Research On Oil Film Characteristics And Stability In Process Of Turbocharger Floating Ring Bearing Design

With the advancement of technology, Turbocharging technology has been widely used inautomotive, marine and aviation. Being one of the key parts of turbocharger, floating ring bearinghas been widely applied in all kinds of precise instruments, high-speed, super-speedrotating machineries and has attracted a great attention by the communities of academiaand enterprises both at home and abroad.Given having not formed the guiding design specifications, as well as the in-depth researchreports on key technology in the design process of turbocharger floating ring bearing, this papermainly focused on the oil film pressure, dynamic characteristics, bearing-rotor system stability issuesof floating ring bearing, based on the study of design process of floating ring bearing.This paper select floating ring bearing as the object of study, mainly analyzes andcalculates the floating ring bearing oil film pressure, dynamic characteristics andbearing-rotor system stability, as well as gives the relevant examples.Firstly, This paper briefly describes the design process, material selecting principle,lubricants selecting principle, and checking principle of floating ring bearing. Thengives the Reynolds assumptions of inner and outer film the floating ring bearing and its’derivation process, Based on the sliding bearing hydrodynamic lubrication theory.Secondly, deduces the stiffness and damping coefficient of floating ring bearing,and compiles corresponding finite element program for inner and outer oil film pressureand dynamic characteristic parameters at different speeds and at different eccentricity,then, draws the corresponding relationship graph.Lastly, deduces the equivalent stiffness and equivalent damping expression offloating ring–rotor-bearing system under the linear condition for the first time, andanalyzes floating ring bearing stability with the Routh-Hurwitz criterion and unstableangular velocity; thus, laid theoretical basis for the floating ring bearing design.