Development of mathematical models, numerical methods, and software tools for analyzing the durability of radial turbomachinery with parameter mismatching

This study presents mathematical models and numerical-analytical methods for analysing static stresses, free/forced vibrations, and the durability of radial turbomachinery used in power and transportation systems. The research incorporates deliberate disturbances in geometric, mass, and mechanical parameters to evaluate their effects. The finite element method is used as the primary analytical tool, supported by the theories of elasticity and vibration, the mechanics of deformable solids, and gas dynamics. The methodology employs matrix computations and algebraic equation systems to predict the service life characteristics of turbomachine rotors. Custom software interfaces compatible with ANSYS commercial software were developed. Computational studies demonstrated the influence of deliberate parameter mismatches on dynamic loads and durability in both prototype and industrial compressors/turbines. For a radial air handling unit manufactured by Schiele AG (Germany), parameter variations resulted in the alteration of rotor service life characteristics by –10.76% to +14.84%. The numerical analysis tools were implemented in 2024 at the Irkutsk Research and Design Institute of Chemical and Petrochemical Engineering (Russia). The efficiency of the method for durability prediction and strength optimisation during rotor design, fine-tuning, or residual life extension was confirmed by computational experiments. This approach provides a practical tool for further research on the influence of blade parameter mismatches on service life characteristics in axial and radial turbomachines.

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