Research On The Marine Turbine Round Tile Bearing Oil-Film Force Excitation Characteristics

Rotor-bearing system is the core component of marine steam turbine; turbine rotor is able to avoid resonance vibration and the critical speed with the reasonable distribution of the critical speeds. However, it is difficult to predict the critical speed of a rotor-bearing system accurately due to the system complexity in practice. The oil-film is the dominant factor to the critical speeds and its distribution. Therefore, it is of great theoretical and practical significance to study the dynamic coefficients of the bearing.Based on the hydrodynamic lubrication theory,the paper introduced the movement of bearing condition and the principle of lubrication. Meanwhile, the refinement is developed to the traditional iterative relationship and iteration termination conditions of the Finite difference method. Calculating accuracy is significantly improved.Measuring and identifying the bearing dynamic coefficients through the method of altering the support stiffness, a rotor-bearing testing rig with the changeable supporting stiffness is designed and built, which is able to identify the bearing dynamic coefficients in different speed and bearing force through adjustment of the supporting stiffness.Besides, the paper compares the theoretical results with the experimental identification value that facilitate the refinement of the theoretical calculation program. Moreover, the comparisons show the relationship between the speeds, the bearing force with the dynamic coefficients. It provides theoretical support for marine turbine design.