低泄漏高寿命刷式封严的数值计算

Numerical Computation of Low Leakage and High Endurance Brush Seal

通过空气动力学计算方法探索新型低泄漏高寿命三层片式刷式封严结构。利用商用计算流体力学软件STAR-CD,用定常可压缩N-S方程对刷封进行三维流动模拟,计算不同压差下的泄漏情况。以泄漏量作为评价指标,确定新型刷式封严结构的密封特性并对其进行改进。计算结果表明:随着进出口压差的增大,泄漏量增大;改进的封严刷环结构泄漏性能优于简单的片式刷封结构;"70度模型"的泄漏性能略好于"75度模型",说明增加层与层间的夹角可以达到减少泄漏量的效果。

A new style of brush seal with low leakage and high endurance was studied in this paper by the method of the aerodynamic computation.The steady compressible N-S equations were solved numerically to simulate the three dimensional flow in the brush seal structure with the aid of the commerical software STAR-CD.The leakages of the brush seal were calculated for serveral pressure differences.The brush seal structure was evaluated according to the computed leakages.The above results showed that:the leakages become larger with the increase of the pressure difference;the leakages of the new brush seal were smaller than that of the old brush seal;the leakages of the seventy-model were slightly smaller than that of the seventy-five-model.This study indicates that the increase of the angle between the brush seal layers can reduce the leakeges.