Designing of Low-flow Rate Sliding Bearings for Turbo Machinery Rotors

Elena Fedorovna Parovay and Sergei Viktorinovich Falaleev

Samara State Aerospace University, Russia, 443086, Samara, Moskovskoye Shaussee, 34, Russia.

ABSTRACT: An effectiveness of support units of modern turbo machines, including sliding supports, largely depends on a design technology. Therefore, the aim of this paper is to develop a new design method of perspective hydrodynamic bearings with an elastic suspension of bushings. In this paper, constructions’ peculiarities and an action mechanism are described as well as a design process of low demand sliding bearings. The efficiency of the proposed sliding bearing design was proved with liners counterbored to a radius of a shaft. A hydrodynamic model of a working bearing gap was described. By means of calculations it was found out that the nature of a pressure distribution in the case of the liners counterbored to a radius of a shaft is smoother (the implementation of the “filled” curve) than in the case of an axial bushings’ counterboring that provides a higher working life of these bearings. A methodology for characteristics’ calculating of an elastic suspension of liners is presented. Elastic deformation material MR properties exclude a “flutter phenomenon” of the bearing liner. The results of calculated researches of perspective bearings’ characteristics are presented and the recommendations for the design optimization were given as well as the choice of materials. The mathematical model of the work system “working gap-liner-elastic suspension” was developed, which allows finding an optimal value of material parameters of “metal analogue of rubber” on the basis of calculations’ results of lubricant flow characteristics in a work gap of as well as a size of a bearing, bearing. The combination of analytical methods and sophisticated software was used, such as ANSYS CFX, ANSYS APDL, ICEM CFD, and NX. A newly created SBDC design method, considers especially construction peculiarities and the mechanism of the work of these bearings. The bearing to be created is an effective solution for heavy-loaded rotors that require a dynamic stability and long life bearings. As part of a cast support a sliding bearing of a “dry crankcase” with liners counterbored to a radius of a shaft can serve as an effective substitute for rolling bearings and for sliding bearings of a traditional construction.

KEYWORDS: sliding bearing; a lubricant layer; elastic suspension; design methodology

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