Experimental Study and Heat Transfer Analysis on the Boiling of Saturated Liquid Nitrogen under Transient Pulsed Laser Irradiation

(整期优先)网络出版时间:2005-01-11
/ 1
Theboilingbehavioroftheliquidnitrogen(LN2)underthetransienthighheatfluxurgentlyneedstoberesearchedsystematically.Inthispaper,thehighpowershortpulsedurationlaserwasusedtoheatthesaturatedLN2rapidly,andthehigh-speedphotographyaidedbythesparklightsystemwasemployedtotakeseriesofphotoswhichdisplayedtheprocessofLN2'sboilingbehaviorundersuchconditions.Also,aspecialtemperaturemeasuringsystemwasappliedtorecordthetemperaturevariationoftheheatingsurface.TheexperimentsindicatedthatanexplosiveboilinghappenedwithinLN2bythelaserheating,andaconventionalboilingfollowedupafterthenewly-definedchangeovertime.Byanalyzingthetemperaturevariationoftheheatingsurface,itisfoundthatthelatentheatreleasedbythecrackofthebubblesinthebubbleclusterinducedbytheexplosiveboilingisanimportantfactorthatgreatlyinfluencestheboilingheattransfermechanism.