Static bearing capacity and static stiffness of pressure equalizing groove cross section with the same width and depth are researched in this paper, it can conclude that the trapezoidal section has the maximum static bearing capacity and static stiffness, while air consumption rate of unit load is the lowest. When compound structure annular hydrostatic thrust bearing has had the optimizing parameters, compared with the single structure one, the bearing capacity had a substantial increasing.

A virtual experiment platform for signal analysis and processing based on LabVIEW is developed. Combined with basic principle and method of signal analysis and processing closely six extensible and workable virtual experiment modules are designed. These modules include signal generator, time domain and frequency domain analysis module, band-pass filter, modem, power-spectrum analysis and boundary checkout of sine signal. A simulation and analysis module of shaft orbit is developed on that basis. In the module some shaft orbit shapes corresponding to typical failures of rotors can be simulated, and the amplitude and frequency spectrum of radial displacement of rotor can be analyzed in real time.

In this paper, a nonlinear energy sink (NES) and a giant magnetostrictive-piezoelectric (GMP) energy harvester (NES-GMP) are investigated to suppress the nonlinear aeroelastic responses and to absorb the mechanical energy of an embedded plate interacting with external subsonic airflow. The analytical model of the embedded plate attaching the NES-GMP is established by using the Hamilton’s principle based on the Kirchhoff plate theory and incompressible subsonic aerodynamic model. The natural frequencies of the plate with the NES-GMP and with the NES are analyzed by solving the generalized eigenvalue problems. The global amplitude-frequency responses of the pure plate, the plate with NES, and the plate with NES-GMP are compared to show the vibration suppression effects of the proposed method. Based on the energy analysis, the energy transfer mechanisms of the plate with the NES-GMP are studied. The results reveal that the input energy of the NES-GMP converts into the strain energy by the Terfenol-D layer and then transforms into the electric energy by the piezoelectric layer. Furthermore, numerical simulations also indicate that the maximum harvested energy is obtained when the airflow velocity approaches the critical divergence flow velocity of the plate, and the most effective harvesting installation position is in a specific annular region near the edge of the plate.

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