| 1. | Unsteady flow analysis of vibrating cascade under flow structure coupled condition
气固耦合振动叶栅非定常流动分析研究 |
| 2. | First , a 2 - d unsteady viscous flow in a vibrating cascade is investigated under flow - structure uncoupled conditions
本文首先研究气固非耦合条件下的振动叶栅内二维非定常粘性流动。 |
| 3. | By using a finite volume method to solve the navier - stokes equations , two - dimensional vibrating cascade flow was computed
采用有限体(面)积法求解navier - stokes方程，完成了二维振动叶栅流动数值模拟。 |
| 4. | The numerical flutter analysis system was formed by the three - dimensional numerical simulation of the vibrating cascade flow combined with the structural dynamics analysis of vibrating blade
将振动叶栅三维流动数值模拟与振动叶片结构动力学分析相结合，建立了叶片颤振数值分析系统。 |
| 5. | There were some intensively nonlinear features in the vibrating cascade flow . the frequency of the separated vortex ' s propagation was not equal to the vibrating frequency of the blade
二维分析中发现振动叶栅非定常粘性流动具有较强的非线性特征，振动诱发的分离涡传播频率与叶片的振动频率不一致。 |
| 6. | High - resolution nnd scheme and fully implicit dual - time stepping method were adopted in the three - dimensional vibrating cascade flow calculation . thus , the correct simulation of the shock in transonic flow and the efficiency of calculation were both taken into consideration
在三维振动叶栅流动数值模拟中，采用高分辨率tvd类型的格式和全隐式双时间方法，保证了对流动的正确模拟，准确地捕捉了跨音流动中的激波，其计算效率非常高。 |
| 7. | The flows in the case of different reduced frequencies are computed respectively for two blade profiles . by comparing the time curves of relative parameters in oscillating cascades and the flow field contours under different conditions , it is indicated that the reduced frequency is an important factor to determine whether the blade flutter happens or not
针对两种叶型分别计算了不同折合频率下的流场，通过比较振动叶栅相关参数随时间变化的曲线及流场云图，表明折合频率是决定叶片颤振与否的重要因素。 |
| 8. | In the end , the situations of work done by aerodynamic forces on blade surfaces when flow - structure is coupled and is n ' t coupled under the same conditions are compared , the result indicates that the work done by aerodynamic forces after the coupling restraint is unloaded has a distinct change
本文最后比较了相同条件下气固耦合与非耦合时叶表气动力的做功情况，其结果表明解除耦合约束后气动力做功有显著变化，为深入研究振动叶栅流场，必须考虑叶片结构动力因素。 |
| 9. | The navier - stokes equation is discretized in the moving - grid system . by adopting the explicit four - stage runge - kutta jameson finite volume scheme , and under the sustainment of acceleration algorithms such as dual - time stepping method , the multi - grid strategy and implicit smoothing of the residuals , a two dimensional unsteady viscous flow in vibrating cascades is simulated
本文在运动网格体系中离散n - s方程，应用runge - kutta四步显式的jameson有限体积格式，并在双时间方法、多重网格法及残差光顺等加速算法的支持下，计算了二维振动叶栅非定常粘性流场。 |
