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SAE AIR1168/11 Spacecraft Boost and Entry Heat Transfer (STABILIZED Jul 2011)

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Product Code:SAE AIR1168/11
Title:Spacecraft Boost and Entry Heat Transfer (STABILIZED Jul 2011)
Issuing Committee:Ac-9 Aircraft Environmental Systems Committee
Scope:The prediction of vehicle temperatures during ascent through the earth?s atmosphere requires an accurate knowledge of the aerodynamic heating rates occurring at the vehicle surface. Flight parameters required in heating calculations include the local airstream velocity, pressure, and temperature at the boundary layer edge for the vehicle location in question. In addition, thermodynamic and transport air properties are required at these conditions.Both laminar and turbulent boundary layers occur during the boost trajectory. Experience has shown that laminar and turbulent heating are of equivalent importance. Laminar heating predominates in importance in the stagnation areas, but the large afterbody surfaces are most strongly affected by turbulent heating. Once the local flow conditions and corresponding air properties have been obtained, the convective heating rate may be calculated for a particular wall temperature. This assumes that the boundary layer flow regime (that is, turbulent, laminar, or transitory) has also been established, so that a heating theory corresponding to the particular flow conditions may be selected.This section presents theoretical methods for computing boost vehicle surface aerodynamic heating rates. First, procedures are given for computing the local flow distributions around the vehicle. Second, methods are given for computing the convective heating rates, using the flow parameters found previously.
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【英文标准名称】:StandardTestMethodforDeterminingtheCoefficientofSoilandGeosyntheticorGeosyntheticandGeosyntheticFrictionbytheDirectShearMethod
【原文标准名称】:用直接剪力法测定土壤与土工合成物或土工合成物之间摩擦系数的标准试验方法
【标准号】:ASTMD5321-2008
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【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】:D35.01
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:coefficientoffriction;directshear;geosynthetics;performancetest;Coefficientoffriction(COF)--geosynthetics;Directsheartest;Geosynthetics;Interfacesheartesting;Performance--geosynthetics;Sheartesting--geosynthetics;Sheartesting--soil;
【摘要】:Theproceduredescribedinthistestmethodfordeterminationofthecoefficientofsoilandgeosyntheticorgeosyntheticandgeosyntheticfrictionbythedirectshearmethodisintendedasaperformancetesttoprovidetheuserwithasetofdesignvaluesforthetestconditionsexamined.Thetestspecimensandconditions,includingnormalstresses,aregenerallyselectedbytheuser.Thistestmethodmaybeusedforacceptancetestingofcommercialshipmentsofgeosynthetics,butcautionisadvisedasoutlinedbelow.Thecoefficientofsoilandgeosyntheticfrictioncanbeexpressedonlyintermsofthesoilusedintesting(seeNote1andNote2).Thedeterminedvaluemaybeafunctionoftheappliednormalstress,geosyntheticmaterialcharacteristics,soilgradation,soilplasticity,density,moisturecontent,sizeofsample,drainageconditions,displacementrate,magnitudeofdisplacement,andotherparameters.Note18212;Inthecaseofacceptancetestingrequiringtheuseofsoil,theusermustfurnishthesoilsample,soilparameters,anddirectsheartestparameters.Note28212;TestingunderthisstandardshouldbeperformedbylaboratoriesexperiencedinthedirectsheartestingofsoilsandmeetingtherequirementsofPracticeD3740Thistestmethodmeasuresthetotalresistancetoshearbetweenageosyntheticandasupportingmaterial(substratum)orageosyntheticandanoverlyingmaterial(superstratum).Totalslidingresistancemaybeacombinationofsliding,rolling,interlockingofsoilparticlesandgeosyntheticsurfaces,andshearstrainwithinthegeosyntheticspecimen.Shearingresistancemaybedifferentonthetwofacesofageosyntheticandmayvarywithdirectionofshearingrelativetoorientationofthegeosynthetic.Thetestmethoddoesnotdistinguishbetweenindividualmechanisms,whichmaybeafunctionofthesoilused,methodofsoilplacement,normalandshearstressesapplied,rateofhorizontaldisplacement,andotherfactors.Everyeffortshouldbemadetoidentifyandrecordwithasketch,ascloselyasispracticable,theshearedareaandfailuremodeofthespecimen.Careshouldbetaken,includingclosevisualinspectionofthespecimenaftertesting,toensurethatthetestingconditionsarerepresentativeofthosebeinginvestigated.Informationonprecisionbetweenlaboratoriesisincomplete.Incasesofdispute,comparativeteststodeterminewhetherastatisticalbiasexistsbetweenlaboratoriesmaybeadvisable.Thetestmethodproducestestdatathatcanbeusedinthedesignofgeosyntheicapplications,includingbutnotlimitedto:thedesignofgeosynthetic-reinforcedretainingwalls,embankments,andbasecourses;inapplicationsinwhichthegeosyntheticisplacedonaslope;fordeterminationofgeosyntheticoverlaprequirements;orinotherapplicationsinwhichslidingmayoccurbetweensoilandageosyntheticorbetweentwogeosyntheticmaterials.1.1Thistestmethodcoversaprocedurefordeterminingtheshearresistanceofageosyntheticagainstsoil,orageosyntheticagainstanothergeosynthetic,underaconstantrateofdeformation.1.1.1Thetestmethodisintendedtoindicatetheperformanceoftheselectedspecimenbyattemptingtomodelcertainfieldconditions.Resultsobtainedfromthismethodmaybelimitedintheirapplicabilitytothespecificconditionsconsideredinthetesting.1.2Thetestmethodisapplicableforallgeosynthetics.1.3Thetestmethodisnotsuitedforthedevelopmentofexactstress-strainrelationshipsforthetestspecimenduetothenon-uniformdistributionofshearingforcesanddisplacement.1.4ThevaluesstatedinSIunitsaretoberegardedasth......
【中国标准分类号】:P13
【国际标准分类号】:59_080_70
【页数】:7P.;A4
【正文语种】:英语


【英文标准名称】:StandardTestMethodforBondStrengthofMortartoMasonryUnits
【原文标准名称】:砌块用灰浆的粘结强度的标准试验方法
【标准号】:ASTMC952-1991
【标准状态】:作废
【国别】:美国
【发布日期】:1991
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:ASTM
【标准类型】:()
【标准水平】:()
【中文主题词】:粘结强度;施工材料;灰浆;试验;砖石工程;建筑
【英文主题词】:construction;mortars;constructionmaterials;adhesivestrength;masonry;testing
【摘要】:
【中国标准分类号】:Q13
【国际标准分类号】:91_100_10
【页数】:8P;A4
【正文语种】:英语