Comprehensive Approach for Identification of Nonlinear Stiffness Characteristics of Bearing Supports for the Oxidizer Turbopump of the Liquid Rocket Engine | Journal of Engineering Sciences

Comprehensive Approach for Identification of Nonlinear Stiffness Characteristics of Bearing Supports for the Oxidizer Turbopump of the Liquid Rocket Engine

Author(s): Pavlenko I.1*, Demyanenko M.1, Edl M.2, Simonovskiy V.1, Pitel’ J.3, Pavlenko V.4, Verbovyi A.1

1 Sumy State University, 2 Rymskogo-Korsakova St., Sumy, 40007, Ukraine;
2 University of West Bohemia, 8 Universitni St., 306 14 Pilsen, Czech Republic;
3 Technical University of Košice, 1 Bayerova St., Prešov, 08001, Slovakia;
4 Machine-Building College of Sumy State University, 17 Shevchenka Av., 40022, Sumy, Ukraine

*Corresponding Author’s Address:

Issue: Volume 5; Issue 2 (2018)

Paper received: April 5, 2018
The final version of the paper received: June 25, 2018
Paper accepted online: July 1, 2018

Pavlenko I. Comprehensive approach for identification of nonlinear stiffness characteristics of bearing supports for the oxidizer turbopump of the liquid rocket engine / I. Pavlenko, M. Demyanenko, M. Edl, V. Simonovskiy, J. Pitel’, V. Pavlenko, A. Verbovyi // Journal of Engineering Sciences. – Sumy : Sumy State University, 2018. – Volume 5, Issue 2. – P. D6-D14.

DOI: 10.21272/jes.2018.5(2).d2

Research Area: MECHANICAL ENGINEERING: Dynamics and Strength of Machines

Abstract. 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.

Keywords: compliance of housing, initial clearance, axial preloading, radial load, contact angle, radial stiffness, axial stiffness.


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