简介：Theflowstructuresinaseparatedshearlayeractuatedbyasyntheticjetactuatorwerestudiedusingexperimentalmethods.Whenforcedatafrequencymuchlowerthanthenaturalsheddingfrequency(fH/U=0.042orfX_r/U=0.24),theverticalflappingmotionoftheshearlayerdownstreamoftheseparationpointbecameprominent.Thesizeofthepeakinthepressurespectraattheforcingfrequency(St_A=f_AH/U)measuredneartheseparationpoint(x/H=1)increasedlinearlywiththeforcingamplitude(u′/U)suggestingalinearresponseofthepressurefluctuationstotheforcingbythesyntheticjet.ThelinearresponsedidnotholdforthepressurefluctuationsawayfromthejetexitasthemagnitudeofthepeakforSt_Ameasuredatx/H=3soonsaturatedwhentheforcingamplitudebecamelargerthan0.3.