000003840 001__ 3840
000003840 005__ 20141118153345.0
000003840 04107 $$acze
000003840 046__ $$k2008-05-12
000003840 100__ $$aZapoměl, J.
000003840 24500 $$aPROCEDURE FOR INVESTIGATION OF THE EQUILIBRIUM POSITION STABILITY AND FOR THE NONLINEAR RESPOSE OF A ROTOR SUPPORTED BY FLUID FILM BEARINGS AND HAVING A DISC SUBMERGED IN INVISCOUS, INWETTABLE LIQUID

000003840 24630 $$n14$$pEngineering Mechanics 2008
000003840 260__ $$bInstitute of Thermomechanics AS CR, v.v.i., Brno
000003840 506__ $$arestricted
000003840 520__ $$2eng$$aLateral vibration of rotors is significantly influenced by their supports and by their interaction with the medium in the ambient space. If the disc of the rotor is submerged in a liquid and if it vibrates, the pressure field is induced and the liquid acts by a force on the wall of the disc. It is assumed that the disc performs oscillations only with small amplitudes and it enables to describe the produced pressure field by a Laplace's equation and by the relation for the boundary conditions. The liquid is inwettable and it means that it does not lean to the disc surface and therefore no tangential forces acting on the disc are produced. The resulting force is obtained by integration of the pressure distribution around the circumference and along the height of the submerged part of the disc. Its components are proportional to the disc accelerations and it implies that the negatively taken coefficients of proportionality can be considered as additional masses. As the bearing gap is very narrow, the pressure field in the oil film can be described by a Reynolds' equation. In the areas of a vapour cavitation the pressure is considered to be constant. Components of the bearing forces are obtained by integration of the pressure distribution in the oil layer around the circumference and along the length of the bearing. Lateral vibration of such rotor systems is governed by a nonlinear equation of motion. In the neighbourhood of the equilibrium position it can be linearized and this enables to judge its stability utilizing the natural frequencies of the rotor system. For solution of the equation of motion including the transient component a modified Newmark method has been chosen.

000003840 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000003840 653__ $$a

000003840 7112_ $$aEngineering Mechanics 2008$$cSvratka (CZ)$$d2008-05-12 / 2008-05-15$$gEM2008
000003840 720__ $$aZapoměl, J.
000003840 8560_ $$ffischerc@itam.cas.cz
000003840 8564_ $$s677781$$uhttp://invenio.itam.cas.cz/record/3840/files/Zapomel_FT.pdf$$y
             Original version of the author's contribution as presented on CD, , page 1212.
            
000003840 962__ $$r3717
000003840 980__ $$aPAPER