The paper deals with the rotor vibration in journal bearings to prepare a model for verifying the rotor vibration active control. The rotor is maintained in equilibrium position by forces generated in oil film. Bearing forces can be modelled as a spring and damper system. The main goal of the simulation study is to verify the model principle and to estimate parameters by comparing simulation results with experimental data, namely the instability of motion. Test stand with rotor supported in two journal bearings was designed for these purposes. The stand will be equipped with four piezoactuators enabling excitation of bearings by practically arbitrary dynamic force. Theoretical analysis of the influence of external excitation on rotor behaviour was carried out. Up to now the study shows that simple kinematic excitation is effective for reducing rotor excursion while passing critical speeds. To suppress self-exciting vibration of the rotor it is necessary to look for more sophisticated solution. and Obsahuje seznam literatury
New type of aerodynamic tilting pad journal bearing was designed and successfully tested in several applications, one of which was power gyroscope support. Bearing design combines advantages of foil bearings, i.e. additional damping achieved by squeezing out gas film and friction of elastic elements on bearing casing surface, with qualities of classical tilting pad bearings, consisting in defined geometry of bearing gap and excellent stability. Theoretical solution of bearing characteristic calculation is shortly described, consisting in numerical solution of gas flow in narrow gap. Some computed data and results of experiments with rotors operated up to 180.000 rpm are presented too. and Obsahuje seznam literatury