For nickel-based single crystal superalloy DD6 (AECC Beijing Institute of Aeronautical Materials, Beijing, China) material, a method for predicting creep rupture time was proposed based on a newly defined equivalent stress method. An anisotropic creep model for describing the orientation-dependent creep behavior and lifetime of a nickel-based single crystal superalloy was proposed. The creep subroutine was written based on the proposed nickel-based single crystal creep model. The stability of the model was improved by adjusting the iterative algorithm. The creep calculation results in [001], [011], and [111] loading directions were compared with the experimental results. The accuracy of the calculation results by the nickel-based single crystal creep subroutine was verified. The initial time step and maximum time step of the creep subroutine were studied.

Creep tests were conducted on DZ411 material at 930 °C and 850 °C, and creep curves were recorded and employed in normalization creep model building. A yield function suitable for directional solidification nickel-based materials was proposed in an ascending-order approach. Combined with the normalized creep model and the proposed function, a creep subroutine was compiled to simulate the creep deformation behavior of a turbine blade. The typical boundary conditions of the blade were determined and used for finite element analysis. According to the analysis results, the assessment positions for the actual application of a turbine blade were determined and checked for endurance intensity. The phenomenon of deviation angle between crystal axis and blade height direction in actual casting was further analyzed. Multiple angles and directional deviation angles were simulated for 10,000 h creep deformation. Considering the difficulties and challenges of the complex geometric structures of blades, it is necessary to conduct creep tests of DZ411 material and a simulation analysis of a real blade. Based on the above analysis and discussion, the present work sheds light on finite element analysis and has great potential for structural analyses in the engineering applications of complex high-temperature structures.

The vibration of turbine blades during the operation of jet engines is a serious and complex issue that has garnered significant attention. In practical jet engines, dry friction damping is commonly used to suppress blade vibrations due to its reliability and efficiency. The equivalent damping ratio of dry friction dampers is a crucial metric for evaluating their performance. However, calculating dry friction dampers’ damping ratio for actual structures involves nonlinear vibration calculations, which are challenging and often lack precision. A method combining simulation and experimentation to calculate the equivalent damping ratio of a structure is proposed. In a laboratory setting, the vibration response of turbine blades under centrifugal load and the damping effect of under-platform dampers were analyzed using oil excitation. The research results indicate that this method can effectively calculate the equivalent damping ratio of actual structures. The findings provide robust support for the design of under-platform dampers and the vibration analysis of turbine blades.

The tubed vortex reducer is a new structure of aero-engine, which is widely used in advanced large bypass ratio high performance turbofan engines. It is usually installed between the rear two-stage discs of the high-pressure compressor, and reduces the generation of free vortices by restricting the flow path of the cooling airflow, thereby reducing the pressure loss of the cooling