带式输送机 外文翻译 外文文献 英文文献 输送带的二维动态特性.doc

《带式输送机 外文翻译 外文文献 英文文献 输送带的二维动态特性.doc》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、TheTwo-DimensionalDynamicBehaviorofConveyorBelts3.1.1NONLINEARTRUSSELEMENTIfonlythelongitudinaldeformationofthebeltisofinterestthenatrusselementcanbeusedtomodeltheelasticresponseofthebelt.AtrusselementasshowninFigure2hastwonodalpoints,pandq,andfourdisplacementparameterswhichdeterminethecomponentv

2、ectorx:xT=[upvpuqvq]            (1)Forthein-planemotionofthetrusselementtherearethreeindependentrigidbodymotionsthereforeonedeformationparameterremainswhichdescribesFigure2:Definitionofthedisplacementsofatrusselementthechangeoflengthoftheaxisofthetrusselement[7]:ε1=D1(x)=∫¹ods²-ds²odξ            

3、(2)2ds²owheredsoisthelengthoftheundeformedelement,dsthelengthofthedeformedelementandξadimensionlesslengthcoordinatealongtheaxisoftheelement.Figure3:StaticsagofatensionedbeltAlthoughbending,deformationsarenotincludedinthetrusselement,itispossibletotakethestaticinfluenceofsmallvaluesofthebeltsagint

4、oaccount.Thestaticbeltsagratioisdefinedby(seeFigure3):K1=δ/1=q1/8T          (3)whereqisthedistributedverticalloadexertedonthebeltbytheweightofthebeltandthebulkmaterial,1theidlerspaceandTthebelttension.Theeffectofthebeltsagonthelongitudinaldeformationisdeterminedby[7]:εs=8/3K²s             (4)whic

5、hyieldsthetotallongitudinaldeformationofthenonlineartrusselement:3.1.2BEAMELEMENTFigure4:Definitionofthenodalpointdisplacementsandrotationsofabeamelement.Ifthetransversedisplacementofthebeltisbeingofinterestthenthebeltcanbemodelledbyabeamelement.Alsoforthein-planemotionofabeamelement,whichhassixd

6、isplacementparameters,therearethreeindependentrigidbodymotions.Thereforethreedeformationparametersremain:thelongitudinaldeformationparameter,ε1,andtwobendingdeformationparameters,ε2andε3.Figure5:ThebendingdeformationsofabeamelementThebendingdeformationparametersofthebeamelementcanbedefinedwiththe

7、componentvectorofthebeamelement(seeFigure4):xT=[upvpµpuqvqµq]        (5)andthedeformedconfigurationasshowninFigure5:ε2=D2(x)=e2p1pq        (6)1oε3=D3(x)=-eq21pq1o3.2THEMOVEMENTOFTHEBELTOVERIDLERSANDPULLEYSThemovementof