Modeling of a controllable tilting pad bearing

Develops two models of a controllable tilting pad bearing supporting a rotating shaft. The first is a nonlinear model based on a Reynolds-equation description of the lubricant film. The second is a linear state variable model whose parameters depend on the local bearing stiffness and damping coefficients at a given equilibrium position. The models allow for the bearing pads to be independently moved radially in and out in order to control the motion of the shaft. The linear model is suitable for multivariable feedback control design computations. The nonlinear model provides a more realistic simulation which is used to evaluate the closed loop system dynamic behavior.