Abstract
A hydroinertia micro-high speed gas bearing to realize high-speed operation of a micro-rotor at 870,000 rpm for a micromachine-gas turbine of the impeller diameter 10mm, has been developed. The diameter of the journal bearing is 4mm. The outer and inner diameters of the thrust bearing are 10mm and 5mm, respectively. Hydroinertia gas bearing is a type of hydrostatic gas bearing with larger bearing gap than usual. The flow in the wider side of the gap becomes supersonic and generate suction forces to pull them back. The loading capacity can be larger than that of usual hydrostatic bearings. The target speed of 870,000 rpm has successfully been achieved by increasing the supply pressure of the thrust bearings, and shortening the bearing length.
