偏心圆管中非牛顿流体热环境的数值计算研究
关键词 非牛顿流体 非结构化网格 有限体积法 偏心圆环管 充分发展层流
毕业设计说明书外文摘要
Title Numerical calculation of non-Newtonian fluid thermal environment in
the eccentric tubes
Abstract
As various non-Newtonian fluids being applied to everyday life，many scholars start to study them. In this paper, first we used unstructured mesh to pide the two dimensional section of eccentric annular tube by grid, dispersed the diffusion terms of the diffusion equation through finite volume method, and dispersed the apparent viscosity through cell-based method. Then, by calculating the velocity field of steady laminar flow in three different shapes of open channel, we compared the numerical solutions with analytic solutions and testified our program’s applicability. Also, by introducing the power law model, we compared shear thinning flow and the shear thickening flow and had drew conclusions through calculating their flow (velocity field) and heat transfer (temperature field) in three different cases. Finally, we compared Nusselt number (Nu) from references with the isothermal friction coefficient ( ), and proved our conclusions correct.
Keywords Non-Newtonian fluid, Unstructured mesh, finite volume method, eccentric annular tube, fully developed laminar flow
目 次
1 绪论 1
1.1 研究背景 1
1.2 本课题研究意义 2
1.3 国内外研究现状 3
1.4 本文研究内容 5
2 牛顿流体充分发展层流的控制方程与离散 6
2.1 计算域的介绍 6
2.2 控制方程的离散 7
2.2.1 非结构化网格的生成 7
2.2.2 扩散项的离散 8
2.2.3表观粘性系数的离散 11
2.3 初始条件与边界条件的介绍 13
2.3.1初始条件 13
2.3.2边界条件 13
2.4 计算程序结构的介绍 14
3 程序适用性的验证 16
3.1 无量纲参数的介绍 16
3.2 程序的验证 17
3.3 本章小结 22
4 偏心圆环关非牛顿流体流动与传热的数值计算 22
4.1 有关非牛顿流体流动的问题描述 22
4.1.1 剪切稀化流的流动 24
4.1.2 剪切稠化流的流动 30
4.1.3 小结 34
4.2 有关非牛顿流体传热的问题描述 34
4.2.1 剪切稀化流的传热 36
4.2.2 剪切稠化流的传热 40
4.2.3 小结 44