非均匀来流条件下偏心涡轮转子的气流激振力和动力特性

转子的偏心与非均匀来流都会使得涡轮内的流动变得周向非均匀,从而产生气流激振力作用于转子。以轴流涡轮为研究对象,对双耦合激励盘模型的叶片尺度子模型进行了简化,利用简化模型分析了转子偏心和非均匀来流所产生的气流激振力。将偏心转子的分析结果与试验结果进行了比较,验证了简化模型的正确性。在此基础上就非均匀来流对偏心涡轮转子动力特性的影响进行了分析,讨论了受迫振动的位移响应和自激振动的稳定性条件。结果表明,在一定条件下,非均匀的来流也会对转子系统的运动稳定性造成影响。

Aerodynamic excited forces and dynamic characteristics of eccentric turbine rotor in non-uniform inlet flow conditions

The centroid offset of turbine rotor and the non-uniform inlet flow can make the flow non-axisymmetric, and then an aerodynamic excited force acting on the rotor will occur. An analytic study is presented by simplifying the radius scale sub-model of two coupled actuator disk model used to study on axial turbine. With this method, the aerodynamic forces due to rotor eccentricity and non-uniform inlet flow are predicted. The predicted results of the eccentric rotor are compared with the experimental data, so the simplified method is verified. Meanwhile, the influences of non-uniform inlet flow and rotor eccentricity on the dynamic characteristic are analyzed, and the response of forced vibration and the stability of self-excited vibration are discussed. The results show that, under certain conditions, non-uniform inlet flow can also affect the kinetic stability of the rotor system.