DETERMINATION OF CRITICAL FREQUENCIES OF ROTARY SYSTEMS WITH CONICAL-CYLINDRICAL SLIDING BEARINGS BASED ON THE ANALYSIS OF DYNAMIC COEFFICIENTS

The study objective. The research is aimed at developing a technique for accurately predicting critical frequencies and assessing the stability of high-speed rotory systems supported by conical-cylindrical sliding bearings (CCSB), a promising technical solution for combined radial and axial loads. The key goal is to establish the relationship between the geometric and operational parameters of the bearing and the dynamic characteristics of the system. Study results. Based on the hydrodynamic model, an approach to determining the coefficients of stiffness and damping of the lubricating layer in CCSB is proposed and implemented. The obtained dynamic coefficients were integrated into the rotor model to perform modal analysis and stability analysis according to Routh-Hurwitz criterion. The calculation results made it possible to quantify the dependence of dynamic coefficients on operational parameters, identify the first critical frequencies, and construct diagrams of system stability. Conclusions. Based on the results of the study, recommendations are given on the choice of an optimal design and safe operation of rotors in turbomachines, taking into account the main requirements for the range of critical frequencies, the level of stability and the combined load capacity of CCSB.