流体・構造片方向連成解析のためのFrontISTRカスタマイズとそのタービンブレード問題への応用

抄録

These days, with the increasing demand for renewable energy, steam turbines used in power plants needs to be operated under wide range of steam condition. The last stage blade of LP (Low Pressure) turbine is designed very long and thin to reduce kinetic energy of the exhausted steam, which often adopts structural limit design. To operate LP turbine safely, reversed flow phenomenon under very low volume flow condition need to be considered. With similarity to the phenomenon in axial compressors, we call this reversed flow as “stall cell” in this paper. One-way coupled Fluid-Structure Interaction analysis was conducted with open-source parallel Finite Element Method structural analysis software FrontISTR, which was customized for applying fluid traction on the surface of turbine blades. The result of calculation was consistent with a model experiment in terms of peak frequency excited by stall cell and its overall vibration stress.