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This work details the heat generation analysis of a turbine aero-engine main-shaft bearing using the computer program Advanced Dynamics Of Rolling Elements (ADORE). The empirical models used for traction and churning heat generation are detailed. The predictions of ADORE are shown to demonstrate the differing contributions of traction and churning to total heat generation at different load/speed regimes. These results are then compared with experimental results. In addition, the results of ADORE are also compared with results from the well-known bearing analysis program SHABERTH (Shaft Bearing Thermal Analysis). The comparisons showed good agreement between ADORE and the experimental results for loads between 13.35 and 53.40 kN and speeds between 1.8 and 2.2 MDN. The results also showed under prediction of heat generation by SHABERTH in this regime. Limitations of both programs were identified and speculated to include limitations in the empirical models due to the lack of available experimental traction data at high speeds/loads. Finally, recommendations for future research are provided which will likely provide significant improvements in the ability to predict bearing heat generation in turbine aero-engine applications.

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Wright Patterson AFB OH 45433133 mm bore ball bearings with metal rolling elements were tested at the following conditions: speeds from 1.5 × 10 6 to 2.6 × 10 6 DN; thrust loads from 13,350 to 53,400 N; oil delivery temperatures from 66 to 121 • C; and oil flow rates from 7.3 to 11.4 L/min. The resulting bearing outer race temperature, oil exit temperature, and power loss determined from the shaft torque and power loss determined from the oil temperature rise are reported. Experimental power loss values are compared to the analytical results obtained with the computer code SHABERTH.The experimental data are also fitted to an empirical equation to predict the total bearing power loss. The results indicate that bearing operating temperature is a challenge for next-generation engines, primarily driven by limits of polyolester lubricants used in gas turbine engines. The results also indicate that the computer code SHABERTH underpredicts the bearing lower loss at high load conditions. A new empirical model was able to reasonably predict the bearing power loss over the conditions studied.