导叶约化中心位置对涡轮非定常气动计算的影响

The effect of the stator scaling center position on the turbine unsteady aerodynamic computation

中文关键词: 涡轮  非定常计算  导叶  约化中心位置  气动

英文关键词: Turbine  Unsteady Computation  Stator  Scaling Center Position  Aerodynamics

中文摘要:

      针对工程上常用的基于叶片数约化的涡轮非定常计算方法,为了掌握导叶约化中心位置对于涡轮内部流动非定常计算结果的影响规律,对导叶前缘约化、导叶尾缘约化、不约化三个算例进行了非定常计算与对比分析。研究结果表明,导叶前缘约化方式对于涡轮气动性能时均值影响量级在1%以上,而导叶尾缘约化方式的影响不到前者的1/2。两种约化方式均能捕捉到导叶中的主要流动特征,但前缘约化方式导叶吸力面的吸力峰更强,导叶出口的气流角与马赫数更大。前缘约化方式转静之间的势扰动更强,导叶尾迹也更强,导叶尾缘与动叶前缘上的压力波动更强。根据研究结果,从对涡轮性能与流动的影响来看,同导叶前缘约化方式相比,导叶尾缘约化方式非定常计算结果同无约化方式更接近,故若采用导叶约化进行非定常计算,应优先采用导叶尾缘约化方式。

英文摘要:

      For the universally used blade-scaling unsteady computation method for turbine inner flows, in order to manage the effect rule of the stator blade scaling center position on the turbine inner flow unsteady computation results, This paper had conduct unsteady computations and analysis on the three cases including stator blade leading edge scaling (SQY),stator blade trailing edge scaling (SWY) and no scaling (SNO). The research shows that the effect magnitude of SQY on the turbine performance time-averaged values is above 1%, but the SWY is under 1/2 of the former. Both two scaling methods can catch the main flow features in the stator, but for the SQY case, the suction peak on the stator suction side is stronger, and the flow angle and Mach number at the stator outlet are larger. For the SQY case, the potential disturbance and the stator wake are both stronger, and then the pressure fluctuation on the stator trailing area and the rotor leading area is stronger. According to the research results, from the view of the effect on the turbine performance and flow, compared to the stator leading edge scaling method, the computation results of the stator trailing edge scaling method is closer to the no scaling method. Therefore, when an unsteady computation by the stator scaling method is conducted, the stator trailing scaling one is preferential.