Optimum Hydrodynamic Journal Bearing Performance Characteristics in High-Speed and High-Power Gearboxes

Application of hydrodynamic journal bearings such as pressure dam and offset in high-speed and high-power gearboxes face immense challenges to deliver optimum static and dynamic performances under various operating conditions. Stability, efficiency and oil flow are critical to quality (CTQ) requirements for these gearboxes, and hence, optimum design of journal bearings is required to meet all the performance requirements. For example, bearings designed for optimum static performance at full load and full speed conditions could not deliver the stable dynamic performance at no load conditions. In this study, offset and pressure dam geometries are combined into same bearing and analyzed if the combination can deliver the optimum performance characteristics. The governing mathematical models of Reynold’s equation and energy equation include turbulent and adiabatic thermal effects. The analytical study found that combined offset pressure dam bearing delivers optimum performance at all operating conditions.