Numerical Simulation of Radial Gas Bearings Based on Fluent Moving Grid
This paper focuses on the double-row aperture radial gas bearing.A gas film model of the radial gas hydrostatic bearing is established through the design software Unigraphics,and the computational fluid dynamics software Fluent is then used to simulate and analyze the gas film model.The small perturbation method,which involves loading a simple harmonic excitation on the journal to replace the spindle vibration during the operation,and the dynamic mesh technology assisted with transient calculation methods are utilized to calculate the stiffness and damping coefficients of the hydrostatic bearings.The study investigates the impact of rotational speed,eccentricity,and gas supply pressure on the stiffness of the hydrostatic bearings under various working conditions,providing a theoretical foundation for the research of hydrostatic bearings and related equipment.The simulation method is validated through experiments by comparing the simulation and experimental results,showing an error of less than 5.5%,which demonstrates the reliability of the simulation calculation.The study indicates that stiffness and damping is affected by rotational speed and eccentricity.Within the rotational speed range of 250 r/min to 1250 r/min,higher speeds result in lower damping and higher stiffness.When the eccentricity ranges from 0.1 to 0.4,higher eccentricity results in higher damping and lower stiffness.