平成13年7月31日(水)

《平成13年7月31日(水)》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、StudyonPass-byNoiseTestingMethodsIncorporatingUrbanDrivingConditionsTestmethodofN2categoryTransmittedbyJAPAN1.IntroductionInJapan,urbanrunningconditionshavebeeninvestigatedbyusingvarioustypesofroadvehicleswithdifferentpowertomassratios,andnewaccelerationnoisetestmeth

2、odshavebeenstudied.Thesestudiesfoundthat,concerningN2categoryvehicles,thenoiselevelsmeasuredbythetestmethodsdidnotcorrespondwellwiththenoiselevelsgeneratedbyurbanrunning1),2).Therefore,fieldmeasurementsconcerningurbanrunningconditionsandtheaccelerationnoisetestaccord

3、ingtotheISOproposalwereperformedbyusing4vehiclesofN2categoryincludingaCNGvehicle.Inthisreport,theseresultsaredescribed.2.RunningconditionsonurbanroadsTherunningconditionswereinvestigatedbyusing4vehicleswithmaximumpayloadfrom2tonsto4tons(grossvehicleweightfrom4tonsto8

4、tons).Table1showsthespecificationsofthetestvehiclesusedinthisinvestigation.VehicleN2-BisaCNGvehicleandtheothersaredieselenginevehicles.Figure1showsthedistributionofthecumulativefrequencyoftheenginespeedswhentheN2categoryvehiclesranontheurbanroads.The95percentilevalue

5、ofthecumulativefrequencyofeachvehicleisbetween0.67Sand0.77S(S:ratedenginespeed),andtheaveragevalueis0.71S.Figure2showstherelationshipsbetweenpowertomassratioandenginespeed,andbetweenpowertomassratioandacceleration.Inthefigure,thedataofallvehiclesincludingthedatarepor

6、tedinthe36thGRBmeetingareindicated.ThebluesquaresindicatethedataoftheN2vehiclesaddedatthistime.TheenginespeedandaccelerationdataoftheN2vehiclesarealmostonthesamecurveasthevehiclesintheothercategories,andthisfactalsocorrespondstotheCNGvehicle.11113.TestmethodofN2categ

7、orybasedontheISOproposalInthisstudy,astherepresentativevaluesofthenoisegeneratedfromrunningvehiclesonurbanroads,themaximumnoiselevelsinthestartandtheaccelerationrunningconditionwereadopted.Thecalculationmethodofthemaximumnoiselevelhasalreadybeenreportedinthe35thGRBme

8、eting.Figure3showstheexampleoftheestimationresultsofthevehiclespeed,theenginespeedandthenoiselevels.Fromtheresults,themaximumnoisel