WO2016179840A1 - Method and apparatus for simulating dam-break, and a computer readable storage medium - Google Patents

Method and apparatus for simulating dam-break, and a computer readable storage medium Download PDF

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WO2016179840A1
WO2016179840A1 PCT/CN2015/078988 CN2015078988W WO2016179840A1 WO 2016179840 A1 WO2016179840 A1 WO 2016179840A1 CN 2015078988 W CN2015078988 W CN 2015078988W WO 2016179840 A1 WO2016179840 A1 WO 2016179840A1
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water
particle
boundary
particles
time
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PCT/CN2015/078988
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French (fr)
Chinese (zh)
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唐新明
汪汇兵
欧阳斯达
叶芳宏
克利⋅保罗
普拉卡什⋅马哈斯
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国家测绘地理信息局卫星测绘应用中心
澳大利亚联邦科学与工业研究组织
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Priority to PCT/CN2015/078988 priority Critical patent/WO2016179840A1/en
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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]

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  • This paper covers the field of geoscience simulation and geographic information technology.
  • the existing method for simulating the dam break generally includes dividing the block to be simulated into a plurality of grids, each grid containing influence factors of the dam break, such as slope and sink flow.
  • the flood enters the grid, according to the influence factor of the dam break in the grid, the flow in the grid is updated according to the preset rules, and the direction of the flood is determined; after the simulation is finished, according to the sink in the grid The flow analyzes the simulation results.
  • the embodiment of the invention provides a method and device for simulating a dam break and a computer readable storage medium, which can improve the simulation precision.
  • an embodiment of the present invention provides a method for simulating a dam break, including:
  • the method further includes: saving a trend of the position of each of the calculated water particles over time.
  • the method further includes: performing a dam break analysis according to the calculated trend of the position of each of the water particles over time.
  • the method further includes: performing a three-dimensional dynamic visual display according to the calculated trend of the position of each of the water particles over time.
  • the hydrodynamic method is used to calculate a change trend of the position of each water particle according to an initial position of each of the water particles and the boundary particles, including:
  • i denotes the water particles
  • j represents the boundary particle
  • p i is the pressure of the water particles i
  • w j is the boundary of the particle j
  • f bij is the volumetric force generated by the boundary particle j on the water particle i
  • ⁇ is the density of water
  • v i is the velocity of the water particle i
  • t time
  • the speed-to-time differential for the water particle i produced by f bij The acceleration of the water particle i
  • S i is the position of the water particle i
  • S 0i is the initial position of the water particle i
  • v 0i is the initial velocity of the water particle i.
  • c is the speed of light
  • r ij is the distance between the boundary particle j and the water particle i
  • l is the radius of influence of the boundary particle
  • x ij is the boundary particle j and the water particle i The difference between the positions.
  • Embodiments of the present invention also provide a computer readable storage medium storing a computer executable An instruction to execute any of the above methods of simulating a dam breach.
  • the embodiment of the invention also provides a device for simulating a dam break, comprising:
  • a dividing module configured to divide water in the area to be simulated into two or more water particles, and respectively divide different types of boundary objects in the area to be simulated into two or more boundary particles;
  • a calculation module is configured to calculate a change in the position of each water particle over time using a hydrodynamic method based on the initial position of each of the water particles and the boundary particles.
  • the foregoing apparatus further includes:
  • the storage module is configured to save the calculated trend of the position of each of the water particles as a function of time.
  • the foregoing apparatus further includes:
  • the analysis module is configured to perform a dam break analysis according to the calculated change trend of the position of each of the water particles with time.
  • the foregoing apparatus further includes:
  • the display module is configured to perform three-dimensional dynamic visual display according to the calculated trend of the position of each of the water particles with time.
  • the calculating module is specifically configured to:
  • i denotes the water particles
  • j represents the boundary particle
  • p i is the pressure of the water particles i
  • w j is the boundary of the particle j
  • f bij is the volumetric force generated by the boundary particle j on the water particle i
  • ⁇ is the density of water
  • v i is the velocity of the water particle i
  • t time
  • the speed-to-time differential for the water particle i produced by f bij The acceleration of the water particle i
  • S i is the position of the water particle i
  • S 0i is the initial position of the water particle i
  • v 0i is the initial velocity of the water particle i.
  • Embodiments of the present invention include: dividing water in a region to be simulated into two or more water particles, respectively dividing different types of boundary objects in the region to be simulated into two or more boundary particles; according to each The initial positions of the water particles and the boundary particles are hydrodynamically calculated to calculate the tendency of the position of each water particle over time.
  • the motion process of the water particles is well simulated, so that the position of the water particles changes with time, and the precision of the simulation is improved.
  • FIG. 1 is a flow chart of a method for simulating a dam break according to an embodiment of the present invention
  • FIG. 2 is a schematic structural view of a device for simulating a dam break according to an embodiment of the present invention.
  • an embodiment of the present invention provides a method for simulating a dam break, comprising:
  • Step 100 Divide the water in the area to be simulated into two or more water particles, and respectively divide different types of boundary objects in the area to be simulated into two or more boundary particles.
  • the area to be simulated may be an area including a dam to be simulated.
  • the size of the area to be simulated can be determined according to the influence range of the flood after the dam break.
  • the boundary objects in the area to be simulated include terrain, roads, villages, trees, dams, and the like.
  • different types of boundary objects can be divided according to the influence of the boundary object on the motion of the water.
  • the boundary objects whose influence on the motion of the person is close can be attributed to the same type.
  • the water particles and the boundary particles are spheres.
  • the size of the divided water particles and boundary particles can be determined according to actual needs, and the smaller the diameter of the water particles and the boundary particles, the higher the precision of the simulation.
  • the specifics of the present invention are not specifically limited, and are not described herein.
  • Step 101 Calculate a change trend of the position of each water particle with time according to the initial position of each water particle and the boundary particle by a fluid dynamic method.
  • i denotes water particles
  • j denotes boundary particles
  • p i is the pressure of the water particle i
  • T i is the viscous stress tensor of the water particle i
  • w j is the weight of the boundary particle j
  • f bij is the boundary particle j to the water
  • ⁇ is the density of water
  • v i is the velocity of water particle i
  • t is time
  • the speed-to-time differential of the water particles produced by f bij The acceleration of the water particle i
  • S i is the position of the water particle i
  • S 0i is the initial position of the water particle i
  • v 0i is the initial velocity of the water particle i
  • ⁇ is the Hamiltonian
  • D is the differentiation of the vector.
  • w j is inversely proportional to the distance between the water particle i and the boundary particle j.
  • i denotes water particles
  • j denotes boundary particles
  • c is the speed of light
  • r ij is the distance between the boundary particle j and the water particle i
  • l is the radius of influence of the boundary particle
  • x ij is the boundary particle j and the water particle i The difference between the positions.
  • the motion process of the water particles is well simulated, so that the position of the water particles changes with time, and the precision of the simulation is improved.
  • the method further comprises: maintaining a trend of the position of each of the calculated water particles over time. Specifically, the correspondence between the identification of the water particles, the calculated position of the water particles, and the time can be saved.
  • the method further comprises: calculating the position of each water particle according to time according to time
  • the trend of change is analyzed by dam break. How to perform the dam break analysis is a well-known technique of the person skilled in the art, and is not intended to limit the scope of protection of the embodiments of the present invention, and details are not described herein again.
  • the method further comprises: performing a three-dimensional dynamic visual display according to the calculated trend of the position of each water particle with time.
  • the calculated trend of the position of each water particle with time can be visually displayed in three-dimensional dynamic order according to the time sequence, and the water particles are geometrically smooth and multi-level data compressed during the display process.
  • the details of the protection of the embodiments of the present invention are not limited herein, and are not described herein.
  • the three-dimensional dynamic visualization display enhances the intuitive analyzability of the simulated dam break.
  • Embodiments of the present invention also provide a computer readable storage medium storing computer executable instructions for performing the methods described above.
  • an embodiment of the present invention further provides a device for simulating a dam break, comprising:
  • a dividing module configured to divide water in the area to be simulated into two or more water particles, and respectively divide different types of boundary objects in the area to be simulated into two or more boundary particles;
  • a calculation module is configured to calculate a change in the position of each water particle over time using a hydrodynamic method based on the initial position of each of the water particles and the boundary particles.
  • the storage module is configured to save the calculated trend of the position of each water particle with time.
  • the analysis module is configured to perform dam break analysis according to the calculated trend of the position of each water particle with time.
  • the display module is configured to perform a three-dimensional dynamic visual display according to the calculated trend of the position of each water particle with time.
  • the calculation module is specifically configured to:
  • i denotes water particles
  • j denotes boundary particles
  • p i is the pressure of the water particle i
  • T i is the viscous stress tensor of the water particle i
  • w j is the weight of the boundary particle j
  • f bij is the boundary particle j to the water
  • ⁇ is the density of water
  • v i is the velocity of water particle i
  • t is time
  • the velocity-to-time differentiation of the water particle i produced by f bij The acceleration of the water particle i
  • S i is the position of the water particle i
  • S 0i is the initial position of the water particle i
  • v 0i is the initial velocity of the water particle i.
  • Embodiments of the present invention include: dividing water in a region to be simulated into two or more water particles, respectively dividing different types of boundary objects in the region to be simulated into two or more boundary particles; according to each The initial positions of the water particles and the boundary particles are hydrodynamically calculated to calculate the tendency of the position of each water particle over time.
  • the motion process of the water particles is well simulated, so that the position of the water particles changes with time, and the precision of the simulation is improved.

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Abstract

A method and apparatus for simulating dam-break, and a computer readable storage medium. The method comprises: dividing water in an area to be simulated into two or more water particles, and respectively dividing different types of boundary objects in the area to be simulated into two or more boundary particles (100); and using a fluid dynamics method to calculate a trend of a position of each water particle changing with time according to an initial position of each water particle and boundary particle (101).

Description

一种模拟溃坝的方法和装置以及计算机可读存储介质Method and device for simulating dam break and computer readable storage medium 技术领域Technical field
本文涉及地学模拟与地理信息技术领域。This paper covers the field of geoscience simulation and geographic information technology.
背景技术Background technique
近年来全球地质灾害频发，对类似于洪水溃坝这样的灾害的地学过程的模拟，融合了地学、计算机图形学、仿真计算、物理、数学等多个学科领域，是目前研究热点和难点。In recent years, global geological disasters have occurred frequently. The simulation of geosciences such as floods and dams has merged geosciences, computer graphics, simulation calculations, physics, mathematics and other disciplines. It is currently a hot topic and a difficult point.
现有技术中存在多种模拟溃坝的方法，例如，汇流分析方法、元胞自动机分析方法、多智能体分析方法等。以元胞自动机分析方法为例，现有的模拟溃坝的方法大致包括：将待模拟区块划分为多个网格，每一个网格包含有溃坝的影响因子，例如坡度、汇流量、作用方向等；当洪水进入网格时，根据网格中溃坝的影响因子按照预先设置的规则更新网格中的汇流量，并确定洪水的运动方向；模拟结束后根据网格中的汇流量对模拟结果进行分析。There are various methods for simulating a dam break in the prior art, for example, a sink analysis method, a cellular automaton analysis method, a multi-agent analysis method, and the like. Taking the cellular automaton analysis method as an example, the existing method for simulating the dam break generally includes dividing the block to be simulated into a plurality of grids, each grid containing influence factors of the dam break, such as slope and sink flow. When the flood enters the grid, according to the influence factor of the dam break in the grid, the flow in the grid is updated according to the preset rules, and the direction of the flood is determined; after the simulation is finished, according to the sink in the grid The flow analyzes the simulation results.
现有的模拟溃坝的方法中，由于预先设置的规则为人为规定，无法很好的模拟实际的溃坝过程，精度较低。In the existing method of simulating the dam break, since the preset rules are artificially specified, the actual dam break process cannot be well simulated, and the precision is low.
发明内容Summary of the invention
以下是对本文详细描述的主题的概述。本概述并非是为了限制权利要求的保护范围。(The following is a brief summary of subject matter that is described in greater detail herein.This summary is not intended to be limiting as to the scope of the claims.)The following is an overview of the topics detailed in this document. This Summary is not intended to limit the scope of the claims. (The following is a brief summary of subject matter that is described in greater detail herein. This summary is not intended to be limiting as to the scope of the claims.)
本发明实施例提出了一种模拟溃坝的方法和装置以及计算机可读存储介质，能够提高模拟精度。The embodiment of the invention provides a method and device for simulating a dam break and a computer readable storage medium, which can improve the simulation precision.
为了达到上述目的，本发明实施例提供一种模拟溃坝的方法，包括：In order to achieve the above object, an embodiment of the present invention provides a method for simulating a dam break, including:
将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子；Dividing the water in the area to be simulated into two or more water particles, respectively dividing the different types of boundary objects in the area to be simulated into two or more boundary particles;
根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一 个水粒子的位置随时间的变化趋势。Calculate each fluid dynamics method based on the initial position of each water particle and boundary particle The position of the water particles changes with time.
可选地，上述方法还包括：保存所述计算得到的每一个所述水粒子的位置随时间的变化趋势。Optionally, the method further includes: saving a trend of the position of each of the calculated water particles over time.
可选地，上述方法还包括：根据所述计算得到的每一个所述水粒子的位置随时间的变化趋势进行溃坝分析。Optionally, the method further includes: performing a dam break analysis according to the calculated trend of the position of each of the water particles over time.
可选地，上述方法还包括：根据所述计算得到的每一个所述水粒子的位置随时间的变化趋势进行三维动态可视化显示。Optionally, the method further includes: performing a three-dimensional dynamic visual display according to the calculated trend of the position of each of the water particles over time.
可选地，所述根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势包括：Optionally, the hydrodynamic method is used to calculate a change trend of the position of each water particle according to an initial position of each of the water particles and the boundary particles, including:
按照公式
Figure PCTCN2015078988-appb-000001
计算每一个所述水粒子的加速度；按照公式
Figure PCTCN2015078988-appb-000002
计算每一个所述水粒子的位置随时间的变化趋势；According to the formula
Figure PCTCN2015078988-appb-000001
Calculating the acceleration of each of the water particles; according to the formula
Figure PCTCN2015078988-appb-000002
Calculating a trend of the position of each of the water particles over time;
其中，i表示所述水粒子，j表示所述边界粒子，pi为所述水粒子i的压强，Ti为所述水粒子i的粘性应力张量，wj为所述边界粒子j的权重，fbij为所述边界粒子j对所述水粒子i产生的体积力，ρ为水的密度，
Figure PCTCN2015078988-appb-000003
为所述水粒子i的由fbij产生的速度，vi为所述水粒子i的速度，t为时间，
Figure PCTCN2015078988-appb-000004
为所述水粒子i的由fbij产生的速度对时间的微分，
Figure PCTCN2015078988-appb-000005
为所述水粒子i的加速度，Si为所述水粒子i的位置，S0i为所述水粒子i的初始位置，v0i为所述水粒子i的初始速度。Where, i denotes the water particles, j represents the boundary particle, p i is the pressure of the water particles i, T i of the viscous stress tensor water particle i, w j is the boundary of the particle j Weight, f bij is the volumetric force generated by the boundary particle j on the water particle i, and ρ is the density of water,
Figure PCTCN2015078988-appb-000003
For the velocity of the water particle i produced by f bij , v i is the velocity of the water particle i, t is time,
Figure PCTCN2015078988-appb-000004
The speed-to-time differential for the water particle i produced by f bij ,
Figure PCTCN2015078988-appb-000005
The acceleration of the water particle i, S i is the position of the water particle i, S 0i is the initial position of the water particle i, and v 0i is the initial velocity of the water particle i.
可选地，按照公式
Figure PCTCN2015078988-appb-000006
计算所述水粒子的由所述fbij产生的速度对时间的微分；Optionally, according to the formula
Figure PCTCN2015078988-appb-000006
 Calculating a differential of the velocity of the water particle produced by the f bij versus time;
其中，c为光速，rij为所述边界粒子j和所述水粒子i之间的距离，l为所述边界粒子的影响半径，xij为所述边界粒子j和所述水粒子i的位置之间的差值。Where c is the speed of light, r ij is the distance between the boundary particle j and the water particle i, l is the radius of influence of the boundary particle, and x ij is the boundary particle j and the water particle i The difference between the positions.
本发明实施例还提出了一种计算机可读存储介质，存储有计算机可执行 指令，所述计算机可执行指令用于执行上述任意一种模拟溃坝的方法。Embodiments of the present invention also provide a computer readable storage medium storing a computer executable An instruction to execute any of the above methods of simulating a dam breach.
本发明实施例还提出了一种模拟溃坝的装置，包括：The embodiment of the invention also provides a device for simulating a dam break, comprising:
划分模块，设置为将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子；a dividing module, configured to divide water in the area to be simulated into two or more water particles, and respectively divide different types of boundary objects in the area to be simulated into two or more boundary particles;
计算模块，设置为根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势。A calculation module is configured to calculate a change in the position of each water particle over time using a hydrodynamic method based on the initial position of each of the water particles and the boundary particles.
可选地，上述装置还包括：Optionally, the foregoing apparatus further includes:
存储模块，设置为保存计算得到的每一个所述水粒子的位置随时间的变化趋势。The storage module is configured to save the calculated trend of the position of each of the water particles as a function of time.
可选地，上述装置还包括：Optionally, the foregoing apparatus further includes:
分析模块，设置为根据计算得到的每一个所述水粒子的位置随时间的变化趋势进行溃坝分析。The analysis module is configured to perform a dam break analysis according to the calculated change trend of the position of each of the water particles with time.
可选地，上述装置还包括：Optionally, the foregoing apparatus further includes:
显示模块，设置为根据计算得到的每一个所述水粒子的位置随时间的变化趋势进行三维动态可视化显示。The display module is configured to perform three-dimensional dynamic visual display according to the calculated trend of the position of each of the water particles with time.
可选地，所述计算模块具体设置为：Optionally, the calculating module is specifically configured to:
按照公式
Figure PCTCN2015078988-appb-000007
计算每一个所述水粒子的加速度；按照公式
Figure PCTCN2015078988-appb-000008
计算每一个所述水粒子的位置随时间的变化趋势；According to the formula
Figure PCTCN2015078988-appb-000007
Calculating the acceleration of each of the water particles; according to the formula
Figure PCTCN2015078988-appb-000008
Calculating a trend of the position of each of the water particles over time;
其中，i表示所述水粒子，j表示所述边界粒子，pi为所述水粒子i的压强，Ti为所述水粒子i的粘性应力张量，wj为所述边界粒子j的权重，fbij为所述边界粒子j对所述水粒子i产生的体积力，ρ为水的密度，
Figure PCTCN2015078988-appb-000009
为所述水粒子i的由fbij产生的速度，vi为所述水粒子i的速度，t为时间，
Figure PCTCN2015078988-appb-000010
为所述水粒子i的由fbij产生的速度对时间的微分，
Figure PCTCN2015078988-appb-000011
为所述水粒子i的加速度，Si为所述水粒子i的位置，S0i为所述水粒子i的初始位置，v0i为所述水粒子i的初始速度。 Where, i denotes the water particles, j represents the boundary particle, p i is the pressure of the water particles i, T i of the viscous stress tensor water particle i, w j is the boundary of the particle j Weight, f bij is the volumetric force generated by the boundary particle j on the water particle i, and ρ is the density of water,
Figure PCTCN2015078988-appb-000009
For the velocity of the water particle i produced by f bij , v i is the velocity of the water particle i, t is time,
Figure PCTCN2015078988-appb-000010
The speed-to-time differential for the water particle i produced by f bij ,
Figure PCTCN2015078988-appb-000011
The acceleration of the water particle i, S i is the position of the water particle i, S 0i is the initial position of the water particle i, and v 0i is the initial velocity of the water particle i.
本发明实施例包括：将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子；根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势。通过本发明实施例的流体动力学方法，很好地模拟了水粒子的运动过程，从而很好地模拟了水粒子的位置随时间的变化趋势，进而提高了模拟的精度。Embodiments of the present invention include: dividing water in a region to be simulated into two or more water particles, respectively dividing different types of boundary objects in the region to be simulated into two or more boundary particles; according to each The initial positions of the water particles and the boundary particles are hydrodynamically calculated to calculate the tendency of the position of each water particle over time. Through the fluid dynamics method of the embodiment of the invention, the motion process of the water particles is well simulated, so that the position of the water particles changes with time, and the precision of the simulation is improved.
在阅读并理解了附图和详细描述后，可以明白其他方面。(Other aspects will be appreciated upon reading and understanding the attached figures and detailed description)Other aspects will be apparent upon reading and understanding the drawings and detailed description. (Other aspects will be appreciated upon reading and understanding the attached figures and detailed description)
附图概述BRIEF abstract
图1为本发明实施例模拟溃坝的方法的流程图；1 is a flow chart of a method for simulating a dam break according to an embodiment of the present invention;
图2为本发明实施例模拟溃坝的装置的结构组成示意图。FIG. 2 is a schematic structural view of a device for simulating a dam break according to an embodiment of the present invention.
本发明的较佳实施方式Preferred embodiment of the invention
参见图1，本发明实施例提出了一种模拟溃坝的方法，包括：Referring to FIG. 1, an embodiment of the present invention provides a method for simulating a dam break, comprising:
步骤100、将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子。Step 100: Divide the water in the area to be simulated into two or more water particles, and respectively divide different types of boundary objects in the area to be simulated into two or more boundary particles.
本步骤中，待模拟区域可以是包含待模拟大坝在内的区域。待模拟区域的大小可以根据溃坝后洪水的影响范围来确定。In this step, the area to be simulated may be an area including a dam to be simulated. The size of the area to be simulated can be determined according to the influence range of the flood after the dam break.
本步骤中，待模拟区域内的边界对象包括地形，道路、村庄、树木、坝体等。具体可以根据边界对象对水的运动的影响来划分不同类型的边界对象，例如可以将对谁的运动的影响接近的边界对象归结为同一种类型。In this step, the boundary objects in the area to be simulated include terrain, roads, villages, trees, dams, and the like. Specifically, different types of boundary objects can be divided according to the influence of the boundary object on the motion of the water. For example, the boundary objects whose influence on the motion of the person is close can be attributed to the same type.
本步骤中，水粒子和边界粒子为球体。In this step, the water particles and the boundary particles are spheres.
本步骤中，划分后水粒子和边界粒子的大小可以根据实际需要来确定，水粒子和边界粒子的直径越小，模拟的精度越高。具体如何划分属于本领域技术人员的公知技术，并不用于限定本发明的保护范围，这里不再赘述。In this step, the size of the divided water particles and boundary particles can be determined according to actual needs, and the smaller the diameter of the water particles and the boundary particles, the higher the precision of the simulation. The specifics of the present invention are not specifically limited, and are not described herein.
步骤101、根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势。 Step 101: Calculate a change trend of the position of each water particle with time according to the initial position of each water particle and the boundary particle by a fluid dynamic method.
具体地，按照公式
Figure PCTCN2015078988-appb-000012
计算每一个水粒子的加速度；按照公式
Figure PCTCN2015078988-appb-000013
计算每一个水粒子的位置随时间的变化趋势；Specifically, according to the formula
Figure PCTCN2015078988-appb-000012
Calculate the acceleration of each water particle;
Figure PCTCN2015078988-appb-000013
Calculate the trend of the position of each water particle over time;
其中，i表示水粒子，j表示边界粒子，pi为水粒子i的压强，Ti为水粒子i的粘性应力张量，wj为边界粒子j的权重，fbij为边界粒子j对水粒子i产生的体积力，ρ为水的密度，
Figure PCTCN2015078988-appb-000014
为水粒子的由fbij产生的速度，vi为水粒子i的速度，t为时间，
Figure PCTCN2015078988-appb-000015
为水粒子的由fbij产生的速度对时间的微分，
Figure PCTCN2015078988-appb-000016
为水粒子i的加速度，Si为水粒子i的位置，S0i为水粒子i的初始位置，v0i为水粒子i的初始速度，▽为哈密顿算子，D表示对矢量的微分。Where i denotes water particles, j denotes boundary particles, p i is the pressure of the water particle i, T i is the viscous stress tensor of the water particle i, w j is the weight of the boundary particle j, and f bij is the boundary particle j to the water The volumetric force produced by particle i, ρ is the density of water,
Figure PCTCN2015078988-appb-000014
For the velocity of water particles produced by f bij , v i is the velocity of water particle i, t is time,
Figure PCTCN2015078988-appb-000015
The speed-to-time differential of the water particles produced by f bij ,
Figure PCTCN2015078988-appb-000016
The acceleration of the water particle i, S i is the position of the water particle i, S 0i is the initial position of the water particle i, v 0i is the initial velocity of the water particle i, ▽ is the Hamiltonian, and D is the differentiation of the vector.
其中，wj与水粒子i和边界粒子j之间的距离成反比。Where w j is inversely proportional to the distance between the water particle i and the boundary particle j.
其中，按照公式
Figure PCTCN2015078988-appb-000017
计算水粒子i的由fbij产生的速度对时间的微分；Among them, according to the formula
Figure PCTCN2015078988-appb-000017
 Calculating the speed-to-time differential of the water particle i produced by f bij ;
其中，i表示水粒子，j表示边界粒子，c为光速，rij为边界粒子j和水粒子i之间的距离，l为边界粒子的影响半径，xij为边界粒子j和水粒子i的位置之间的差值。Where i denotes water particles, j denotes boundary particles, c is the speed of light, r ij is the distance between the boundary particle j and the water particle i, l is the radius of influence of the boundary particle, and x ij is the boundary particle j and the water particle i The difference between the positions.
其中，具体如何计算pi和Ti属于本领域技术人员的公知技术，并不用于限定本发明的保护范围，这里不再赘述。Wherein, specifically how to calculate p i T i of the techniques known in the art belonging to the art, and are not intended to limit the scope of the present invention and will not be repeated here.
本步骤中，具体如何获取每一个水粒子和边界粒子的位置属于本领域技术人员的公知技术，并不用于限定本发明实施例的保护范围，这里不再赘述。In this step, how to obtain the position of each of the water particles and the boundary particles is specifically known to those skilled in the art, and is not intended to limit the scope of protection of the embodiments of the present invention, and details are not described herein again.
通过本发明实施例中的流体动力学方法，很好地模拟了水粒子的运动过程，从而很好地模拟了水粒子的位置随时间的变化趋势，进而提高了模拟的精度。Through the fluid dynamics method in the embodiment of the invention, the motion process of the water particles is well simulated, so that the position of the water particles changes with time, and the precision of the simulation is improved.
可选地，该方法还包括：保存计算得到的每一个水粒子的位置随时间的变化趋势。具体地，可以保存水粒子的标识、计算得到的水粒子的位置、时间之间的对应关系。Optionally, the method further comprises: maintaining a trend of the position of each of the calculated water particles over time. Specifically, the correspondence between the identification of the water particles, the calculated position of the water particles, and the time can be saved.
可选地，该方法还包括：根据计算得到的每一个水粒子的位置随时间的 变化趋势进行溃坝分析。具体如何进行溃坝分析属于本领域技术人员的公知技术，并不用于限定本发明实施例的保护范围，这里不再赘述。Optionally, the method further comprises: calculating the position of each water particle according to time according to time The trend of change is analyzed by dam break. How to perform the dam break analysis is a well-known technique of the person skilled in the art, and is not intended to limit the scope of protection of the embodiments of the present invention, and details are not described herein again.
可选地，该方法还包括：根据计算得到的每一个水粒子的位置随时间的变化趋势进行三维动态可视化显示。Optionally, the method further comprises: performing a three-dimensional dynamic visual display according to the calculated trend of the position of each water particle with time.
具体地，可以将计算得到的每一个水粒子的位置随时间的变化趋势按照时间的先后顺序进行三维动态可视化显示，在显示过程中对水粒子进行几何光滑和多级数据压缩。具体如何实现属于本领域技术人员的公知技术，并不用于限定本发明实施例的保护范围，这里不再赘述。Specifically, the calculated trend of the position of each water particle with time can be visually displayed in three-dimensional dynamic order according to the time sequence, and the water particles are geometrically smooth and multi-level data compressed during the display process. The details of the protection of the embodiments of the present invention are not limited herein, and are not described herein.
其中，进行三维动态可视化显示增强了模拟溃坝的直观可分析性。Among them, the three-dimensional dynamic visualization display enhances the intuitive analyzability of the simulated dam break.
本发明实施例还提出了一种计算机可读存储介质，存储有计算机可执行指令，计算机可执行指令用于执行上述描述的方法。Embodiments of the present invention also provide a computer readable storage medium storing computer executable instructions for performing the methods described above.
参见图2，本发明实施例还提出了一种模拟溃坝的装置，包括：Referring to FIG. 2, an embodiment of the present invention further provides a device for simulating a dam break, comprising:
划分模块，设置为将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子；a dividing module, configured to divide water in the area to be simulated into two or more water particles, and respectively divide different types of boundary objects in the area to be simulated into two or more boundary particles;
计算模块，设置为根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势。A calculation module is configured to calculate a change in the position of each water particle over time using a hydrodynamic method based on the initial position of each of the water particles and the boundary particles.
本发明实施例的装置中，还包括：The device of the embodiment of the present invention further includes:
存储模块，设置为保存计算得到的每一个水粒子的位置随时间的变化趋势。The storage module is configured to save the calculated trend of the position of each water particle with time.
本发明实施例的装置中，还包括：The device of the embodiment of the present invention further includes:
分析模块，设置为根据计算得到的每一个水粒子的位置随时间的变化趋势进行溃坝分析。The analysis module is configured to perform dam break analysis according to the calculated trend of the position of each water particle with time.
本发明实施例的装置中，还包括：The device of the embodiment of the present invention further includes:
显示模块，设置为根据计算得到的每一个水粒子的位置随时间的变化趋势进行三维动态可视化显示。The display module is configured to perform a three-dimensional dynamic visual display according to the calculated trend of the position of each water particle with time.
本发明实施例的装置中，计算模块具体设置为： In the apparatus of the embodiment of the present invention, the calculation module is specifically configured to:
按照公式
Figure PCTCN2015078988-appb-000018
计算每一个水粒子的加速度；按照公式
Figure PCTCN2015078988-appb-000019
计算每一个水粒子的位置随时间的变化趋势；According to the formula
Figure PCTCN2015078988-appb-000018
Calculate the acceleration of each water particle;
Figure PCTCN2015078988-appb-000019
Calculate the trend of the position of each water particle over time;
其中，i表示水粒子，j表示边界粒子，pi为水粒子i的压强，Ti为水粒子i的粘性应力张量，wj为边界粒子j的权重，fbij为边界粒子j对水粒子i产生的体积力，ρ为水的密度，
Figure PCTCN2015078988-appb-000020
为水粒子i的由fbij产生的速度，vi为水粒子i的速度，t为时间，
Figure PCTCN2015078988-appb-000021
为水粒子i的由fbij产生的速度对时间的微分，
Figure PCTCN2015078988-appb-000022
为水粒子i的加速度，Si为水粒子i的位置，S0i为水粒子i的初始位置，v0i为水粒子i的初始速度。Where i denotes water particles, j denotes boundary particles, p i is the pressure of the water particle i, T i is the viscous stress tensor of the water particle i, w j is the weight of the boundary particle j, and f bij is the boundary particle j to the water The volumetric force produced by particle i, ρ is the density of water,
Figure PCTCN2015078988-appb-000020
For the velocity of water particle i produced by f bij , v i is the velocity of water particle i, t is time,
Figure PCTCN2015078988-appb-000021
The velocity-to-time differentiation of the water particle i produced by f bij ,
Figure PCTCN2015078988-appb-000022
The acceleration of the water particle i, S i is the position of the water particle i, S 0i is the initial position of the water particle i, and v 0i is the initial velocity of the water particle i.
工业实用性Industrial applicability
本发明实施例包括：将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子；根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势。通过本发明实施例的流体动力学方法，很好地模拟了水粒子的运动过程，从而很好地模拟了水粒子的位置随时间的变化趋势，进而提高了模拟的精度。 Embodiments of the present invention include: dividing water in a region to be simulated into two or more water particles, respectively dividing different types of boundary objects in the region to be simulated into two or more boundary particles; according to each The initial positions of the water particles and the boundary particles are hydrodynamically calculated to calculate the tendency of the position of each water particle over time. Through the fluid dynamics method of the embodiment of the invention, the motion process of the water particles is well simulated, so that the position of the water particles changes with time, and the precision of the simulation is improved.

Claims (12)

  1. 一种模拟溃坝的方法，包括：A method of simulating a dam break, comprising:
    将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子；Dividing the water in the area to be simulated into two or more water particles, respectively dividing the different types of boundary objects in the area to be simulated into two or more boundary particles;
    根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势。The hydrodynamic method is used to calculate the change trend of the position of each water particle with time according to the initial position of each water particle and boundary particle.
  2. 根据权利要求1所述的方法，还包括：保存所述计算得到的每一个所述水粒子的位置随时间的变化趋势。The method of claim 1 further comprising: maintaining a trend of the position of each of said calculated water particles over time.
  3. 根据权利要求1所述的方法，还包括：根据所述计算得到的每一个所述水粒子的位置随时间的变化趋势进行溃坝分析。The method of claim 1, further comprising: performing a dam analysis based on the calculated trend of the position of each of the water particles over time.
  4. 根据权利要求1所述的方法，还包括：根据所述计算得到的每一个所述水粒子的位置随时间的变化趋势进行三维动态可视化显示。The method of claim 1, further comprising: performing a three-dimensional dynamic visual display based on the calculated trend of the position of each of the water particles over time.
  5. 根据权利要求1～4任意一项所述的方法，其中：A method according to any one of claims 1 to 4, wherein:
    所述根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势包括：The hydrodynamic method for calculating the position of each water particle according to the initial position of each of the water particles and the boundary particles with time includes:
    按照公式
    Figure PCTCN2015078988-appb-100001
    计算每一个所述水粒子的加速度；按照公式
    Figure PCTCN2015078988-appb-100002
    计算每一个所述水粒子的位置随时间的变化趋势；    According to the formula
    Figure PCTCN2015078988-appb-100001
    Calculating the acceleration of each of the water particles; according to the formula
    Figure PCTCN2015078988-appb-100002
    Calculating a trend of the position of each of the water particles over time;
    其中，i表示所述水粒子，j表示所述边界粒子，pi为所述水粒子i的压强，Ti为所述水粒子i的粘性应力张量，wj为所述边界粒子j的权重，fbij为所述边界粒子j对所述水粒子i产生的体积力，ρ为水的密度，
    Figure PCTCN2015078988-appb-100003
    为所述水粒子i的由fbij产生的速度，vi为所述水粒子i的速度，t为时间，
    Figure PCTCN2015078988-appb-100004
    为所述水粒子i的由fbij产生的速度对时间的微分，
    Figure PCTCN2015078988-appb-100005
    为所述水粒子i的加速度，Si为所述水粒子i的位置，S0i为所述水粒子i的初始位置，v0i为所述水粒子i的初始速度。    Where, i denotes the water particles, j represents the boundary particle, p i is the pressure of the water particles i, T i of the viscous stress tensor water particle i, w j is the boundary of the particle j Weight, f bij is the volumetric force generated by the boundary particle j on the water particle i, and ρ is the density of water,
    Figure PCTCN2015078988-appb-100003
    For the velocity of the water particle i produced by f bij , v i is the velocity of the water particle i, t is time,
    Figure PCTCN2015078988-appb-100004
    The speed-to-time differential for the water particle i produced by f bij ,
    Figure PCTCN2015078988-appb-100005
    The acceleration of the water particle i, S i is the position of the water particle i, S 0i is the initial position of the water particle i, and v 0i is the initial velocity of the water particle i.
  6. 根据权利要求5所述的方法，其中： The method of claim 5 wherein:
    按照公式
    Figure PCTCN2015078988-appb-100006
    计算所述水粒子的由所述fbij产生的速度对时间的微分；    According to the formula
    Figure PCTCN2015078988-appb-100006
     Calculating a differential of the velocity of the water particle produced by the f bij versus time;
    其中，c为光速，rij为所述边界粒子j和所述水粒子i之间的距离，l为所述边界粒子的影响半径，xij为所述边界粒子j和所述水粒子i的位置之间的差值。Where c is the speed of light, r ij is the distance between the boundary particle j and the water particle i, l is the radius of influence of the boundary particle, and x ij is the boundary particle j and the water particle i The difference between the positions.
  7. 一种计算机可读存储介质，存储有计算机可执行指令，所述计算机可执行指令用于执行权利要求1-6任一项的方法。A computer readable storage medium storing computer executable instructions for performing the method of any of claims 1-6.
  8. 一种模拟溃坝的装置，包括：A device for simulating a dam break, comprising:
    划分模块，设置为将待模拟区域内的水划分为两个或两个以上水粒子，分别将待模拟区域内的不同类型的边界对象划分为两个或两个以上边界粒子；a dividing module, configured to divide water in the area to be simulated into two or more water particles, and respectively divide different types of boundary objects in the area to be simulated into two or more boundary particles;
    计算模块，设置为根据每一个水粒子和边界粒子的初始位置采用流体动力学方法计算每一个水粒子的位置随时间的变化趋势。A calculation module is configured to calculate a change in the position of each water particle over time using a hydrodynamic method based on the initial position of each of the water particles and the boundary particles.
  9. 根据权利要求8所述的装置，还包括：The apparatus of claim 8 further comprising:
    存储模块，设置为保存计算得到的每一个所述水粒子的位置随时间的变化趋势。The storage module is configured to save the calculated trend of the position of each of the water particles as a function of time.
  10. 根据权利要求8所述的装置，还包括：The apparatus of claim 8 further comprising:
    分析模块，设置为根据计算得到的每一个所述水粒子的位置随时间的变化趋势进行溃坝分析。The analysis module is configured to perform a dam break analysis according to the calculated change trend of the position of each of the water particles with time.
  11. 根据权利要求8所述的装置，还包括：The apparatus of claim 8 further comprising:
    显示模块，设置为根据计算得到的每一个所述水粒子的位置随时间的变化趋势进行三维动态可视化显示。The display module is configured to perform three-dimensional dynamic visual display according to the calculated trend of the position of each of the water particles with time.
  12. 根据权利要求8～11任意一项所述的装置，所述计算模块具体设置为：The device according to any one of claims 8 to 11, wherein the calculation module is specifically configured to:
    按照公式
    Figure PCTCN2015078988-appb-100007
    计算每一个所述水粒子的加速 度；按照公式
    Figure PCTCN2015078988-appb-100008
    计算每一个所述水粒子的位置随时间的变化趋势；    According to the formula
    Figure PCTCN2015078988-appb-100007
    Calculating the acceleration of each of the water particles; according to the formula
    Figure PCTCN2015078988-appb-100008
    Calculating a trend of the position of each of the water particles over time;
    其中，i表示所述水粒子，j表示所述边界粒子，pi为所述水粒子i的压强，Ti为所述水粒子i的粘性应力张量，wj为所述边界粒子j的权重，fbij为所述边界粒子j对所述水粒子i产生的体积力，ρ为水的密度，
    Figure PCTCN2015078988-appb-100009
    为所述水粒子i的由fbij产生的速度，vi为所述水粒子i的速度，t为时间，
    Figure PCTCN2015078988-appb-100010
    为所述水粒子i的由fbij产生的速度对时间的微分，
    Figure PCTCN2015078988-appb-100011
    为所述水粒子i的加速度，Si为所述水粒子i的位置，S0i为所述水粒子i的初始位置，v0i为所述水粒子i的初始速度。     Where, i denotes the water particles, j represents the boundary particle, p i is the pressure of the water particles i, T i of the viscous stress tensor water particle i, w j is the boundary of the particle j Weight, f bij is the volumetric force generated by the boundary particle j on the water particle i, and ρ is the density of water,
    Figure PCTCN2015078988-appb-100009
    For the velocity of the water particle i produced by f bij , v i is the velocity of the water particle i, t is time,
    Figure PCTCN2015078988-appb-100010
    The speed-to-time differential for the water particle i produced by f bij ,
    Figure PCTCN2015078988-appb-100011
    The acceleration of the water particle i, S i is the position of the water particle i, S 0i is the initial position of the water particle i, and v 0i is the initial velocity of the water particle i.
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