毕业论文（设计）_三维圆管流动状况的数值模拟分析.docVIP

毕 业 论 文 学生姓名： 袁洪武 学 号： 学　 院： 土木工程与力学学院 专业年级： 2008工程力学 题 目： 三维圆管流动状况的数值模拟分析 指导教师： 蒋光彪 副教授 评阅教师： 余 敏 讲 师 2012年　5 月 摘 要 在工程和生活中，圆管内的流动是最常见也是最简单的一种流动，圆管流动有层流和紊流两种流动状况。雷诺数是判别流体流动状态的准则数。本文用Fluent软件来模拟研究三维圆管的层流和紊流流动状况，主要对流速分布和压强分布作出分析。 首先在Gambit里建立物理模型，分别建立直圆管与90度弯圆管的物理模型，并划分网格。选用液体流动的质量守恒方程、动量守恒方程、能量守恒方程以及方程，分别对层流和紊流采用不同的3种入口流速来对三维圆管内部流体进行模拟分析，并在FLUENT软件中以直观的方式表示出了层流和紊流各种不同速度在圆管中的流动状况，分析讨论其不同流速下的规律、特点。并通过几种理论方式计算验证所得到的数值模拟结果的准确性。 结果证明所得到的数值模拟结果与圆管层流、紊流的理论数据相符合。 关键词 FLUENT；光滑圆管；湍流；层流；雷诺数；数值模拟 Title The numerical simulation and analysis of the flow in the 3D round tube Abstract: In engineering and life, circular pipe flow is the most common and the simplest flow, and it contains two flow conditions-aminar and turbulent. Reynolds number is used to distinguish the fluid state criterion. This paper is to simulate study of three-dimensional pipe laminar and turbulent flow by Fluent software, which mainly makes analysis on the velocity distribution and the pressure distribution . First, establish physical model in the Gambit, respectively, set straight circular pipe and 90 degree bend pipe physical model, and then, mesh. Selecting liquid flow equation of mass conservation, momentum conservation equation and energy conservation equation of laminar flow and turbulent flow, we can, respectively, use 3 different entrance velocity to make simulation analysis of 3D pipe internal fluid. In Fluent software , this paper expresses the different velocity of laminar and turbulent flow in pipe flow condition in an intuitive way, discussing pattern and characteristics under different flow, and verifies the accuracy of the numerical results through several theoretical method. Results show that the numerical results are Conformed to the theory datas of Laminar and turbulent flow . Keywords: Fluent; Smooth pipe; Turbulent flow; Lamin