能量法和时域法在叶片颤振计算中的比较研究

Comparative Study on Energy Method and Time- domain Method for Blade Flutter Predictions

为了对能量法和时域法这两类叶片颤振计算中的代表性方法进行比较研究,分别介绍了基于CFD技术发展的双通道形状修正能量法和CFD/CSD耦合时域法。前者利用傅里叶级数对周向边界流场变量进行修正而相应的系数由内部单元值进行更新。后者通过耦合非定常气动力计算和结构运动方程求解来实现流场和结构场在时域内的推进。对跨声速风扇转子Rotor67进行计算,结果表明两种方法能够给出一致的颤振特性结果,最后结合算例从多方面对它们进行了比较。

A comparative study of two kinds of representative methods for blade flutter predictions energy method and time domain method is presented in this paper.Particularly,two self developed methods were introduced,which are the double passage shape correction (DPSC) method and the computational fluid dynamics/computational structural dynamics (CFD/CSD) coupled time domain method,respectively.For the former one,the main idea was to correct the flow variables at circumferential boundaries through the Fourier series while the corresponding Fourier coefficients were updated from flow variables at interior boundaries.For the latter one,through coupling between the unsteady aerodynamic calculation and the structural dynamic analysis,the flow field and the structural filed were advanced in time accurately and efficiently,and thus the actual vibration response to the structural disturbance could be obtained.By applying these two methods to a transonic fan rotor Rotor67,it was shown that both of them predicted consistent flutter characteristics.Finally,based on the computed results,comprehensive comparisons between these two methods were carried out from several aspects.