An analytical model for complete dynamical coefficients of a tilting-pad journal bearing

An analytical model as well as calculation method is presented for the complete dynamic characteristics of tilting-pad journal bearing. Using this model, the global oil-film forces, stiffness and damping coefficients acting on the journal and all pads can be calculated in a highly concise expression. To improve the computational efficiency, a fast algorithm for calculating the oil-film force and Jacobian of the local pad system is proposed and the Newton–Raphson method is used for solving the equilibrium positions of the journal and all pads. Taking a rigid rotor symmetrically supported on two identical five-shoe tilting-pad journal bearing as an example, the complete dynamic characteristics, damping natural frequency and the stability are calculated. Compared with the traditional reduced model, the numerical results show that the dynamic characteristics can be calculated efficiently and succinctly. The stability can also be overestimated by using the reduced model.