環(huán)形淺液池內(nèi)中等Pr數(shù)流體熱毛細(xì)—浮力對(duì)流.pdf

1、重慶大學(xué)碩士學(xué)位論文環(huán)形淺液池內(nèi)中等Pr數(shù)流體熱毛細(xì)—浮力對(duì)流姓名：商奇?zhèn)ド暾?qǐng)學(xué)位級(jí)別：碩士專業(yè)：熱能工程指導(dǎo)教師：李友榮20060501重慶大學(xué)碩士學(xué)位論文英文摘要IIABSTRACTIndertounderstthenatureofthermocapillarybuoyancyconvectioninadifferentiallyheatedannularpoolwiththeouterheatedcontainerofradius

2、ro=40mmtheinnercooledcylinderrithatisvariable(ri=(520)mm)anadjustabledepthd=0.5–1.5mm.Thetopbottomareassumedtobeadiabatic.Weconductedaseriesofunsteadytwodimensionalnumericalsimulationswiththefinitevolumemethod.Thepoolwas

3、filledwiththe0.65cStsiliconeoil(PrtlnumberPr=6.7).Resultsshowedthat:1)Theunicellularflowsteadymulticellularflowappearwhenthesmallhizontaltemperaturedifferenceisestablishedbetweenthelateralwallsofthepool.Thegreatmassoftem

4、peraturesisinthethermalboundaryclosetothelateralwalls.Withthetemperaturedifferenceincreasedtheconvectionwillbecomeunstabletransfmintodifferentoftheoscillatyflow.2)Thesteadyflowisreplacedbythehydrothermalwavewhenthetemper

5、aturedifferenceexceedthecriticaltemperaturedifference.Thehydrothermalwaveitselflooksasasuccessionofthecellsmovingfromthecoldsidetowardsthehotside.Theamplitudefrequencyofthehydrothermalwaveisvariouswiththedifferenttempera

6、turedifference.Ifthetemperaturedifferencecontinuestoincreasetheflowwillbecomeverycomplex.thehydrothermalwavewillbereplacedbyachaosflowthatitlooksrulelessisdifferentfromhydrothermalwave.3)Intheannularpoolwiththeincreaseof

7、thedepthofannularpoolthecriticaltemperaturedifferencereducesthenumberofrollsinthepoolthefrequencyofthehydrothermalwavebecomesmalltheamplitudeaugments.4)TheratiooftheinnerouterradiusCr=riroeffectsthecriticalconditionsofin