Ps. Keogh et Pg. Morton, THE DYNAMIC NATURE OF ROTOR THERMAL BENDING DUE TO UNSTEADY LUBRICANTSHEARING WITHIN A BEARING, Proceedings - Royal Society. Mathematical and physical sciences, 445(1924), 1994, pp. 273-290
The influence upon the temperature distribution within a hydrodynamica
lly lubricated journal bearing of a time varying journal orbit is cons
idered and the oscillatory source distribution arising as a result of
unsteady shearing of the lubricant is examined with respect to axes wh
ich rotate with the journal, The time dependent thermal bend induced i
n a rotor by such a process has been evaluated and incorporated into a
rotor dynamic model for the assessment of system stability. Technique
s have been developed enabling calculations to be carried out on an id
ealized rotor-bearing configuration and the speed range over which ins
tability occurred was established. The rate of growth of the unstable
vibrations together with the rate and direction of 'spiralling' of the
thermal bend vector were also determined. Features of rotor and beari
ng design having an influence on such thermally induced instability ar
e assessed.