An Experimental Study Of Natural Convection Heat Transfer Through A Cavity Between Eccentric Horizontal Cylinders
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An experimental study on natural convection heat transfer across an eccentric horizontal annulus under the condition of constant surface temperature was carried out. The study included clarifying the effect of eccentricity ratio and the angular position as well as the effect of Raleigh number on the ability of the inner cylinder to heat reject. An experimental set-up was done for this purpose which consists of a cooling water tank and two aluminum cylinders, the outer diameter of the inner cylinder is(26mm), electrically heated from the inside, which represents the heating element, the inner diameter of the outer cylinder is(100mm) which represent cooling element in this set-up. The experimental study showed that the ability of the inner cylinder to transmit heat with free convection is a function to eccentricity ratio and the angular position, as well as Raleigh number, where this ability increases as angular position increases for all eccentricity ratios, while the eccentricity ratio effect depends on the angular position, where the thermal performance for the inner cylinder may be better at the location (δ=180o) for the ratio (ε=0.2), where the maximum enhancement in heat transfer coefficient was recorded as(10%) at this location in comparison with concentric annulus, whilst the location (δ=0o)for the ratio (ε=0.726) was given maximum reduction in heat transfer coefficient for the inner cylinder was recorded as (23%) in comparison with concentric annulus, whilst the coefficient of heat transfer proportional directly with Raleigh number.
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References
Ramiz, F. B., “Optimal heat transfer design for district- heating and cooling pipelines in air-filled cavities” Ph.D.thesis, Cranfield Institute of technology, Scholl of Mech. Eng. 1986.
Grigull, U.,and Hauf, W., “Natural Convection In Horizontal Cylindrical Annuli”, Proc. 3rd. Int. Heat Transfer Conf., Chicago, Paper 60, 2(1966), pp.182-95.
Kuehn, T. H. and Goldstein, R. J.; “An Experimental And Theoretical Study Of Natural Convection In The AnnulusBetween Horizontal Concentric Cylinders”, J. FluidMech., Vol. 74, part 4, pp. 695-719, 1976. DOI: https://doi.org/10.1017/S0022112076002012
Ozoe, H., Shibata T., and Churchill S., W., “NaturalConvection In An Inclined Circular Cylindrical AnnulusHeated And Cooled On It’s End Plates”, Int. J. Heat MassTransfer, Vol. 24, No.4, pp. 727-737, 1981. DOI: https://doi.org/10.1016/0017-9310(81)90016-8
Kubair, V. G. and Simha C. R. V., “Free Convection Heat Transfer To Mercury In Vertical Annuli”, Int. J. Heat Mass Transfer, Vol. 25, No. 5, pp. 399-407, 1982. DOI: https://doi.org/10.1016/0017-9310(82)90193-4
Kuehn, T. H. and Goldstein, R. J., “An ExperimentalStudy of Natural Convection Heat Transfer in Concentric and Eccentric Horizontal Cylindrical Annuli”, ASME, J.Heat Transfer, Vol. 100, (1978) pp.635-641. DOI: https://doi.org/10.1115/1.3450869
Naylor, D., Badr, H. M., and Tarasuk, J. D., “Experimentaland Numerical Study Of Natural Convection Between TwoEccentric Tubes”, Int. J. Heat Mass Transfer, Vol.32, No1. pp. 171-181, 1989. DOI: https://doi.org/10.1016/0017-9310(89)90100-2
Yunus, A. Cengel, “Heat Transfer A Practical Approach”,Mc-Graw Hill, Inc., 1998.
كريث, فز, و بوهن, م. س.و “أساسيات انتقال الحرارة”, ترجمة د.العلي, برهان محمود, الصبحة, احمد نجم, ومصطقى, بهجت مجيد, الطبعة الأولى, مديرية دار الكتب للطباعة والنشر, جامعة الموصل, 1988
البياتي, أوميد اكبر عباس, “دراسة نظرية وعملية لتاثير الارضية على انتقال الحرارة بالحمل الحر من صف من الاسطوانات الأفقية المسخنة”, رسالة ماجستير, قسم الهندسة الميكانيكية, جامعة تكريت, أب, 2004
Holman, J. P., “Experimental Methods for Engineers”, 4th Edition, McGraw-Hill, Tokyo, Japan, 1971.