多分支管道若干流动特性研究

Investigation on flow characteristics in manifolds

通过数值计算对多分支管道的若干流动特性进行研究.在拼片式块结构化网格系统下,采用k-ε紊流模型对多分支管道中的流场进行二维计算,发现对于具有相同尺寸、相同几何型式的多分支管道而言,支管距主管入口端的位置越靠前,通过该支管的流量越小.结合计算结果与实验结果认为,流线弯曲程度对流动的影响是产生这种流量分布趋势的原因.在其他条件不变的情况下,支管流量与主管入口流量近似呈线性关系,支管间的流量差随主管入口流量的增大而增大,随支管间距的增大而减小.

A 2-D patched block-structured grid system is generated for study of the flow characteristics in manifolds. By use of the k-ε turbulent model, the 2-D numerical calculation of the flow field in manifolds is performed with the grid system, and it is indicated that, for the manifolds with the same size and geometric shape, the shorter the distance of a branch away from the inlet of the main duct, the smaller the flow rate through the branch. According to the calculated result and experimental data, this flow rate distribution is mainly caused by the influence of the curvature of streamline on the flow field. Without changes of other conditions, the flow rate through branches is of a linear relationship with that at the inlet of the main duct, and the flow rate difference between branches increases along with the increase of the flow rate at the inlet of the main duct and the decrease of the distance between branches.