简介：Withtheadvantagesoftransmittingenergyfrommultipledirectionstoonedirectionandtransformingvibrationfromonesourcetomultipledirections,thetwo-dimensionalvibrationdirectionconverterhasimportantapplicationsinpowerultrasonictechnology.However,forthecomplexityofusingthewaveequationtodesignandanalysisthetwo-dimensionalvibrationdirectionconverter,aconciseequivalentcircuitfortheconverterisinvestigated.Byintroducingthetwo-dimensionalmechanicalcouplingcoefficientandthelongitudinalforcetransformcoef-ficient,andusingtheelectromechanicalanalogyprinciple,theequivalentcircuitandresonancefrequencyequationofthetwo-dimensionalvibrationdirectionconvertervibratinginanti-phaseandin-phasetwo-dimensionalcoupledvibrationarededuced.Theresonancefrequenciesofthevibrationdirectionconvertersoftwodifferentmaterialsarecalculatedbyusingtheproposedfrequencyequation,whichareinagreementwiththeresultsfromthefiniteelementmethodandtheexperimentaltest.Itprovidesaconcisemethodforthedesignandapplicationsofsuchultrasonicvibrationsystem.

简介：Thefinite-dmerencetime-domam（FDTD）methodisproposedforanalyzingthesurfaceacousticwave（SAW）propagationintwo-dimensional（2D）piezoelectricphononiccrystals（PCs）atradiofrequency（RF）,andalsoexperimentsareestabhshedtodemonstrateitsanalysisresultofthePCs’bandgaps.TheFDTDmethodtakesthepiezoelectriceffectofPCsintoaccount,inwhichperiodicboundaryconditionsareusedtodecreasememory/timeconsumptionandtheperfectlymatchedlayerboundaryconditionsareadoptedastheSAWabsorberstoattenuateartificialreflections.TwoSAWdelaylinesareestabhshedwith/withoutpiezoelectricPCslocatedbetweeninterdigitaltransducers.Byremovingseveralechoeswithwindowgatingfunctionintimedomain,delaylinestransmissionfunctionisachieved.ThePCs’transmissionfunctionsandbandgapsareobtainedbycomparingtheminthesetwodelaylines.WhenAluminum/128°YX-LiNbO3isadoptedasscatterandsubstratematerial,thePCs’bandgapiscalculatedbythisFDTDmethodandCOMSOLrespectively.ResultsshowthatcomputationalresultsofFDTDagreewellwithexperimentalresultsandarebetterthanthatofCOMSOL.

简介：双交换边界元素方法(DRBEM)被使用与三维的潜在的流动预言管和silencers的声学的特征，并且基本原则和建议方法的数字过程是到常规边界元素方法(CBEM)的introduced.Compared，DRBEM在声学的管理方程考虑流动马赫数字的第二个顺序术语，它对有更高的马赫数字的状况合适亚声的flow.The四杆的parame