Foil bearings are considered to be an excellent fit for a range of high-temperature applications. However, they are susceptible to collapse as a result of thermoelastic instability (TEI). This study introduces a novel approach to enhance passive cooling by adding fins to the surface of the hollow journal cylinder. The effect of enhanced heat transport on the thermoelastic evolution of the bearing surface is thoroughly explored. Furthermore, the critical speed of a foil bearing is derived after taking into account the effect of fins. This affordable method enables the designer to increase the threshold speed of TEI and guard against foil-bearing failure.
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