轴向间隙对动/静相干叶排内部非定常特性的影响

AXIAL SPACING EFFECTS ON UNSTEADY ROTOR/ STATOR INTERACTION FLOW

本文采用文献［３，４］所发展的滑移界面技术，求解了不同轴向间隙时某一透平级内的非定常流场，发现轴向间隙由０．１５２倍栅距变化到０．５３３倍栅距时，监测点速度ｕ的相对振幅由２６．２７％下降为７．９４％；速度ｖ的相对振幅由２１．３４％下降到７．３％。计算结果表明轴向间隙的增大将使动／静叶排间的相互干扰作用减弱，从而使其内部非定常流动特性减小，为设计工作提供了参考依据。

An investigation has been implemented to simulate the effects of axial spacing on the unsteady rotor/stator interaction. In order to calculate the unsteady flow within a turbine stage simultaneously, a developed sliding interface technique is adopted in conjunction with non-orthogonal grids and non-staggered arrangement techniques. An implicit method is employed to deal with the coupling of velocity and pressure. Some incompressible rotor/stator interactions with low Reynolds number have been simulated under different axial spacing. The structure of vortexes occurred between rotor and stator blade rows have been showed in detail. The results show that increased axial spacing between blade rows in an axial turbine stage can decrease the unsteadiness of flow field.