简介：AlateralHelmholtzresonatoraddedtoastandingwavetubewithoutflowhasbeenvalidatedasamethodofnoisereductionforcombustionnoiseradiatedfromcombustionchannelofrocketsorturbines.Butinfactthereisaflowwithlowvelocityinthecombustionchannel.ThereforethetheoreticalanalysiscarriedoutisaimedatsoundfieldofstandingwavetubewithflowandwithlateralHelmholtzresonator.Certainlyarelevantmath-physicalmodelshouldfirstbeformulated.Herethreekeyproblemsneedtobesolved:(1)ToformulatethediscontinuityconditionatthejointbetweenthestandingwavetubeandHelmholtzresonatorinthecaseofflow.(2)TodeterminetheacousticimpedanceofHelmholtzresonator,consideringtheeffectsofflow,viscousandmulti_hole.(3)Toformulatethereflectionconditionattheendofthestandingwavetube.SomeformulasforanalysisofthesoundfieldinthetubewithflowandwithlateralHelmholtzresonatorarededuced.Thesetheoreticalworkshavebeenvalidatedbyexperiments.

简介：BasedonthetheoreticalanalysisofastandingwavetubewithflowandlateralHelmholtzresonator,arelevantexperimentalapparatusweresetup,andweresuccessfullyusedtovalidatethetheanalysisabove.Meanwhileanendcorrectionandanequivalentradiuscoefficientcoveredinthetheoreticalanalysiswerealsodeterminedbyexperiments.FurthermoreseveralresultsobtainedfromthetheoreticalanalysisandexperimentswereusedtodiscusstheeffectsofflowontheperformanceofHelmholtzresonatorandthesoundfieldinthestandingwavetube.ItisshownthatusingHelmholtzresonatorforthestandingwavetubewithflowisstillagoodmeasurefornoisereduction,eventhoughtheeffectofnoisereductioncouldbereducedbecauseofflow.