ice_fang 发表于 2010-7-13 17:15:03

DearAll,
Sorry,mybossoncegivemeapaperliteraturewhichdescribevibrationmodel.SoIshareitwithall.
Iquoteasectionforyourreference.
InVibration,devicesaremountedonadynamicshakertableandsubjecttoeitherarandomorsinusoidal-typevibrationprofile.CommonrandomvibrationtestsaremostfrequentlyspecifiedintermsofPowerSpectralDensity(PSD)levels(seebelowFigure).FigureillustratesthepossiblePSDtestprofilelevelsrelatedtoasimilarparticularuseenvironment.ThePSDfunctiondescribesthedistributionofvibrationenergywithrespecttofrequency.TheamountoftimecompressionthatcanbeaccomplishedisrelatedtothePSDtestlevelanduselevel.Estimatesoftimecompressioncanbemadeoncetheuselevelestimateandspectraldensityprofileareestablished.Thetraditionalclassicaltime-compressionmodel(MIL-STD810E)isapowerlawmodel(seebelowFigure).Inapplyingthismodel,itisimportanttounderstandthefailuremechanismsince,inarandomvibration-loadingenvironment,theresonanceofthematerialcandominatethefatiguelife.Here,maximumvibrationamplitudesandstressoccur.However,fatiguefailuresarenotalwaysdominatedbythefundamentalresonancemode.Inpractice,manyofthestresspeaksintheuseenvironmentmayfallbelowthefatiguelimitofthematerial,whileotherswillbeabovethefatiguelimit.Itfollowsthatanacceleratedlifetestbaseduponthismodelshouldinherentlybeconservative.However,becausemostofthefatiguedamageoccursatthehigheststresspeaksinboththetestandinactualuse,thedegreeofconservatismisnotexcessive.AsnotedinbelowFigure,thePSDisinunitsofG2/Hz.ThesquareoftheGstresslevelattheresonancefrequencyisdirectlyproportionaltothePSDlevel(W~G2),sothemodelcanbeputintermsofeitherrandomorsinusoidal-resonanceG-stressloading.Inthemodel,thefatigueparameterisrelatedtoexperimentalslopeofthestresstocyclestofailuredata.Thisexponentvariesdependingonthefatiguelifeofthematerialsinvolved.Forexample,thevalueofb≈5iscommonlyusedforelectronicboards.However,conservativevalueforthefatigueparameterbisabout8(e.g.,Mb=4).MILSTD-810E(514.4-46)recommendsb=8forrandomloading.

pif2216 发表于 2010-7-13 17:38:06

Thankssomuch!

yeh 发表于 2010-7-18 07:03:55

HALT模拟的振动模型与MIL-STD810E振动模型是相似的吗?

@@那@@ 发表于 2010-7-18 10:21:20

学习学习！

sounnyday 发表于 2010-7-21 11:31:38

楼上的应该是某家的试验数据吧~

小弟手边也有类似的数据
不过在IECorMIL标准上也没有这样的叙述

justinbk 发表于 2011-11-30 23:08:44

可以参考一下MIL-std-810F。回复1#pif2216

forest_sheep 发表于 2016-5-30 12:49:54

ice_fang发表于2010-7-1011:06
Example:UsingtheVibrationmodel
Problem:
Estimatethetesttimetosimulate10yearsoflifei...

第一次看见振动加速参数，学习了

lipper 发表于 2017-6-1 14:04:55

谢谢分享 ，具体出资哪里啊

Bluflower 发表于 2017-6-12 18:54:15

能共享，公式所参考的文献吗

coldd 发表于 2017-6-25 17:25:12

很久前看过一本书，《可靠性强化试验理论与应用》，可能有这类问题的说明，你买本看看
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查看完整版本: 请问谁知道Halt的随机振动怎么算加速因子