A. N. Laktyushin,a O. O. Smilovenko,b and T. V. Laktyushinaa UDC 621.822.573:519.85 A dynamic model of a rotor system with hydrodynamic plain bearings in which account has been taken of the actually existing phenomenon of the circular anisotropy of the rigidity of hydrodynamic plain bearings has been proposed. The operation of the rotor system has been modeled with the use of uniformity distributed sequences and the region of states of the system representing a set of instantaneous positions of the center of the end rotor surface by which the accuracy of its rotation is evaluated has been obtained. aA. V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, 15 P. Brovka Str., Minsk, 20072, Belarus; bInstitute of Mechanics and of the Reliability of Machines, National Academy of Sciences of Belarus, Minsk, Belarus. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 76, No. 5, pp. 148-153, September-October, 2003. Original article submitted February 7, 2003.