4252

4023

كارشناسي ارشد

تبديل انرژي

اصفهان : دانشگاه صنعتي اصفهان ،دانشكده مكانيك

1387

نه، 114، [II] ص. : مصور، نمودار

ص. ع. به : فارسي و انگليسي

علي اكبر عالم رجبي، احمد صابونچي

محمود اشرفي زاده

21/7/1387

ابراهيم شيراني، احمد صداقت

مهندسي مكانيك

ID4023

به فارسي و انگليسي : قابل رويت در نسخه ديجيتال

Abstract Corrugated ducts have been employed in a number of engineering devices to enhance heattransfer They have been successfully used in compact heat exchangers resulting in a moreeconomical use of space and material The problem of internal heat generation in computershas been solved by incorporating corrugated wall channels into their cooling system Heattransfer in gas turbines which is often enhanced by turbulence promoters and jetimpingement may also be improved by installing corrugation in their internal coolingpassages with an optimum spacing An experimental investigation of natural convection heattransfer from corrugated inclined surface by constant heat flux has been studied in this thesis Experiments were done for two different amplitude wavelength ratio of 0 18 and 0 257 Three different heat fluxes i e 6W 7W and 8W were applied on the plate which is 550mmlong x 86mm wide The experiments were done for the angle of inclinations 0 30 45 55 60 and 90 which are measured from vertical surface The results show that by increasingthe angle of inclination from 0 to 60 the wavelength of the local heat transfercoefficient variation is half of that of the wavy surface while for 65 to 90 thewavelength of the local heat transfer coefficient variation is the same as that of the wavysurface The local heat transfer coefficient is an increasing function of heat flux value Thetotal heat transfer coefficient on the wavy surface is greater than that of the flat plate with thesame projected area The total heat transfer coefficient increase as the amplitude wavelengthratio increases This is due to the increase in the heat transfer area

علي اكبر عالم رجبي، احمد صابونچي

محمود اشرفي زاده