Abstract: Power train architectures with low-loss lubricant bearings and low-density materials are disclosed. The gas turbine used in these architectures can include a compressor section, a turbine section, and a combustor section. A generator, coupled to the rotor shaft, is driven by the turbine section. The compressor section, the turbine section, and the generator each include rotating components, at least one of the rotating components in at least one of the compressor section, the turbine section, and the generator including a low-density material. Bearings support the rotor shaft within the compressor section, the turbine section and the generator, wherein at least one of the bearings is a low-loss bearing having a low-loss lubricant.

Abstract: Mechanical drive architectures can include a gas turbine having a compressor section, a turbine section, and a combustor section. A load compressor is driven by the gas turbine. A rotor shaft extends through the gas turbine and the load compressor. At least one of the rotating components in one of the gas turbine and the load compressor includes a low-density material. Bearings support the rotor shaft within the gas turbine and the load compressor, at least one of the bearings being a low-loss lubricant bearing.

Abstract: Power train architectures with low-loss lubricant bearings and low-density materials are disclosed. The gas turbine used in these architectures can include a compressor section, a turbine section, and a combustor section. A generator, coupled to the rotor shaft, is driven by the turbine section. The compressor section, the turbine section, and the generator each include rotating components, at least one of the rotating components in at least one of the compressor section, the turbine section, and the generator including a low-density material. Bearings support the rotor shaft within the compressor section, the turbine section and the generator, wherein at least one of the bearings is a low-loss bearing having a low-loss lubricant.

Abstract: A method for balancing a rotor of a rotatable machine such as a steam turbine-generator unit. A time-dependent equation is formulated for rotor vibration based on a rotordynamic computer model derived from finite element analysis of the machine's rotor vibration due to centrifugal forces caused by adding unbalance weights. The equation is repeatedly solved in the frequency domain as an optimizer program uses iteration to determine the unbalance weights which will cause the vibration of the rotor of the model to duplicate the measured vibration of the rotor of the machine. Then, balance weights are added to the rotor of the machine which are the inverse of the unbalance weights which were added to the rotor of the model.