简介：Anexperimentalmethodispresentedtoanalyzethedynamicstabilityofthegasbearingforsmallcryogenicturbo-expanders.Therotationimbalanceresponseandtheshapeoftherotororbitwereobtainedfordifferentspeedsupto110,000rpm,andthecriticalspeedoftherotor-bearingsystemwasdeterminedbyaBodediagram.AnFFTsignalanalyticalmethodwasappliedtoidentifytheresonancefrequency,andthewaterfallplotwaspresented.Duringthewholeprocessofspeedinguptothedesignedspeedof110,000rpm,therotor-bearingworksstablywithnowhirlinstability,whichisvalidatedinawaterfallplot.Also,thetestedrotor-bearingmodelwasanalyzedtheoretically.Itwasprovedthattheexperimentalresultswerehighlyconsistentwiththoseoftheoreticalcalculations.Thustheexperimentalmethodproposedheretoanalyzethedynamicstabilityofthegasbearingisfeasible.