Abstract




 
   

IJE TRANSACTIONS A: Basics Vol. 29, No. 1 (January 2016) 109-117    Article in Press

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  NUMERICAL STUDY OF NATURAL CONVECTION HEAT TRANSFER IN A HORIZONTAL WAVY ABSORBER SOLAR COLLECTOR BASED ON THE SECOND LAW ANALYSIS
 
B. M. Ziapour and F. Rahimi
 
( Received: February 11, 2015 – Accepted: January 28, 2016 )
 
 

Abstract    Literature about entropy generation analysis of a wavy enclosure is scare. In this paper. a FORTRAN cod using an explicit finite-volume method was provided for estimating the entropy production due to the natural convection heat transfer in a cosine wavy absorber solar collector. The volumetric entropy generation terms both the heat transfer term and the friction term were straightly calculated. The solution was conducted assuming the isothermal boundary conditions of the absorber and the cover of solar collector. the results were obtained for Rayleigh number from 100 to 100000. The simulation results were compared with a flat plate absorber. It was found that, with increasing of the cosine wave amplitude, the collector enclosure irreversibility decreases.

 

Keywords    Entropy generation, Finite-volume method, Natural convection, Solar collector, Wavy absorber

 

چکیده    ادبیات فن در باره تحلیل تولید آنتروپی در محفظه های موجی شکل با کمبود مواجه است. در این مقاله یک برنامه عددی به زبان فرترن و به روش حجم محدود صریح تهیه شد تا آنتروپی تولید شده در نتیجه انتقال حرارت با همرفت آزاد را درون محفظه یک کلکتور خورشیدی با صفحه جاذب به شکل موج کسینوسی تخمین زند. عبارتهای حجمی تولید آنتروپی شامل عبارتهای انتقال حرارت و اصطکاک به صورت مستقیم محاسبه شدند. حل های عددی با فرض شرایط مرزی دما ثابت برای صفحه جاذب و پوشش شیشه ای کلکتور خورشیدی بدسن آمدند. نتایج برای محدوده عدد رایلی 100 تا 100000حاصل شدند. نتایج نشان دادن که با افزایش دامنه موج کسینوسی بازگست ناپذیریها در درون محفظه کلکتور کاهش می یابد

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