Effect and Application of PBCF (Propeller Boss Cap Fins)

Abstract

PBCF (Propeller Boss Cap Fins) which is composed of small fins attached to propeller boss cap was proposed as a novel energy-saving device. Currently about 150 PBCFs are attached to full scale propellers and also demonstrating the PBCF effct. This paper describes principle, effect and design condition of PBCF, and also reports actual results of significant efficiency gain in full scale ships. Theses resultes lead us to believe that PBCF is an excellent energy-saving device because of its simple structure and efficiency gain of about four per cent. 1.‚Í ‚ ¶ ‚ß ‚É •MŽÒ‚ç ‚Í1986"N ˆÈ-ˆ,"•-pƒXƒN ƒŠƒ…•[ ƒv ƒ• ƒy ƒ‰ ‚Ì ‚½ ‚ß ‚Ì OEø-¦‰ü'P '• 'u ‚AE ‚µ ‚Ä,ƒv ƒ• ƒy ƒ‰OEã•" ‚Ì ƒ{ ƒX ƒL ƒƒ ƒb ƒv ‚Ì •" •ª ‚É •¬ ‚³ ‚È ƒt ƒBƒ" ‚ð •t ‰Á‚µ,ƒv ƒ• ƒy ƒ‰ ‹y ‚Ñ Ž² OEn ‚AEˆê •• ‚É ‰ñ"] ‚³ ‚¹ ‚éPBCF(Propeller Boss Cap Fins)‚Ì OE¤‹ † ŠJ "-‚ð •s ‚¢,ƒv ƒ• ƒy ƒ‰ 'P "AEŽŽ OE±,-¬ •ê ‚Ì ‰Â Ž‹ ‰» •EOEv'ª,ƒL ƒƒ ƒr ƒe •[ ƒV ƒ ‡ ƒ" ŽŽOE±, •X ‚É ‚Í 'ï •R Ž© •q ŽŽOE±,ŽÀ 'D ŽŽOE±"™‚ð •s ‚¢,•V ‚µ ‚¢ OE`