【英文标准名称】:Environmentaltesting-Guidance-Coldanddryheattests-Coldanddryheattests
【原文标准名称】:环境试验.指南.低温和干热试验
【标准号】:BSEN60068-3-1-1999
【标准状态】:现行
【国别】:英国
【发布日期】:1999-09-15
【实施或试行日期】:1999-09-15
【发布单位】:英国标准学会(GB-BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:环境试验;辐射;气候试验;温度变化;适宜性;电子设备及元件;产品;热学;试验大气环境;污染控制;电子工程;公差(测量);应力;热传递;辐射热传递;温度;温度测量仪表;试验;电气工程;材料;材料试验;测量;表面;干热试验;方块图;气候;环境;对流;电工产品;热传导;温度分布;低温试验;热循环试验;导热性;指导手册;体积;样品;电学;定义;试验室;试验装置
【英文主题词】:Blockdiagrams;Changesoftemperature;Climate;Climatictests;Coldness;Convection;Definition;Definitions;Dry-heattests;Electricalengineering;Electricity;Electronicengineering;Electronicequipmentandcomponents;Electrotechnicalproducts;Emission;Environment;Environmentaltesting;Guidebooks;Heat;Heatconduction;Heattransfer;Materials;Materialstesting;Measurement;Pollutioncontrol;Products;Radiation;Radiativeheattransfer;Specimens;Stress;Suitability;Surfaces;Temperature;Temperaturedistribution;Temperature-measuringinstruments;Testatmospheres;Testchamber;Testing;Testingdevices;Thermalconductivity;Thermal-cyclingtests;Tolerances(measurement);Volume
【摘要】:Environmentaltesting—Part3:Backgroundinformation—Section1:Coldanddryheattests1.Introduction1.1Referenceambientconditions1.2Deviceswithoutheat-dissipation1.3Deviceswithheat-dissipation1.4Ambienttemperature1.5Surfacetemperatures2.Reasonsforthedifferingtestprocedures2.1Mechanismsofheattransfer3.Testchambers3.1General3.2Methodsofachievingtherequiredconditionsinthetestchamber4.Measurements4.1Temperature4.2Airvelocity4.3EmissivitycoefficientAppendixA—EffectsofsizeofchamberonsurfacetemperatureofaspecimenwhennoforcedaircirculationisusedFIGURE1Heatdissipationperunitsurfaceareaofthetestspecimenatwhichthedeviationbetweenthesurfacetemperatureofthespecimeninaverylargechamberandinasmallerchamberreaches5degCAppendixB—Effectofairflowonchamberconditionsandonsurfacetemperaturesoftest-specimensFIGURE2Experimentaldataontheeffectofairflowonsurfacetemperatureofawirewoundresistor—RadialairflowFIGURE3Experimentaldataontheeffectofairflowonsurfacetemperatureofawirewoundresistor—AxialairflowFIGURE4Temperaturedistributiononacylinderwithhomogeneousheat-generationinairflowofvelocities0.5,1and2m·sAPPENDIXC—EffectofspecimenemissivitycoefficientontemperatureriseFIGURE5Comparisonofthetemperatureriseasafunctionofheat-dissipationforthermalwhiteandthermalblackspecimenssubjectedtoanambienttemperatureof70℃inachamberwiththermalblackwalls.(Exper-imentalvalues.)APPENDIXD—EffectofwireterminationdimensionsandmaterialonsurfacetemperatureofacomponentFIGURE6APPENDIXE—HeattransfercalculationsandnomogramsFIGURE7RelationshipbetweenthesurfacetemperatureTsofthespecimenandtheheatdissipatedPperunittimeattheambienttemperatureTsFIGURE8NomogramforevaluationofsurfacetemperaturesofthespecimenTsatdifferentambienttemperaturesTs.Averagespecimendimensionα=0.2m,emissivitycoefficientofthespecimenε2=0.7FIGURE9NomogramforevaluationofsurfacetemperaturesofthespecimenTsatdifferentambienttemperaturesTs.Averagespecimendimensionsα=0.05m,emissivitycoefficientofthespecimenε2=0.7FIGURE10Relationbetweenovertemperatureandemissivitycoefficientε2ofthespecimenAPPENDIXF—ThermalconductivitiesofcommonmaterialsAPPENDIXC—MeasurementoftemperatureAPPENDIXH—MeasurementofairvelocityAPPENDIXJ—MeasurementofemissivitycoefficientFIGURE11Wien'sdisplacementlawFIGURE12Relationbetweenandλ·TAPPENDIXK—Generalblockdiagram,coldanddryheattestsFIGURE13
【中国标准分类号】:A21
【国际标准分类号】:19_040
【页数】:40P;A4
【正文语种】:英语