ASTM E422-2005 用水冷热量计测量热通量的标准试验方法

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【英文标准名称】:StandardTestMethodforMeasuringHeatFluxUsingaWater-CooledCalorimeter
【原文标准名称】:用水冷热量计测量热通量的标准试验方法
【标准号】:ASTME422-2005
【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】:热通量;热量计;航空航天运输;测量技术
【英文主题词】:calorimeter;heatflux;heattransferrate
【摘要】:Thepurposeofthistestmethodistomeasuretheheatfluxtoawater-cooledsurfaceforpurposesofcalibrationofthethermalenvironmentintowhichtestspecimensareplacedforevaluation.Ifthecalorimeterandholdersize,shape,andsurfacefinishareidenticaltothatofthetestspecimen,themeasuredheatfluxtothecalorimeterispresumedtobethesameasthattothesamplersquo;heatedsurface.Themeasuredheatfluxisoneoftheimportantparametersforcorrelatingthebehaviorofmaterials.Thewater-cooledcalorimeterisoneofseveralcalorimeterconceptsusedtomeasureheatflux.Theprimedrawbackisitslongresponsetime,thatis,thetimerequiredtoachievesteady-stateoperation.Tocalculateenergyaddedtothecoolantwater,accuratemeasurementsoftheriseincoolanttemperatureareneeded,allenergylossesshouldbeminimized,andsteady-stateconditionsmustexistbothinthethermalenvironmentandfluidflowofthecalorimeter.Regardlessofthesourceofenergyinputtothewater-cooledcalorimetersurface(radiative,convective,orcombinationsthereof)themeasurementisaveragedoverthesurfaceactiveareaofthecalorimeter.Ifthewater-cooledcalorimeterisusedtomeasureonlyradiativefluxorcombinedconvective-radiativeheat-fluxrates,thenthesurfacereflectivityofthecalorimetershallbemeasuredoverthewavelengthregionofinterest(dependingonthesourceofradiantenergy).Ifnonuniformitiesexistinthegasstream,alargesurfaceareawater-cooledcalorimeterwouldtendtosmoothoraverageanyvariations.Consequently,itisadvisablethatthesizeofthecalorimeterbelimitedtorelativelysmallsurfaceareasandappliedtowheretheheat-fluxisuniform.Wherelargesamplesaretesteditisrecommendedthatanumberofsmallerdiameterwater-cooledcalorimetersbeused(ratherthanonelargeunit).Theseshallbelocatedacrosstheheatedsurfacesuchthataheat-fluxdistributioncanbedescribed.Withthis,amoredetailedheat-fluxmeasurementcanbeappliedtothespecimentestandmoreinformationcanbededucedfromthetest.1.1Thistestmethodcoversthemeasurementofasteadyheatfluxtoagivenwater-cooledsurfacebymeansofasystemenergybalance.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:A42
【国际标准分类号】:17_200_10
【页数】:5P.;A4
【正文语种】: