This PhD project is set out to develop a type of hybrid journal air bearings with reduced reliance on the supply of compressed air for mobile turbomachinery applications. The research work covers hydrostatic and hybrid journal air bearings with non-compliant clearance boundaries. The approach adopted combined numerical analysis based on CFD and experimental verification of the designs.
The research can be divided into three sections. In the
first section, numerical approaches to model hydrostatic
and hybrid journal air bearings with a fixed clearance
boundary were developed based on finite difference method
(FDM) and finite volume method (FVM) respectively. In the
second and third section, theoretical and experimental
studies were performed on hydrostatic and hybrid journal
air bearings. Performance of the bearings was
investigated in non-rotational and rotational conditions.
The analysis on stability and natural frequencies of
rotor bearing system was performed using the linear
bearing model. The unbalance responses of the rotor in the test rig were predicted using non-linear transient analysis and measured experimentally from 50k rpm to 120k rpm in rotor speed. Through the theoretical and experimental investigations of the hybrid journal air bearings, the objectives of the project have been implemented and the aims have been met
