简介:Anewmodelforasmartshellofrevolutiontreatedwithactiveconstrainedlayerdamping(ACLD)isdeveloped,andthedampingefectsoftheACLDtreatmentarediscussed.Themotionandelectricanalyticalformulationofthepiezoelectricconstrainedlayerarepresentedfirst.Basedontheauthors’recentresearchonshellsofrevolutiontreatedwithpassiveconstrainedlayerdamping(PCLD),theintegratedfirst-orderdiferentialmatrixequationofashellofrevolutionpartiallytreatedwithringACLDblocksisderivedinthefrequencydomain.Byvirtueoftheextendedhomogeneouscapacityprecisionintegrationtechnology,astableandsimplenumericalmethodisfurtherproposedtosolvetheaboveequation.Then,thevibrationresponsesofanACLDshellofrevolutionaremeasuredbyusingthepresentmodelandmethod.TheresultsshowthatthecontrolperformanceoftheACLDtreatmentiscomplicatedandfrequency-dependent.Inacertainfrequencyrange,theACLDtreatmentcanachievebetterdampingcharacteristicscomparedwiththeconventionalPCLDtreatment.
简介:Athird-ordercorrectionwasrecentlysuggestedtoimprovetheaccuracyofthehalf-powerbandwidthmethodinestimatingthedampingofsingleDOFsystems.Thispaperanalyzestheaccuracyofthehalf-powerbandwidthmethodwiththethird-ordercorrectionindampingestimationformulti-DOFlinearsystems.Dampingratiosinatwo-DOFlinearsystemareestimatedusingitsdisplacementandaccelerationfrequencyresponsecurves,respectively.Awiderangeofimportantparametersthatcharacterizetheshapeoftheseresponsecurvesaretakenintoaccount.Resultsshowthatthethird-ordercorrectionmaygreatlyimprovetheaccuracyofthehalf-powerbandwidthmethodinestimatingdampinginatwo-DOFsystem.Inspiteofthis,thehalf-powerbandwidthmethodmaysignificantlyoverestimatethedampingratiosoftwo-DOFsystemsinsomecases.