虚拟流域技术及其在数字湖泊工程中的应用

发布时间：2018-07-10 17:43

本文选题：虚拟流域 + 数字流域　；参考：《华中科技大学》2014年博士论文

【摘要】：随着对水利工程建设和流域水资源管理要求的不断提高,水资源管理决策支持系统正朝着智能化、可视化的方向发展,水资源管理决策支持理论是集系统工程学、水动力学、虚拟现实和空间信息科学等多学科的交叉研究领域,通过对工程数据、业务模型和高维信息的虚拟可视化进行有效集成,可以直观的展示实时计算结果、充分揭示不同条件下水动力学响应机制,为流域水资源和水利工程管理提供有效的数据支撑和智能决策。在基于虚拟流域的水资源决策支持系统中,流体仿真具有非常重要的地位。逼真的流体不但可以增加仿真的真实感,而且可以耦合后台计算模型的基础上,充分表征如淹没范围、水位、水深、流速等动态水流流态及其响应机制。然而,基于物理的流体计算具有高维度、非线性等特点,在实施大面积流域仿真的过程中,其计算复杂度呈几何级数增长,如何构建虚拟流域仿真中高效求解计算框架,充分挖掘计算资源、实现软硬件混合并行加速计算,已成为流域仿真和水资源管理决策支持系统中亟需解决的科学问题和技术瓶颈。另一方面,由于流域水资源是一类受多种因素影响的复杂系统,且流域水资源管理决策过程涉及社会、经济、水文、水动、水工和生态等多个领域,具有海量的异构数据,拥有气象、水文、洪水、评价等多种专业模型,当前大多系统虽然已经对各个专业模型构建了基本的业务系统,但是由于当前水资源管理决策多系统集成理论的滞后,各个系统之间存在信息孤岛,数据冗余且难以交互,各个业务之间无法进行协同计算,从而导致水资源管理系统的业务无法高效准确的应用于工程实践当中,因此,探究水资源管理系统的多业务柔性集成方法,构建具有高度可扩展性的综合异构数字仿真平台,充分实现水资源合理优化高效配置、提供决策支持服务,是当前水利工程建设和管理过程中迫切需要解决的问题,具有非常重要的科学意义和工程实用价值。本文围绕软硬件混合并行虚拟流域仿真的高效求解及在水利工程中的应用问题,以国家“973”重点基础研究发展计划课题和水利部公益性行业科研专项等研究任务为依托,在充分研究了流体仿真的基本原理、基于软硬件混合并行加速的原理和实现框架基础上、提出了虚拟流域仿真数字平台的构建理论和方法,建立了基于流体仿真的虚拟流域综合数字平台体系,实现了大型湖泊海洋的多维信息可视化,并将相关研究成果应用到实际水利工程项目之中,为我国水利工程运行管理人员提供了有效的理论与技术支持。本文的主要研究工作和创新点包括： (1)针对基于物理的流体仿真求解耗时的难题,重点探讨了光滑粒子动力学方法(Smoothed Particle Hydrodynamics,SPH)流体仿真问题,提出了一种改进的最近邻居粒子搜索算法,实现了时间和空间相关的最近邻居粒子搜索,显著提高了搜索的效率。采用CUDA(Compute Unified Device Architecture)架构实现了SPH改进算法的硬件并行加速,显著提高了仿真的速度,满足实时应用的需要。 (2)基于物理的流体仿真主要应用在小规模、小尺度范围地形上,为了实现大范围地形上、大尺度流域仿真,提出了基于CUDA架构的B6zier曲线和流线法向贴图的河流仿真方法。该方法使用四边形对河流流域进行划分,采用Bezier曲线描述河流的走向,把河流区域的像素投射在曲线上执行渲染。在保证逼真渲染效果的同时,显著提高了系统的运行速度,能满足复杂河网情况下的河流实时仿真。 (3)基于频谱统计海洋模型,在考虑风速、风向等风场数据对波浪形态的影响下,首次实现了基于CUDA和Phillips海浪谱的大面积流域仿真方法,实现了对湖泊和海洋的精细化模拟。同时,针对一般仿真系统集成度不高,开发时间过长等问题,提出了综合C++/CLI技术、OpenSceneGraph(OSG)和频谱模型的COSG三维数字湖泊仿真快速开发方法,并将其应用到了实际工程应用中。同时深入分析湖泊和海洋水面波长的不同特征,针对当前基于CUDA的湖泊仿真中未考虑波长影响的不足,提出了一种综合投影网格和改进Perlin噪声方法的改进数字湖泊仿真方法,解决了基于CUDA的高效湖泊仿真计算问题。 (4)在上节提出的COSG三维数字湖泊的快速开发方法基础上,结合水动力学分布式湖流计算模型和水质模型,实现了风生流场的三维仿真和水质污染扩散的动态展示。为解决虚拟流域仿真和水资源管理决策支持系统的中多业务协同和信息交互的实际问题,提出了基于COSG和松耦合模型驱动技术的数字流域平台框架构建理论与方法,构建了大东湖虚拟城市湖泊数字化平台,并应用于大东湖水网调度实际工程中。 (5)针对大范围地形上基于物理流体的流域仿真建模中实时仿真面临的计算资源瓶颈,提出了基于水动力学模型和GIS组动画技术的三维洪水演进可视化仿真方法。并构建了持续集成的松耦合模型驱动集成框架,实现了三维洪水演进可视化和“坝堤溃决决策支持系统”的有效集成,并将该系统应用在国家“973”重点基础研究发展计划课题示范平台之中。
[Abstract]:With the continuous improvement of water conservancy construction and water resource management, the decision support system of water resources management is developing towards intelligent and visual direction. The theory of decision support for water resources management is a cross research field of system engineering, hydrodynamics, virtual reality and space information science. The effective integration of process data, business model and virtual visualization of high dimensional information can display the real-time calculation results intuitively, fully reveal the dynamic response mechanism of different conditions, and provide effective data support and intelligent decision for water resources and water conservancy project management in the basin. The water resource decision support system based on virtual River Basin Fluid simulation has a very important position. Realistic fluid not only can increase the realistic sense of simulation, but also can fully characterize the dynamic flow patterns, such as the submerged range, water level, water depth and flow velocity, and its response mechanism on the basis of coupling the background calculation model. However, the physical fluid calculation is characterized by high dimension, nonlinear and so on. In the process of implementing large area watershed simulation, the computational complexity is increasing geometrically. How to construct the efficient calculation framework in the virtual basin simulation, fully excavate the computing resources and realize the mixed parallel acceleration calculation of hardware and software has become a scientific problem which needs to be solved urgently in the decision support system of river basin simulation and water resources management. On the other hand, the water resource of the basin is a kind of complex system which is influenced by many factors, and the decision-making process of water resource management in the basin involves many fields, such as social, economic, hydrological, hydrodynamic, hydraulic and ecological. It has a large number of heterogeneous data and many kinds of professional models, such as meteorology, hydrology, flood, evaluation and so on. Most of the systems are currently in the system. Although the basic business system has been built for various professional models, because of the lag of the theory of multi system integration in the decision making of water resource management, there are isolated information islands in each system, the data is redundant and difficult to interact, and the cooperative computing can not be carried out among the various services, which leads to the failure of the business of the water resource management system to be efficient. It is true that it is applied to engineering practice. Therefore, it is urgent to explore the multi business flexible integration method of water resource management system, build a comprehensive heterogeneous digital simulation platform with high scalability, fully realize the rational and efficient allocation of water resources, and provide decision support services. It is an urgent need to solve the current construction and management of water conservancy projects. The problem is of great scientific significance and practical engineering value.
This paper focuses on the efficient solution of hardware and software hybrid parallel virtual watershed simulation and its application in water conservancy projects. Based on the research task of national "973" key basic research and development plan and the research task of the Ministry of water resources in the Ministry of water resources, the basic principle of fluid simulation is fully studied, and the mixed parallel addition of hardware and software is based on the hardware and software. On the basis of speed principle and realization framework, the theory and method of constructing virtual basin simulation digital platform are put forward, and a comprehensive digital platform system based on fluid simulation is established to realize multidimensional information visualization of large lakes and oceans, and the related research results should be used in the actual water conservancy project and water conservancy in China. The project management personnel provide effective theoretical and technical support. The main research work and innovation of this paper include:
(1) to solve the time-consuming problem of fluid simulation based on physical fluid simulation, the problem of Smoothed Particle Hydrodynamics (SPH) fluid simulation is discussed. An improved nearest neighbor particle search algorithm is proposed. The nearest neighbor particle search of time and space is realized, and the efficiency of search is greatly improved. Using the architecture of CUDA (Compute Unified Device Architecture), the hardware parallel acceleration of the improved SPH algorithm is realized, and the speed of the simulation is greatly improved and the needs of the real-time application are met.
(2) physical fluid simulation is mainly used in small scale and small scale terrain. In order to realize large scale terrain and large scale basin simulation, a river simulation method based on B6zier curve and streamline method based on CUDA architecture is proposed. The method uses quadrilateral to divide River Basin and describes rivers with Bezier curve. The direction of the river region is projected on the curve to perform the rendering. While ensuring the realistic rendering effect, it can significantly improve the running speed of the system, and can meet the real-time simulation of the river in the complex river network.
(3) based on the spectrum statistics ocean model, the large area simulation method based on CUDA and Phillips wave spectrum is realized for the first time under the influence of wind speed, wind direction and other wind field data on the wave form, and the fine simulation of lakes and oceans is realized. At the same time, the problems of low integration degree and long development time are proposed. The rapid development method of integrated C++/CLI technology, OpenSceneGraph (OSG) and spectrum model of COSG three-dimensional digital Lake simulation was developed and applied to practical engineering applications. At the same time, the different characteristics of the wavelengths of the lake and the sea surface were analyzed, and the lack of wavelength influence in the current CUDA based Lake simulation was put forward. An improved digital Lake simulation method based on integrated projection grid and improved Perlin noise method has solved the problem of CUDA based efficient Lake simulation.
(4) on the basis of the rapid development method of COSG three-dimensional digital lakes proposed in the last section, combined with the hydrodynamic distribution lake flow calculation model and the water quality model, the three-dimensional simulation of the wind flow field and the dynamic display of the water pollution diffusion are realized. In order to solve the multi service collaboration and the letter of the decision support system for the virtual basin simulation and the water resource management, the multi service cooperation and the letter are used. The theory and method of building the framework of digital basin platform based on COSG and loosely coupled model driving technology are put forward, and the digital platform of East Lake Virtual City Lake is constructed, and it is applied to the actual project of the large East Lake water network scheduling.
(5) a three-dimensional flood evolution visualization simulation method based on hydrodynamics model and GIS group animation technology is proposed in view of the bottleneck of real-time simulation in the simulation modeling of large scale terrain based on physical fluid, and the integrated framework of loosely coupled model driving is constructed, which realizes the three dimensional flood evolution. The effective integration of visualization and "decision support system for dam break" is effectively applied to the national "973" key basic research and development project demonstration platform.
【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TV213.4-39

【参考文献】