資源描述:
《汽液固多相流蒸發(fā)防除垢實驗研究》由會員上傳分享,免費在線閱讀,更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫。
1、河北工業(yè)大學(xué)碩士學(xué)位論文汽液固多相流蒸發(fā)防除垢實驗研究姓名:鐘宏偉申請學(xué)位級別:碩士專業(yè):化學(xué)工藝指導(dǎo)教師:張少峰2003.2.1型苧士些盔蘭苧±蘭竺笙苧———————————————————一汽液固多相流蒸發(fā)防除垢實驗研究摘要本文從理論和實驗兩個方面較深入研究了汽液固多相流態(tài)化技術(shù)對換熱管中硫酸鈣溶液結(jié)垢的影響,探討了三相循環(huán)流化床蒸發(fā)器的防、除垢機理,對其防除垢和強化傳熱性能做了進一步考察,針對固體顆粒對硫酸鈣結(jié)垢誘導(dǎo)期的影響進行了研究,并與不加入固體顆粒的實驗結(jié)果進行了比較,同時對結(jié)垢誘導(dǎo)期
2、的確定方法進行了改進。實驗結(jié)果表明:惰性固體顆粒的加入不僅大大地延長了結(jié)垢誘導(dǎo)期,達到了防垢的目的,而且強化了傳熱,除垢效果明顯。加入固體顆粒后的結(jié)垢誘導(dǎo)期要比未加顆粒的結(jié)垢誘導(dǎo)期延長將近5倍;加入固體顆粒濃度越大,傳熱效果越好;大粒徑顆粒要比小粒徑顆粒的傳熱效果好;加人的顆粒在較高速下要比低速情況下傳熱效果好。本文對結(jié)垢過程進行了理論分析,得出了不加固體顆粒和加入固體顆粒時硫酸鈣結(jié)垢率的計算公式,數(shù)據(jù)顯示,理論結(jié)果與實驗結(jié)果比較吻合。關(guān)鍵詞:三相流,防除垢,誘導(dǎo)期,強化傳熱,結(jié)垢釜鎏璺璽塑墮薹壟
3、墮墮塹塞蘭竺鎣—————————————————一EXPERIMENTSTUDYOFPREVENTlNGANDREMoVINGFoULINGoN、,APOR—LIQUlD—SoLIDTHREE.PHASEFLOWlNEVAPORp汀IoNABSTRACTIn也ispaper,f缸herS1udieswerecaHiedoutfortheinnuenceofCaS04foulinginheatingtubethroughvapor-liquid-solidt}lree—phaseflows協(xié)tete
4、chllologyontheoryandexperiment.Themechanismsofpreventin疊andremovingfbulingwerediscussedinmevapo卜liquid-sol試three.phaSecifculatingnuidizedbed.Thec印abiIityofpreVentingandremoVingfoulingander山ancin2meheattransf色rwerefurtherrcviewed.Theinnuenceofinduction
5、periodofCaS04foulingfbmvapor-liquid—s01idthree—phaSeflowstatetecllIloIogywasstudied,andtheresultwascomparedwithmatOfexperimentwithoutpanicle.Thedecidedwayoftheinductionperiodoffoulinghasbeenimproved.Theexperimen扭lrcsultsshowthattheinductionperiodoffou
6、lingcanbeprolongedbyaddingpanicles,al】dsoIjdpaniclecanpreventfouJingandenhanceheattransfeLThejnducljonperiodoffoulingwaslengthenstobenearly5timeswithsolidpaniclethanwimoutpanicleThemoreaddpanicles,memorethee仃bctofheat“aIlsferwas200d.Thee療’ectofheattra
7、nsferwasbetterWhent11ediaIneterofpanicleswasbiggeLTheefl’cctofheattmsferwasbetcerinhighspeedthalllowspeedwimaddingp刪cles.111eexperientialequationofCaS04rateofmassdepositedwithpaniclesa11dwithoutparticlcswasobtainedfbmtheoreticanalysistofouling.Theagre
8、ementbetweenpredicteda11dmeaSurcdresultsisexcellem.KEYwoRDs:three·phasenow,preVentingandremoVingfouling,inductionperiod,enhallcingtheheattrallsfer,fouling翟:!主鏨奎鎏型篁壘苧———————————————————一a——公式(4.16)中豹參數(shù)A——橫截瑟積,m‘.卜公式(4.16)孛的參數(shù)bF一離子濃度,mo兒c——濃度,k∥