Dynamical stability of journal-bearing devices through numerical simulation of thermohydrodynamic models

This paper considers the numerical solution of a transient thermo-hydrodynamical model for a journal-bearing device is considered. The hydrodynamical model assumes that both bush and shaft are rigid bodies and it considers dynamical phenomena in the shaft-lubricant film system through a transient two-dimensional Elrod–Adams model. The proposed model also takes into account thermal effects in the lubricant film, bush and shaft. The dynamical model is solved by a combination of different techniques for spatial discretization (including finite element, finite volume and boundary element methods) and the resulting DAE-like system is integrated with implicit schemes.The developed algorithm is then applied to analyze the stability of steady solutions of the thermo-hydrodynamical model. Existing results based on analytical solutions for simplified configurations are revisited in order to extend stability predictions to more general conditions. This analysis allows to elucidate the role of different parameters on stability, including oil supply and thermal transfer conditions in finite width journal-bearing devices.