高強(qiáng)化柴油機(jī)活塞的熱負(fù)荷及結(jié)構(gòu)改進(jìn).pdf

1、浙江大學(xué)碩士學(xué)位論文高強(qiáng)化柴油機(jī)活塞的熱負(fù)荷及結(jié)構(gòu)改進(jìn)姓名：譚建松申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：動(dòng)力機(jī)械及工程指導(dǎo)教師：嚴(yán)兆大20000101浙江大學(xué)碩士學(xué)位論文摘要ABSTRACTThermalloadingresearchoftheheatedpartsisaveryimportantiteminICEdesignationAlotofachievementshavingbeendonebymanyresearcherssuchasthe

2、rmalboundarycondition，thermalstrengthandthermalfatigueevaluationetcInthispaperthetheorybasisofpistonthermalloadingcalculationandtheprecisionofFEcalculationresultofacertainhigh—dutydieselpistonarediscussedAccordingtothere

3、searchresultsinICEthermalloadingmanyyears，anappropriatecalculatingmodelforthepistonhasbeenestablishedTheheatconvectioncoefficientbetweenthepistoncrownandgashasbeenseparatelycalculatedbyusingdifferentexperienceformulasThe

4、syntheticaverageheatconvectioncoefficienthasbeencalculatedbymeansofindicatordiagrammethodAccordingtoheattransfertheoryandfluidturbulenttheorytheheatcorrelationbetweenthepistontopland，ringzone，skirtzoneandthecoolingwater；

5、theringcoolingoillineofpistonandcoolingoil；thepistoncarityandtheoilmisthavebeensetupFirstlythe3DpistonmodelbymeansofIdenssoRwarehasbeenestablishedthenusingtheautomaticcreatingmeshofthissoRwaretocreatethe3DFEpistonmodel，A

6、ftergettingthepreciseboundaryconditionand3Dtemperaturefield，heatfluxwiththeoriginboundaryconditionandmeasuredtemperaturefromexperiment，thethermalstressfield，deformationvalue，compoundstress(thermomechanicalstress)fieldcar

7、lbecalculatedTheresultsprovidedtheessentialdataforanal蜘ngtlledangerouszoneofpistonToreducethethermalloadingofthispiston，threekindsofcoolingstructurehavebeenofferedinthispaperAtlastthermalfatigueevaluatingmethodsofthepist