百叶窗式翅片换热器中的耦合传热(2)

.

? 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.

42重庆大学学报(自然科学版)　　　　　　　　　　　　　　　　　　　2005

年

CoupledConduction2convectiveHeatTransferintheLouvered

FinHeatExchanger

QIBo,LILong2jian,CUIWen2zhi,CHENQing2hua

(CollegeofPowerEngineering,ChongqingUniversity,Chongqing400030,China)

Abstract:Theheattransferprocessinthelouveredfinheatexchangerisanalyzed,andthecorrespondingphysicalandmathematicalmodelsonthecoupledconduction2convectiveheattransferforthelouverfingeometryareproposed.Thecontrolvolume2basedfiniteelementmethod(CVFEM)isemployedtosolvenumericallytheproblem.Thecomputedresultsrevealtheflowstructureandheattransferinthegeometryindetail.Comparedwiththeempiricalcorrelationofheattransferandfrictioncoefficientspreviouslyproposed,thecomputedresultsshowbetterconsistencywiththeexperi2mentalresults.

Keywords:louveredfinheatexchanger;coupledheattransfer;numericalsimulation

(编辑　陈移峰)

(上接第38页)

GeneralPhasorDiagramandPower2angleCharacteristicEquations

ofExtraHighVoltageLongDistanceTransmissionLine

LINLi,MOUDao2huai,SUNCai2xin

(KeyLaboratoryofHighVoltageEngineeringandElectricalNewTechnologyUndertheStateMinistryofEducation,

ChongqingUniversity,Chongqing400030,China)

Abstract:Installingcompensationequipmentsisagoodmannertoimprovelinetransmissioncapacityandmaintainpow2ersystemstabilityintheextrahighvoltage(EHV)longdistancetransmissionline.Itisofbenefittoanalysisandcontrolbydescribingtheeffectofcompensationequipmentcorrectly.Atpresent,forpredigestinganalysisorincreasingreal2timecalculatingspeed,concentratedparametercircuitmodeliswidelyusedtoanalyze500kVEHVlongdistancetrans2missionlinewhichmaycausebiggererror.Soitisnecessarytogetamorereasonablemodel.Onthebasicofvoltageandcurrentdistributedequationsofevendistributedlongdistanceline,thispaperdeducesphasordiagramandpower2anglecharacterequationsofuncompensatedlongline.Thentheauthorsanalyzetheeffectofcompensatorsanddefinetwochar2acteristicparameters,namely,equivalentimpedancexeqandvoltagecoefficientKV.AnycompensatingstatesofEHVlongdistancetransmissionline,exampleinstallingthecompensatorsinthelineornotorwhichtypeofcompensators,isdescribedbythegeneralphasordiagramandpower2anglecharacteristicequations.Furthermore,incrementcalculationequationsoftwocharacteristicparametersispresentedbythecompensatorparameterswhichmaymaketheconceptsclearandpredigestsanalysiseasily.

Keywords:extrahighvoltagetransmission;power2anglecharacteristic;equivalentimpedance;voltagecoefficient

(编辑　李胜春)

? 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.

bbs.99jianzhu.com内容：建筑图纸、PDF/word 流程，表格，案例，最新,施工方案、工程书籍、建筑论文、合同表格、标准规范、CAD图纸等内容。