【英文标准名称】:StandardTestMethodforCalculationofStagnationEnthalpyfromHeatTransferTheoryandExperimentalMeasurementsofStagnation-PointHeatTransferandPressure
【原文标准名称】:通过临界点传热与压力的热传递理论和实验测量来计算临界热函的标准试验方法
【标准号】:ASTME637-2005
【标准状态】:现行
【国别】:
【发布日期】:2005
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E21.08
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:航空航天运输;焓;热传递;材料;数学计算;测量;压力;航天技术;临界点
【英文主题词】:enthalpydistribution;enthalpyprofile;localenthalpy;stagnationenthalpy
【摘要】:Thepurposeofthistestmethodistoprovideastandardcalculationofthestagnationenthalpyofanaerodynamicsimulationdeviceusingtheheattransfertheoryandmeasuredvaluesofstagnationpointheattransferandpressure.Astagnationenthalpyobtainedbythistestmethodgivesaconsistentsetofdata,alongwithheattransferandstagnationpressureforablationcomputations.1.1Thistestmethodcoversthecalculationfromheattransfertheoryofthestagnationenthalpyfromexperimentalmeasurementsofthestagnation-pointheattransferandstagnationpressure.1.2Advantages1.2.1Avalueofstagnationenthalpycanbeobtainedatthelocationinthestreamwherethemodelistested.Thisvaluegivesaconsistentsetofdata,alongwithheattransferandstagnationpressure,forablationcomputations.1.2.2Thiscomputationofstagnationenthalpydoesnotrequirethemeasurementofanyarcheaterparameters.1.3LimitationsandConsiderationsTherearemanyfactorsthatmaycontributetoanerrorusingthistypeofapproachtocalculatestagnationenthalpy,including:1.3.1TurbulenceTheturbulencegeneratedbyaddingenergytothestreammaycausedeviationfromthelaminarequilibriumheattransfertheory.1.3.2Equilibrium,Nonequilibrium,orFrozenStateofGasThereactionratesandexpansionsmaybesuchthatthegasisfarfromthermodynamicequilibrium.1.3.3NoncatalyticEffectsThesurfacerecombinationratesandthecharacteristicsofthemetalliccalorimetermaygiveaheattransferdeviationfromtheequilibriumtheory.1.3.4FreeElectricCurrentsThearc-heatedgasstreammayhavefreeelectriccurrentsthatwillcontributetomeasuredexperimentalheattransferrates.1.3.5NonuniformPressureProfileAnonuniformpressureprofileintheregionofthestreamatthepointoftheheattransfermeasurementcoulddistortthestagnationpointvelocitygradient.1.3.6MachNumberEffectsThenondimensionalstagnation-pointvelocitygradientisafunctionoftheMachnumber.Inaddition,theMachnumberisafunctionofenthalpyandpressuresuchthataniterativeprocessisnecessary.1.3.7ModelShapeThenondimensionalstagnation-pointvelocitygradientisafunctionofmodelshape.1.3.8RadiationEffectsThehotgasstreammaycontributearadiativecomponenttotheheattransferrate.1.3.9HeatTransferRateMeasurementAnerrormaybemadeintheheattransfermeasurement(seeMethodE469andTestMethodsE422,E457,E459,andE511).1.3.10ContaminationTheelectrodematerialmaybeofalargeenoughpercentageofthemassflowratetocontributetotheheattransferratemeasurement.1.4ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:A54
【国际标准分类号】:
【页数】:16P.;A4
【正文语种】:


Product Code:SAE AMS3217/2
Title:Test Slabs, Acrylonitrile Butadiene (Nbr-L), Low Acrylonitrile, 65-75
Issuing Committee:Ams Ce Elastomers Committee
Scope:This specification covers a standard acrylonitrile butadiene (NBR-L) rubber stock with low acrylonitrile content in the form of molded test slabs.