This paper explores the performance of oil-lubricated bump journal bearings employing micro-pockets on top foil surfaces for lightly loaded applications such as vertical rotor-bearing systems of centrifugal oil filters, vertical pumps, vertical shaft sinking machines and helicopter rotors. The influence of the number of pockets and their attributes on the performance behaviours of the bearing has been presented and explored herein. The six pocketed top foil yields the best performance, followed by four, eight and ten pocketed cases. With micro-pocketed top foil, the coefficient of friction is reduced by 7–18% compared to plain foil. Furthermore, pocketed foil provided improved stability of the rotor.
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