转盘-静盘腔内层流流动的相似分析及其N-S方程数值解

SIMILARITY ANALYSIS AND NUMERICAL SOLUTION OF N-S EQUATIONS FOR LAMINAR FLOW IN A ROTOR-STATOR SYSTEM

对转盘—静盘系统进行的相似分析表明：转盘—静盘腔内层流流场主要受入口流量数、旋转雷诺数、盘腔间隙系数、密封间隙系数和入口孔径比等５个参数影响。采用ＳＩＭＰＬＥ法对转盘—静盘系统层流流场进行了计算。结果表明：盘腔间隙的大小和密封冠对旋转核的存在具有决定性影响，当入口流量数减小或旋转雷诺数增大时，旋转核趋向于生成且转速增大；证明了影响径向速度的主要是惯性力，而影响周向速度的是惯性力和粘性力共同作用。通过数值计算还得到了防止外燃气“入侵”的最小入口流量数。

The similarity analysis for the N S equations and the boundary conditions of a rotor stator system has been completed which shows that the flow field is depedent on five parameters such as inlet flow coefficient,rotational Renolds number,gap ratio,shroud clearance ratio and inlet diameter ratio.The numerical results for the laminar flow field in the system with an axial inflow and a radial outflow have been obtained by the SIMPLE method.It is shown that the gap ratio and the shroud have a great effect on the existence of the rotational core;and the core tends to take form and increase its rotational speed with decreasing the flow coefficient or with increasing the rotational Renolds number.For the closed rotor stator system the results are in good agreement with earlier work done by the other authors.Both the similarity analysis and numerical computation have testified the conclusion that the radial velocity is dominated by inertial terms and the tangential one is dominated by both inertial and viscous terms.The minimum of the flow coefficient required to prevent the ingress of gas into the rotor stator cavity has been calculated,and its linear relation with the rotational Renolds number has been found,which is consistent with the published experimental data very well.