부산대학교 도서관

This article dials with the refinement of the mathematical and computational models of the oxidizer turbopump rotor considering bearing gaps, axial preloading, compliance of the housing parts and the effect of rotation. The loading scheme consists of four substeps is proposed considering preliminary displacement of the outer cage, axial displacement as a result of the support deformation due to the axial preloading force, radial displacement due to the support deformation, as well as centrifugal forces of inertia caused by rotation of the rotor with an inner cage. Modelling of contacts interactions using ANSYS software is carried out according to the appropriate models of contact behaviour. The contact areas between the rolling elements, inner and outer cases are obtained. The contact angle is determined. Isosurfaces of axial and radial displacements for the bearing supports are built. Nonlinear stiffness of bearing supports is determined as the tangent of the angle of inclination for the curve “radial load – radial displacement”. The proposed approach, which used for designing turbopump units for liquid rocket engines, will allow refining the reliable mathematical and computational models of rotor dynamics for turbopump units and providing appropriate computer simulation of forced oscillations of the rotor systems for given permissible residual imbalances considering nonlinear stiffness characteristics of bearing supports.