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Application of fluid-film bearings in rotor machines in many cases could have no alternative due to obvious advantages when compared to roller element bearings. Integration of information technology in mechanical engineering resulting in emergence of a new field of research – mechatronic bearings which allowed tracking condition of the most important parts of a machine and values of various operational parameters. With the development of sensor devices and actuators of different nature, a number of designs increased in the field of mechatronic technology application to bring the functional of a bearing to a qualitatively new level allowing adjustment of rotor’s position relative to a bearing. Investigation is the direction of rotor’s dynamic behavior control in fluid-film bearings is carried out in the following fields: study of the possibility of profile adjustment of a gap between a rotor and a sleeve or a thrust disk of a bearing, e.g. tilting-pad and some foil bearings; study of the possibility of application of lubricants with adjustable parameters such as viscosity or density, e.g. ferromagnetic fluids; and study of hybrid fluid-film bearings, where load capacity forms as combination of hydrodynamic forces in the film and hydrostatic force from the lubricant supplied into a bearing under pressure, where rotor’s position can be adjusted by means of electrohydraulic devises like servovalves. Application of servovalves to control the flow rate through a bearing is the most universal and simple way of rotor’s position control due to relative simplicity of modeling and absence of need to radically change the design of conventional hydrodynamic bearings.
In the present paper numerical simulations of passive (conventional as opposed to mechatronic) and active hybrid thrust fluid-film bearings with a central feeding chamber have been presented, that are parts of a mechatronic rotor-bearing node, functional scheme of which is presented in the figure 1. Numerical model of an active thrust bearing is based on solution of equations of hydrodynamics, rotor dynamics and an additional model of a servovalve. Various types of control have been investigated: P, PI and PID control, and the dynamic behavior of a system has been estimated under various loads, namely static, periodic and impulse. A design of a test rig has been proposed to study passive and active thrust fluid-film bearings aimed at, among other, validation of numerical results of active bearings simulation.