外文翻译-广义比例粘性阻尼矩阵识别

毕业设计（论文）外文文献翻译题目广义比例粘性阻尼矩阵识别学生姓名学号学部（系）机械与电气工程学部专业年级09机械设计及其自动化4班指导教师职称或学位博士生导师2013年4月22日外文文献翻译（译成中文1000字左右）【主要阅读文献不少于5篇，译文后附注文献信息，包括作者、书名（或论文题目）、出版社（或刊物名称）、出版时间（或刊号）、页码。提供所译外文资料附件（印刷类含封面、封底、目录、翻译部分的复印件等网站类的请附网址及原文）】EXPERIMENTALIDENTIFICATIONOFGENERALIZEDPROPORTIONALVISCOUSDAMPINGMATRIXABSTRACTASIMPLEANDEASYTOIMPLEMENTALGORITHMTOIDENTIFYAGENERALIZEDPROPORTIONALVISCOUSDAMPINGMATRIXISDEVELOPEDINTHISWORKTHECHIEFADVANTAGEOFTHEPROPOSEDTECHNIQUEISTHATONLYASINGLEDRIVEPOINTFREQUENCYRESPONSEFUNCTIONFRFMEASUREMENTISNEEDEDSUCHFRFSAREROUTINELYMEASUREDUSINGTHESTANDARDTECHNIQUESOFANEXPERIMENTALMODALANALYSIS,SUCHASIMPULSETESTTHEPRACTICALUTILITYOFTHEPROPOSEDIDENTIFICATIONSCHEMEISILLUSTRATEDONTHREEREPRESENTATIVESTRUCTURES1AFREEFREEBEAMINFLEXURALVIBRATION,2AQUASIPERIODICTHREECANTILEVERSTRUCTUREMADEBYINSERTINGSLOTSINAPLATEINOUTOFPLANEFLEXURALVIBRATION,AND3APOINTCOUPLEDBEAMSYSTEMTHEFINITEELEMENTMETHODISUSEDTOOBTAINTHEMASSANDSTIFFNESSMATRICESFOREACHSYSTEM,ANDTHEDAMPINGMATRIXISFITTEDTOAMEASUREDVARIATIONOFTHEDAMPINGMODALDAMPINGFACTORSWITHTHENATURALFREQUENCYOFVIBRATIONTHEFITTEDVISCOUSDAMPINGMATRIXDOESACCOMMODATEFORANYSMOOTHVARIATIONOFDAMPINGWITHFREQUENCY,ASOPPOSEDTOTHECONVENTIONALPROPORTIONALDAMPINGMATRIXITISCONCLUDEDTHATAMOREGENERALIZEDVISCOUSDAMPINGMATRIX,ALLOWINGFORASMOOTHVARIATIONOFDAMPINGASAFUNCTIONOFFREQUENCY,CANBEACCOMMODATEDWITHINTHEFRAMEWORKOFSTANDARDFINITEELEMENTMODELINGANDVIBRATIONANALYSISOFLINEARSYSTEMSDOI101115/129804001INTRODUCTIONALLSTRUCTURESEXHIBITDAMPINGWHENSUBJECTEDTOVIBRATIONSSTEADYSTATEHARMONICVIBRATIONCANBEVIEWEDASACYCLICALEXCHANGEOFENERGYFROMELASTICPOTENTIALENERGYTOKINETICENERGYSUCHANENERGYEXCHANGEMECHANISMISNOTCOMPLETELYEFFICIENTINTHESENSETHATTHESTRUCTUREWOULDLOSESOMEMECHANICALENERGYINEACHCYCLETHEENERGYISCONVERTEDINTOOTHERTHERMODYNAMICALLYIRREVERSIBLEFORMSSUCHASHEATTHESPECIFICWAYSINWHICHVIBRATIONENERGYISDISSIPATEDAREDEPENDENTONTHEUNDERLYINGPHYSICALMECHANISMS,WHICHARENUMEROUS,COMPLEX,ANDOFTENNONLINEAR1,2FOREXAMPLE,MODELINGDAMPINGDUETOFRICTIONATJOINTSINATYPICALBUILTUPSTRUCTURESUCHASANAIRCRAFTWINGORANAUTOMOTIVEBODYISBEYONDTHEREACHOFTHECURRENTSTATEOFTHEART3CONSIDERABLEDIFFICULTIESARISEWHENDAMPINGMODELSOTHERTHANVISCOUSARECONSIDERED4GIVENTHECOMPLEXITYINDETAIL,ITISNOTSURPRISINGTHATFAIRLYSIMPLEVISCOUSDAMPINGMODELSTHATACCOUNTFORTHEOVERALLAMOUNTOFENERGYLOSSHAVEGAINEDWIDEPOPULARITYAMONGENGINEERSPROPORTIONALORRAYLEIGHDAMPINGISONESUCHENGINEERINGMODELTHEORIGINSOFTHISMODELCANBETRACEDTOTHEWORKSOFLORDRAYLEIGH5IN1877THEEQUATIONOFMOTIONOFAVISCOUSLYDAMPEDSYSTEMISEXPRESSEDBYWHEREM,C,ANDKARE,RESPECTIVELY,THENNMASS,VISCOUSDAMPING,ANDSTIFFNESSMATRICES,FTISTHEAPPLIEDFORCINGFUNCTION,ANDQTISTHEDYNAMICDISPLACEMENTRESPONSEIFTHESYSTEMWEREUNDAMPED,THENEQ1COULDBESOLVEDVERYEFFICIENTLYUSINGTHETECHNIQUESOFMODALANALYSIS611INTHISCASETHEUNDAMPEDMODES,ALSOKNOWNASCLASSICALNORMALMODES,SATISFYANORTHOGONALITYRELATIONSHIPWITHRESPECTTOTHEMASSANDSTIFFNESSMATRICES,ASEXPRESSEDBYHEREMODESARENORMALIZEDACCORDINGTOEQ2ANDTHEEIGENVALUESAREARRANGEDSUCHTHATTHEABOVE“MODAL”ANALYSISSIGNIFICANTLYSIMPLIFIESTHEDYNAMICANALYSISBECAUSECOMPLEXMULTIPLEDEGREEOFFREEDOMMDOFSYSTEMSCANBEEFFECTIVELYTREATEDASACOLLECTIONOFSINGLEDEGREEOFFREEDOMOSCILLATORSTOINCLUDEDISSIPATIONINTHEMODALANALYSISOFNONCONSERVATIVESYSTEMS,WHICHMOSTOFTHEREALSTRUCTURESARE,ITISCONVENIENTTOASSUMEPROPORTIONALDAMPINGASPECIALTYPEOFVISCOUSDAMPINGTHEPROPORTIONALDAMPINGMODELEXPRESSESTHEDAMPINGMATRIXASALINEARCOMBINATIONOFTHEMASSANDSTIFFNESSMATRICES,THATIS,WHERE1AND2AREREALSCALARSTHISDAMPINGMODELISALSOKNOWNAS“RAYLEIGHDAMPING”OR“CLASSICALDAMPING”MODESOFCLASSICALLYDAMPEDSYSTEMSPRESERVETHESIMPLICITYOFTHEREALNORMALMODESASINTHEUNDAMPEDCASEAND,HENCE,THEJUSTIFICATIONFORAPROPORTIONALDAMPINGMODELCAUGHEYANDOKELLY12DERIVEDTHECONDITIONTHATTHESYSTEMMATRICESMUSTSATISFYSOTHATVISCOUSLYDAMPEDLINEARSYSTEMSPOSSESSCLASSICALNORMALMODESTHEYPROVEDTHATTHESERIESREPRESENTATIONOFDAMPINGREFERENCES1NASHIF,AD,JONES,DIG,ANDHENDERSON,JP,1985,VIBRATIONDAMPING,1STED,WILEY,NEWYORK2LAZAN,B,1968,DAMPINGOFMATERIALSANDMEMBERSINSTRUCTURALMECHANICS,1STED,PERGAMON,LONDON3UNGAR,EE,1973,“THESTATUSOFENGINEERINGKNOWLEDGECONCERNINGTHEDAMPINGOFBUILTUPSTRUCTURES,”JSOUNDVIB,26_1_,PP1411544PHANI,AS,2004,“DAMPINGIDENTIFICATIONINLINEARVIBRATIONS,”PHDTHESIS,CAMBRIDGEUNIVERSITYENGINEERINGDEPARTMENT,TRUMPINGTONSTREET,CAMBRIDGE,CB21PZ5RAYLEIGH,L,1877,THEORYOFSOUND,2NDED,DOVER,NEWYORK6EWINS,DJ,2000,MODALTESTINGTHEORYANDPRACTICE,2NDED,RESEARCHSTUDIES,BALDOCK,ENGLAND7MAIA,NMM,SILVA,JMM,ANDROBERTS,JB,1997,THEORETICALANDEXPERIMENTALMODALANALYSIS,ENGINEERINGDYNAMICSSERIES,RESEARCHSTUDIES,TAUNTON,ENGLAND8SILVA,JMM,ANDMAIA,NMM,1998,MODALANALYSISANDTESTINGPROCEEDINGSOFTHENATOADVANCEDSTUDYINSTITUTE,NATOADVANCEDSTUDYINSTITUTE,SERIESEAPPLIEDSCIENCE,SESIMBRA,PORTUGAL9NEWLAND,DE,1987,“ONTHEMODALANALYSISOFNONCONSERVATIVELINEARSYSTEMS,”JSOUNDVIB,112_1_,PP699610NEWLAND,DE,1989,MECHANICALVIBRATIONANALYSISANDCOMPUTATION,WILEY,NEWYORK译文广义比例粘性阻尼矩阵的识别摘要在这项工作中开发一个简单的和易于实现算法来识别一个广义的比例粘性阻尼矩阵。推荐的技术的主要优点是只有一个单一驱动点的频率响应函数（FRF）测量是必要的。这样的FRF常规测量使用标准的实验模态分析技术，如脉冲试验。推荐的识别方案的实际效用阐明基于三个有代表性的结构（1）自由梁弯曲振动中，（2）由一个准周期3悬臂结构的板插入插槽平面抗弯振动，及（3）一个点耦合梁系统。有限元方法被用来为每个系统取得质量和刚度矩阵，阻尼矩阵适合于测量粘性变化的固有振动频率（模态阻尼因素）。拟合的粘性阻尼矩阵容纳任何随频率变化的阻尼变量，而不是常规比例阻尼矩阵。可以得出结论，更推广粘性阻尼矩阵，考虑阻尼变化作为可以作为频率的函数，可容纳标准的有限元建模与振动分析的线性系统的框架内。工业部101115/129804001引言当受到振动时，所有结构具有阻尼。稳态谐波振动可以被看作是一个从弹性势能到动能周期性的能量交换。这种能量交换的机制并不完全有效在这个意义上，该结构将在每个周期中失去一些机械能。该能量被转化成其它热力学不可逆的形式，如热能。稳态谐波振动的具体方法中，振动能量被耗散是取决于底层物质的机构，它们是无数的、复杂的，通常是非线性的1,2。例如，阻尼建模由于接头处的摩擦，是达不到的当前状态的技术3，这些摩擦式在一个典型组合结构如飞机机翼或者汽车车身上3。当考虑除了粘性阻尼模型以外的模型时相当大的困难出现了4。由于细节的复杂性，这并不奇怪，相当简单的粘性阻尼模型说明能量损失的总量在工程师中已经得到广泛的认可。稳态谐波振动这种模式的起源可以追溯到到瑞利勋爵5在1877年的作品。所表示的粘性阻尼系统的运动方程为其中M、C和K分别是NN的质量的粘性阻尼和刚度矩阵，函数F（T）是所施加力的函数，Q（T）的动态位移响应。如果系统无阻尼，则方程（1）可以采用模态分析技术非常有效地解决611。在这种情况下的无阻尼模式，也被称为经典正常模式下，相对于质量和刚度矩阵满足正交关系，被下面方程所表达在此模式根据公式方程2和下面两个方程变得标准化特征值是按照这样排序另外，上述“模态”的分析显著的简化了动态分析，是因为复杂的多自由度系统可以有效地看作一个很多个单自由度系统振荡器的集合。要包括非保守系统的模态分析，大多数的实际结构的耗散，很方便的假设比例阻尼粘性阻尼的一种特