| When efficiency and rotate speed of Micro-turbine-engine get more and more high, traditional ball/roller bearing is not available, but air bearing is possible to be a good technique to deal with this difficulty. So miniature static pressure journal air bearings used in Micro-turbine engine suitably is studied in this paper.Firstly, the sizes of air journal bearing are fixed on through theory calculation. Then based on these sizes, a test-bed is designed and manufactured. Meanwhile, the sensors and the high speed electromotor are prepared.For the veracity of measuring displacement, the sensors are calibrated; calibrated coefficient and the range of errors are given out.Without the drive of high speed electromotor, many experiments are done to study different supply pressure, different load, different length, different orifice, different location of orifices and different clearance of journal air bearing, 6 factors influence on the characters of journal air bearing of diameter of 15 millimeters and clearance of 50 microns. Then the optimal sizes for journal air bearing used in experiment are given out, the length is 17.5 millimeters, the orifice is 0.5 millimeters and the location of orifice is at third of length. In these experiments, the journal air bearings, whose diameter is 15 millimeters, length is 17.5 millimeters, orifice is 0.4 millimeters, location of orifices is at half of length, clearance is 30 microns, can load 2.26 more weight than itself with the eccentricity bellowing 0.35.At the end, because of lack of time, only the lower speed experiments with drive of high speed electromotor are done. The experiments prove that the dynamic effect can be neglected at the lower speed. Meanwhile, the numerical calculations for dynamic journal air bearing prove the experimental results, and the typical air bearings(φ=15mm, L D=1.17, c = 30μm)can load 1.56N weight at the rotate speed of 32,000 r min, and at the rotate speed of 100,000 r min, 8.0N weight can be loaded.
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