摘 要 方腔流作为测试算法性能的基本问题之一，以具备较为简单的结构和边界条件并且包含了几乎所有紊流特征会出现的现象而被广泛关注。OpenFOAM作为开源CFD软件，其特点之一就是利用有限体积法去求解分析流体问题。最近几年，OpenFOAM越来越多的被应用到工程实际问题的解决当中。其中的应用程序之一求解器是为了解决特定的连续介质力学问题所设计的。在这项工作中我们在开源CFD软件OpenFOAM中实现了对二维不可压缩方腔顶盖驱动流的模拟工作。首先通过给出导热微分方程和定解条件实现了对方腔流的数学描述，然后通过改写、重新编译求解器在OpenFOAM中实现对方腔流的温度模拟，通过分析对比温度云图，可以看出随着时间的变化，热量不断的从方腔外部向内部扩散，并且由于涡流的原因，方腔右上角的传热速率明显要快于其它方向。在此基础上，进行网格细化和网格非均匀化的研究工作，可以看出这两项工作都可以使得模拟解更加趋向于解析解，使得模拟过程清晰化，模拟结论具有更高的准确性。 关键词：方腔流；OpenFOAM；温度模拟；网格细化；网格非均匀化 Abstract As one of the basic problems in the performance of the test algorithm, the cavity flow is widely concerned with relatively simple structure and boundary conditions and including almost all the phenomena of turbulence characteristics. One of the characteristics of OpenFOAM as an open source CFD software is to use the finite volume method to solve fluid analysis problems. In recent years, more and more OpenFOAM has been applied to solve practical engineering problems. One of the application solvers is designed to solve specific continuous mechanics problems. In this work, we realized the simulation of two-dimensional incompressible cavity top cover driving flow in open source CFD software OpenFOAM. Firstly, the mathematical description of the cavity flow is realized by giving the differential equation of heat conduction and the definite solution conditions. Then, by rewriting and recompiling the solver, the temperature simulation of the opposing cavity flow is realized in OpenFOAM. By analyzing and comparing the temperature cloud diagrams, it can be seen that with the change of time, the heat continuously spreads from the outside to the inside of the cavity, and due to the eddy current The heat transfer rate in the upper right corner of the cavity is significantly faster than in other directions. On this basis, the research work on grid refinement and grid non-uniformization can be seen that both of these tasks can make the simulation solution more apt to analytical solutions, making the simulation process clearer and the simulation conclusions higher accuracy. Key Words: cavity flow; OpenFOAM; Temperature simulation; grid refinement; grid non-uniformity 目 录 第1章 绪论.................................................................................................................................1 1.1 研究背景........................................................................................................................1 1.2 研究现状........................................................................................................................1 1.3 研究内容与方法............................................................................................................3 1.4 本章小结........................................................................................................................4 第2章 数值方法基本理论.........................................................................................................5 2.1 导热微分方程................................................................................................................5 2.2 定解条件........................................................................................................................6 2.3 本章小结........................................................................................................................6 第3章 基于OpenFOAM的模型建立.....................................................................................7 3.1 OpenFOAM的特点.......................................................................................................7 3.2 OpenFOAM编程语言...................................................................................................8 3.2.1 面向对象和C .................................................................................................8 3.2.2 方程呈现.............................................................................................................8 3.3 OpenFOAM运行流程.................................................................................................9 3.4 算例求解步骤(以方腔流压力场模拟为例)................................................................9 3.4.1 前处理...............................................................................................................10 3.4.2 运行算例...........................................................................................................10 3.4.3 后处理...............................................................................................................10 3.5 本章小结......................................................................................................................11 第4章 基于OpenFOAM的方腔流温度模拟...................................................................12 4.1 求解器源代码的改写和编译......................................................................................13 4.1.1 准备工作...........................................................................................................13 4.1.2 创建新物性和新变量场...................................................................................13 4.1.3 加入新的温度求解方程...................................................................................14 4.2 前处理..........................................................................................................................14 4.2.1 网格的生成.......................................................................................................14 4.2.1.1 缩放因子................................................................................................15 4.2.1.2 点............................................................................................................15 4.2.1.3 边............................................................................................................16 4.2.1.4 块............................................................................................................17 4.2.2 边界条件...........................................................................................................19 4.2.3 物理特性...........................................................................................................20 4.2.4 控制...................................................................................................................20 4.2.5 离散格式的设定...............................................................................................21 4.2.6 求解器和算法控制...........................................................................................23 4.3 运行算例......................................................................................................................24 4.4 后处理..........................................................................................................................24 4.5 温度场模拟云图及分析..............................................................................................24 4.5.1 无内热源均匀化网格下的温度云图...............................................................25 4.5.2 有内热源下的温度云图...................................................................................27 4.5.3 均匀化及非均匀化网格下的温度云图...........................................................28