Performance Analysis of High-Speed Deep/Shallow Recessed Hybrid Bearing

Shuyun Jiang,Lie Wang

doi:10.1155/2013/918767

Abstract

The present paper proposes a theoretical analysis of the performance of deep/shallow recessed hybrid bearing. It is intended that, on the basis of the numerical results drawn from this study, appropriate shallow recess depth and width can be determined for use in the bearing design process. By adopting bulk flow theory, the turbulent Reynolds equation and energy equation are modified and solved numerically including concentrated inertia effects at the recess edge with different depth and width of shallow recess. The results indicate that the load capacity, drag torque increases as the depth of shallow recess is shallower and the width ratio (half angle of deep recess versus half angle of shallow recess) is smaller. In contrast, the flow rate decreases as the depth of shallow recess is shallower and the width ratio is smaller. Nevertheless, the appropriate design of the depth and width of shallow recess might well induce the performance of high-speed deep/shallow recessed hybrid bearing.

Highlights

The hybrid journal bearings provide superior performance characteristics such as minimum friction, large fluid film stiffness, good damping characteristics, and smooth relative motion
An analysis is conducted and solutions are provided for the effects of the depth and width of shallow recess on the performance of the high-speed deep/shallow recessed hybrid bearing
The temperature is found higher at almost all the points along circumferential directions for the shallow recessed bearing and has the maximum peak value; due to the large flow rate the temperature rise of deep recessed bearing changes not obviously and the value of temperature is not beyond 30∘ which showed the advantages of hybrid bearing using the low viscosity fluid under the high-speed condition

Summary

Introduction

The hybrid journal bearings provide superior performance characteristics such as minimum friction, large fluid film stiffness, good damping characteristics, and smooth relative motion. Helene et al [13] presented the theoretical analysis of the pressure pattern in a two-dimensional recess of a hybrid journal bearing They introduced the ratio of the recess depth versus the film thickness. To the best knowledge of authors, a thorough scan of the available literature reveals that there does not exist any comprehensive study related to the performance of the highspeed deep/shallow recessed hybrid bearing with different depth and width of shallow recess considering the turbulent flow regime and inertia effects in thermohydrodynamic lubrication analysis. An analysis is conducted and solutions are provided for the effects of the depth and width of shallow recess on the performance of the high-speed deep/shallow recessed hybrid bearing. By adopting bulk flow theory, the turbulent Reynolds equation and energy equation are modified and solved numerically including concentrated inertia effects at the deep recess edge with different eccentricity ratios

Theoretical Analysis

Result and Discussion

Conclusion

H: Nondimensional film thickness θ: Angular coordinate ω