Stress Field Simulation of Single Crystal Turbine Blade During Unidirectional Solidification

Abstract

According to the bottle neck problem about low size precision and large wall thickness deviation of the single crystal turbine blade, considering the inaccuracy factors of boundary conditions during unidirectional solidification process, the contact element method was used to study the interaction between the blade and the shuttering. Meanwhile, the practice temperature field data,the finite element method with the coupled stress field and temperature field, were used to simulate the unidirectional solidification of the single crystal turbine blade. Based on the analysis result, the stress distributing and blade deformation were qualitatively discussed. The result indicates that the max-residual stress presents at the root air-inlets, and the max-residual stress of root air-inlets is 28.4% higher than that of blade-body. The dynamic change of the temperature and the stress can basically been reflected by the coupled temperature/stress method. It can provide references for modifying process for reducing the cast residual stress, improving dimensional accuracy and dimensional stability in the unidirectional solidification process.

Keywords

• single crystal hollow turbine blade
• unidirectional solidification
• coupled temperature/stress
• stress field simulation