Heat Transfer in a Horizontal Cylinder With Eccentric Surfaces. Issue 9 (12th June 2016)

• Record Type: Journal Article
• Authors: Malateaux, Ezequiel C.; Milanez, Luiz F.
• Is Part Of: Heat transfer engineering. Volume 37:Issue 9(2016)
• Page Start: 791
• Page End: 804
• Publication Date: 2016-06-12
• Subjects: Heat -- Transmission -- Periodicals; 621.4022
• DOI: 10.1080/01457632.2015.1080572
• Languages: English
• ISSNs: 0145-7632

Abstract

Abstract : Heat transfer in horizontal cylinders exposed to free convection and radiation is of importance in many industries. Usually this problem is treated by adopting a concentric geometry, disregarding that the external surface temperature is not uniform. If an eccentric geometry is used, the external surface temperature should have a larger variation, changing the flow around the cylinder and the heat transfer coefficient, either improving or reducing the heat transfer. A numerical analysis is presented of the heat transfer in a horizontal cylinder with an internal isothermal surface eccentric to the external surface that is exposed to air free convection and radiation. The conduction problem was solved analytically and integrated numerically, while the free convection was solved by the PHOENICS software. The parameters analyzed were the ratio of radius, the ratio between the material and air thermal conductivities, the Rayleigh number, the emissivity of the outer surface, and the eccentricity between the external and inner surfaces. The parameters of a proposed equation to estimate the total heat of an eccentric arrangement in terms of the total heat of the corresponding concentric arrangement and the ratio between the convective and conductive thermal resistances were determined for given ratios of radius and eccentricities.