Effect of Thermal Distortion on Performance of Hybrid Journal Bearing

This paper presents static and dynamic performance characteristics for a hole-entry hybrid journal bearing system by applying theoretical investigation. The oil-film thickness was affected by the bush deformation. Temperature change and deformation because of oil-film pressure are the main contributors toward the total deformation in bearing bush. This work intends to investigate the relative influence of each of these components on performance characteristics. The journal temperature was calculated by use of oil-film temperature. Finite element method was applied for solving the governing equations by using appropriate iterative technique and for computation of journal temperature. Study was performed on symmetric and asymmetric hole-entry hybrid journal bearing configurations to evaluate the thermoelastohydrostatic performance for constant flow valve flow restrictor. Performance of the hole-entry hybrid journal bearing shows that the selection of coefficient of thermal deformation plays vital role in controlling the variation in key bearing design parameters as compared to change in temperature of the lubricating oil and bush.