基于CFD技术的管内流动精细仿真方法

An Accurate Simulation Method of Pipe Flow Based on CFD

利用数值仿真方法模拟管内流动具有适应性好、高效方便的优势.充分考虑到管道壁面对管内流动的作用,引入湍流双层流动模型分别对近壁面和管道中心流场进行求解.采用增强壁面处理方法描述壁面对流场参数的影响关系,选取了合理的边界条件和计算区域以消除管道物理模型对流场边界的反作用,基于CFD技术发展了一种可对管内流动进行精细模拟的数值方法.通过对典型直管和三维细长管道的计算结果的分析,表明所建立的数值方法准确模拟了管道入口处流场的发展过程,通过对数值计算结果与理论计算结果的对比分析,表明所建立的数值方法正确、模拟精度较高.

Computational fluid dynamics（CFD）is considered as a robust,efficient and convenient method to solve the internal flow field of pipe.In order to simulate the impacts of presence of pipe walls,the two-layer turbulent model was employed to define the near-wall region and fully-turbulent region＇s flow respectively.The enhanced wall treatment was used to calculate flow field in near-wall region.Proper boundary conditions and simulation region were selected to prevent pipe＇s structure affecting the boundary conditions reversely,also to achieve more accurate simulation solutions.Used these models,an accurate computational method of pipe flow was built based on CFD technique.The internal flow field of two kinds of typical pipes,straight pipe and 3D curving pipe,were solved to use the built computational method.The flow field is quantitatively described well,such as the developing process when the fluid just flows into pipe.Parts of results can be attained numerically as well as analytically were compared,and the validity and accuracy of the computational method are proved.