Optimizing energy dissipation in gas foil bearings to eliminate bifurcations of limit cycles in unbalanced rotor systems

Abstract High-speed rotor systems mounted on gas foil bearings present bifurcations which change the quality of stability, and may compromise operability rotating systems, or increase noise level when amplitude specific harmonics drastically increases. The paper identifies dissipating work in film to be source self-excited motions driving whirling close bearing’s surface. energy flow among components a bearing system with unbalance is evaluated for various design sets bump properties, stiffness magnitude. presents methodology retain at positive values during periodic limit cycle caused by unbalance. An optimization technique embedded pseudo-arc length continuation cycles, those (when exist) utilizing an orthogonal collocation method. scheme considers damping as variables do not appear certain speed range. It found that secondary Hopf (Neimark–Sacker) bifurcations, trigger large motions, exist unbalanced rotors properties follow pattern. Period-doubling (flip) are possible occur, without high response amplitude. Different magnitude investigated efficiency method eliminate bifurcations. pattern allows real time, shift operation, eliminating allowing operation higher margins. Compliant enhance stability system.