Stability Analysis of a Rigid Rotor Supported on Gas Foil Bearings Under Different Loading Conditions

Gas foil bearings (GFBs) has been considered as an alternative to traditional bearings in turbopumps, turbocompressors, and turbochargers. The popularity of this bearing has motivated the researchers and people from industries to explore its capabilities. In this context, a nonlinear transient analysis of a rigid rotor supported on airfoil bearing under unidirectional constant load and unidirectional periodic load is carried out. The nondimensional form of the Reynolds equation is discretized using Finite Difference Method while the Crank–Nicolson method and Newton–Raphson method are used to obtain the pressure at every time step. Mass parameter, which is a function of the speed of the rotor, has been considered as the parameter of stability. It has been observed that a rotor stable under unidirectional constant load can be unstable under unidirectional periodic load.