電站空冷風機集群效應的數(shù)值模擬.pdf

1、華北電力大學(北京)碩士學位論文電站空冷風機集群效應的數(shù)值模擬姓名：董運寧申請學位級別：碩士專業(yè)：動力工程及工程熱物理；工程熱物理指導教師：杜小澤201103華北電力大學碩卜學位論文AbstractDecadesofaxialflowfansisadoptedbydirectaircooledsystemtoprovideaircooledcondenserwithcoolingmediumItisdifferentfromtheaer

2、odynamicbehaviorofanindividualfanItisofimportancetoinvestigatetheclustereffectofthearrayofaxialflOWfansforthesafeandefficientoperationofthedirectaircooledsystemFirstlyinviewofexistingquestionaboutthefanmodelinFLUENT，thet

3、angentialvelocityisintroducedbyusingUDF’andamethodforsettingupperformancecuiveofaxialflowfansisfoundWhenthetangentialvelocityisintroducedornot，thedifierenceoftheflowfieldisobtainedbyCFDsimulationTheresultsshowthat：theflO

4、WfieldwillbechangedgreatlyifthetangentialvelocityisintroducedSOthisconditionshouldnotbeignoredintheCFDsimulationAnditisusefulfortheoptimaldesigningofaircoolingislandSecondly，theflowrateofeachfanandtheoverallflOWrateofthe

5、arrayoffansareobtainedatnoambientwindsandatvariOUSwindspeedsanddirectionsbyusingCFDsimulationTheclusterfactorofeachfanandthemacroscopicclusterfactorofthearrayoffansarecalculatedatdifferentconditionsTheresultsshowthatthec

6、lusterfactorisdifferentfromeachotherandalsepresentstheunliketrendsatnowindsandattheambientwindsTheclusterfactorofthefanthatliestotheperipheryofthearrayoffansorintheupwindoftheambientwindsisgenerallysmallAndtheclusterfact

7、oralsovarieswiththewinddirectionsThemacroscopicclusterfactordecreaseswiththeincreaseofthewindspeedsandalsovarieswidelywiththewinddirectionsThewindblowing行omtheboilerhousetotheaircooledsystemisthemostunfavorable，inwhichth

8、emacroscopicclusterfactoroftheaircooledsystemisthelowestTheclustereffectofthearrayoffansisofusefortheoptimaldesignandoperationofaxialflowfansforaircooledcondensersinpowerplantKeywords：directaircooledsystem；axialflowfan；c