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1、風(fēng)扇噪音分析曾群Analysisofmotor-driventhinbladefannoiseZengQunAbstract:Foralongtime,thereisnotamethodtopredictingthenoiselevelofmotor-drivenblade.Inordertosatisfy,wedevelopedamethodforcalculatingthesoundgeneratedwhenarotatingbladeisexcitedbythetorquepulsationofamotor.Thesoundpressurevaluescalculatedbyt
2、henewmethodforarotatingbladewerefoundtocorrespondwellwithexperimentallymeasuredones?i7.65e*017.20e^)1e.7S^O15.S6?4015.42?>01^53^014.08e>013.64O013.10e*012.74?>01230?心14U4.01X£.13.00z7.05e-010iPhaseofvelocityatithnode(rad);qMassdensity(kg/m3);xAngularfrequency(rad/s);ListofsymbolsdsReferencesmal
3、larea(m2);riInstantaneousdistancefromithnodetoP(m);jImaginaryunit;SAreaofsoundradiator(m2);kFreefieldwavenumberofplanewave(1/m);VVelocitydistributionofsoundradiator(m/s);PFieldpoint(m);ViAmplitudeofvelocityatithnode(m/s);pSoundpressurelevel(Pa);.qAngleofsoundradiator(rad);RObservedradius(m);rDi
4、stancefromreferencesmallareads(m);xrAngularvelocityofrotatingradiator(rad/s);1IntroductionAmethodforpredictingtheelectromagneticnoiseofathinbladefandrivenbyanelectricmotorhasbeendeveloped.Electricmotorsareusedasactuatorsinvariouskindsofmachinery.Vibratingmotionsandnoiseinthemachineryarisewhenth
5、eexcitationforcesofelectricmotorsactonelasticpartsofmachinery.Forinstance,anairconditionerhasafanstructureattachedtothemotorshaft.Thethinbladefanvibratesandradiateselectromagneticnoisewhenthetorquepulsationactsontherotatingblades.Anumberofinvestigatorshavestudiedvibrationandnoisecausedbymotors.
6、Hereweproposeanewnoisecalculationmethodforrotatingbladesthatareexcitedbythetorquepulsationofacapacitormoto匚Thecalculationmethodiscomposedoftwomainmodules,oneforanalyzingthevibrationresponseoftheblades,andoneforcalculatingtheelectromagneticnoiseofarotatingblade.Intheanalyzingmodule,thevibrationr
7、esponseofarotatingthinbladeisanalyzedusingbothtorquepulsationandthemeshmodeloftheblade?Tocalculatethemotortorquepulsation,weemployedanequivalentelectriccircuitcorrespondingtothemoto匚Thecalculatedtorquepulsationwasusedtoobtainthev