ECOFRIENDLY LUBRICANT OILS' PERFORMANCE IN LARGE HYDROELECTRIC THRUST BEARINGS

In this paper the modified Reynold's and energy equations of a hydroelectric thrust bearing were solved simultaneously using a scheme of finite differences. Variations in viscosity across the pad film, as well as the hot oil carryover effect, were taken into account. The pad deformation was computed using ANSYS and a linked finite-element technique. A mesh convergence test verified the convergence of the numerical results. The analyzed lubricants were DTE heavy medium oil and a variety of next generation low tox turbine oils. An additional theoretical and established experimental analysis was used to estimate and compare lubricant toxicity. Unlike in previous studies, this study defines the independent factors which control the selection of a lubricant viz. its hydrodynamic efficiency and toxic content.