Abstract :
Effectsoftubeinclinationanglesonnucleatepoolboilingheattransferofwateratatmosphericpressurehavebeeninvestigatedexperimentally.Experimentswereperformedforsevenangles(0,15,30,45,60,75,and90°)withtwotubes(12.7and19.1mmindiameter)of540mminlength.Throughthestudy,itcanbeconcludedthattubeinclinationgivesmuchchangeonnucleatepoolboilingheattransfer.Whenthetubeisnearthehorizontalandtheverticalpositions,themaximumandminimumofheattransfercoefficientsareexpected,respectively.Thedecreaseinbubbleslugformationonthetubesurfaceandeasyliquidaccesstothesurfacearethoughttobethecausesfortheenhancedheattransfer.