obtain the total volume V of the underwater device. t and immersion volume V d ;

[0053] Step S107: Based on the total volume V of the underwater device t and immersion volume V d Obtain the initial fixed buoyancy volume of the underwater equipment;

[0054] Step S109: Analyze the surface state of the object and use a fluid dynamics model to calculate the hydrodynamic force F acting on the underwater equipment. d ;

[0055] Step S1011, based on the initial fixed buoyancy volume and hydrodynamic force F d To obtain the final fixed floating volume.

[0056] In step S101, multiple cameras are deployed to capture images of the object from different angles; image processing algorithms are used to convert the image data into a three-dimensional point cloud; and point cloud reconstruction technology is applied to generate a high-precision three-dimensional model.

[0057] Example 2

[0058] This invention proposes a model-based method for determining the fixed buoyancy volume of irregular underwater objects, comprising the following steps:

[0059] Step S101: Obtain the three-dimensional geometric model data of the underwater equipment;

[0060] Step S103: Monitor the immersion depth D of the underwater equipment in water in real time using sensors, and use it as an input parameter for calculating the fixed buoyancy volume;

[0061] Step S105: Based on the three-dimensional geometric model data of the underwater device and the immersion depth D, obtain the total volume V of the underwater device. t and immersion volume V d ;

[0062] Step S107: Based on the total volume V of the underwater device t and immersion volume V d Obtain the initial fixed buoyancy volume of the underwater equipment;

[0063] Step S109: Analyze the surface state of the object and use a fluid dynamics model to calculate the hydrodynamic force F acting on the underwater equipment. d ;

[0064] Step S1011, based on the initial fixed buoyancy volume and hydrodynamic force F d To obtain the final fixed floating volume.

[0065] The three-dimensional geometric model data is obtained through laser scanning or computer-aided design (CAD) software.

[0066] The three-dimensional geometric model data includes the shape, volume, and surface features of the underwater equipment.

[0067] The immersion depth D is obtained by monitoring water level changes or by geometric calculation of the three-dimensional geometric model data.

[0068] The step of determining the immersion depth D may further include analyzing different environmental conditions (such as water temperature and salinity) to correct for the water density ρ. w For example, by using sensors to monitor water temperature and salinity in real time, the density of water can be corrected using relevant formulas: ρ w ′=ρ w (1-β(T-T0)), where β is the temperature coefficient of water, T is the current temperature, and T0 is the standard temperature.

[0069] Wherein, the immersion volume V d The following formula is used for calculation:

[0070] Where H is the maximum height of the underwater equipment.

[0071] In step S107, the initial fixed floating volume is calculated using the following formula:

[0072] Where, ρ ω Where is the density of water; g is the acceleration due to gravity; H is the maximum height of the underwater device; N is the number of selected surface feature points; A i z is the area of ​​the i-th surface feature point; i Let be the height coordinates of the i-th feature point; δ be the standard deviation of the Gaussian distribution; and M be the total mass of the underwater equipment.

[0073] Step S109 includes calculating the hydrodynamic force F using the following formula. d :

[0074] Where, x i The coordinates of the i-th surface feature point on the object's surface are represented by n. i It refers to point x i The normal vector at point A; i p(x) represents the area of ​​the i-th surface feature point. i ) represents point x i The fluid pressure at the location; μ is the dynamic viscosity of the fluid; The surface S containing the i-th surface feature point i velocity gradient on; t i This represents the tangent vector, which runs parallel to the direction of fluid flow along the surface of the object.

[0075] In one embodiment, the geometric model of the object is obtained using computer-aided design (CAD) software or 3D scanning. The model is discretized into N grids, and the vertex coordinates of each grid are x. i This is a three-dimensional coordinate, usually represented as (x, y, z) in three-dimensional space.

[0076] For each mesh, the formula for calculating the normal vector can be used. For the three vertices v1, v2, v3 of the face, then...

[0077] Here, × represents the cross product, and the resulting n i It is the unit normal vector.

[0078] The dynamic viscosity μ of a fluid can be obtained by consulting fluid property tables or by experimental determination.

[0079] In CFD, the velocity field is pre-calculated, and the velocity gradient on each grid can be obtained numerically.

[0080] The tangent vector is usually related to the relationship between the normal vector and the flow direction. It can be obtained by the cross product of the fluid velocity vector and the normal vector: t i =v fi -(v fi ·n i )n i , where v fi It is point x i The fluid velocity vector at that location.

[0081] The flow field was calculated using fluid dynamics simulation software to obtain the pressure p(x) at each coordinate point. i ).

[0082] Fluid dynamics simulation software includes ANSYS Fluent or OpenFOAM, among others.

[0083] Among them, using computational fluid dynamics (CFD) methods to calculate hydrodynamics can numerically simulate fluid flow characteristics, specifically:

[0084] Establish a fluid domain model and define boundary conditions;

[0085] CFD software was used to simulate the flow field and calculate the pressure distribution acting on the surface of the object.

[0086] By combining pressure distribution with model characteristics, hydrodynamics can be obtained.

[0087] In step S1011, the final fixed floating volume is calculated using the following formula:

[0088]

[0089] Example 3

[0090] This invention also proposes a model-based device for determining the fixed buoyancy volume of irregular underwater objects, including...

[0091] The 3D geometric model data acquisition module is used to acquire the 3D geometric model data of underwater equipment.

[0092] A sensor is used to monitor the immersion depth D of the underwater device in water in real time, as an input parameter for calculating the fixed buoyancy volume;

[0093] The volume acquisition module is used to acquire the total volume V of the underwater device based on the three-dimensional geometric model data of the underwater device and the immersion depth D. t and immersion volume V d ;

[0094] An initial fixed floating volume acquisition module is used to obtain the volume V of the underwater device. t and immersion volume Vd Obtain the initial fixed buoyancy volume of the underwater equipment;

[0095] The hydrodynamic acquisition module is used to analyze the surface state of an object and calculate the hydrodynamic force F acting on the underwater equipment using a fluid dynamics model. d ;

[0096] The final fixed buoyancy volume acquisition module is used to obtain the initial fixed buoyancy volume and the hydrodynamic force F. d To obtain the final fixed floating volume.

[0097] The present invention also includes a software system based on a graphical user interface, which can display the model, floating volume and dynamic analysis results in real time; implement a data acquisition module to automatically read sensor data; and combine the calculation results with a database for easy subsequent query and analysis.

[0098] Optimize the design parameters of the object based on the buoyancy volume calculation results to improve its stability in water; assess the environmental impact of the underwater object and propose improvement measures.

[0099] Example 4

[0100] This disclosure provides a non-volatile computer storage medium storing computer-executable instructions that can perform the steps described in the above embodiments.

[0101] It should be noted that the computer-readable medium described in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in connection with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0102] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0103] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (AN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0104] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0105] The units described in the embodiments of this disclosure can be implemented in software or hardware. The names of the units are not, in some cases, intended to limit the specific unit.

[0106] The preferred embodiments of the present invention have been described above to make the spirit of the present invention clearer and easier to understand, and are not intended to limit the present invention. All modifications, substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope summarized by the appended claims.

Claims

1. A method for determining a fixed floating volume of a model-based underwater device, characterized in that, The method comprises the following steps: Step S101, acquiring three-dimensional geometric model data of the underwater equipment; Step S103, real-time monitoring of the immersion depth of the underwater equipment in the water by the sensor as an input parameter for calculating the fixed floating volume; Step S105, according to the three-dimensional geometric model data of the underwater equipment and the immersion depth D, the total volume of the underwater equipment is obtained and the immersion volume ; Step S107, based on the total volume of the underwater equipment and the submerged volume , obtaining an initial fixed floating volume of the underwater equipment; Step S109, analyzing the surface state of the object, calculating the water power acting on the underwater device using a fluid dynamics model ; Step S1011, obtaining the initial fixed floating volume based on the initial fixed floating volume and the water power , obtaining the final fixed floating volume; The initial fixed floating volume in step S107 is calculated by the following formula: wherein, is the density of water; g is the acceleration of gravity; H is the maximum height of the underwater equipment; N is the number of selected surface feature points; is the area of the i-th surface feature point; is the height coordinate of the i-th feature point; is the standard deviation of the Gaussian distribution; M is the total mass of the underwater equipment; The step S109 includes calculating the hydrodynamic force using the following equation : ,in, Represents the first on the surface of an object The coordinates of a surface feature point; It refers to the point The normal vector at that location; Let i be the area of ​​the i-th surface feature point; Point The fluid pressure at the location; μ is the dynamic viscosity of the fluid; Indicates the first The surface where the surface feature points are located The velocity gradient on the surface; This represents the tangent vector, which is parallel to the direction of fluid flow along the surface of the object. The final fixed floating volume in step S1011 is calculated by the following formula:

2. The method of claim 1, wherein, The three-dimensional geometric model data is acquired by laser scanning or computer aided design (CAD) software.

3. The method of claim 2, wherein, The three-dimensional geometric model data contains the shape, volume and surface characteristics of the underwater equipment.

4. The method of claim 1, wherein, The immersion depth D is obtained by monitoring the water level change or by geometric calculation of the three-dimensional geometric model data.

5. The method of claim 1, wherein, The submerged volume The calculation is made using the following formula: where H is the maximum height of the underwater equipment.

6. The method of claim 1, wherein, The flow field is calculated by fluid dynamics simulation software to obtain the pressure of each coordinate point .

7. An apparatus using the method of claim 1, comprising a three-dimensional geometric model data acquisition module for acquiring three-dimensional geometric model data of the underwater equipment; a sensor for monitoring in real time the immersion depth of the underwater device in water as input parameters for calculating the fixed floating volume; a volume acquisition module for acquiring a total volume of the underwater device from three-dimensional geometric model data of the underwater device and the immersion depth D and an immersed volume ; an initial fixed float volume acquisition module for acquiring an initial fixed float volume of the underwater device based on a total volume of the underwater device and an immersed volume ​ a hydrodynamic acquisition module for analyzing the surface state of the object, using a fluid dynamics model to calculate the hydrodynamic forces acting on the underwater device ; an ultimate fixed floating volume acquisition module configured to acquire an ultimate fixed floating volume based on the initial fixed floating volume and the water dynamics .

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