Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-26T18:30:35.241Z Has data issue: false hasContentIssue false

TOPOLOGY OF STEADY HEAT CONDUCTION IN A SOLID SLAB SUBJECT TO A NONUNIFORM BOUNDARY CONDITION: THE CARSLAW–JAEGER SOLUTION REVISITED

Published online by Cambridge University Press:  18 February 2013

R. G. KASIMOVA*
Affiliation:
German University of Technology in Oman, Muscat, Sultanate of Oman
YU. V. OBNOSOV*
Affiliation:
Institute of Mathematics and Mechanics, Kazan Federal University, Kazan, Russia
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Temperature distributions recorded by thermocouples in a solid body (slab) subject to surface heating are used in a mathematical model of two-dimensional heat conduction. The corresponding Dirichlet problem for a holomorphic function (complex potential), involving temperature and a heat stream function, is solved in a strip. The Zhukovskii function is reconstructed through singular integrals, involving an auxiliary complex variable. The complex potential is mapped onto an auxiliary half-plane. The flow net (orthogonal isotherms and heat lines) of heat conduction is compared with the known Carslaw–Jaeger solution and shows a puzzling topology of three regimes of energy fluxes for temperature boundary conditions common in passive thermal insulation. The simplest regime is realized if cooling of a shaded zone is mild and heat flows in a slightly distorted “resistor model” flow tube. The second regime emerges when cooling is stronger and two disconnected separatrices demarcate the back-flow of heat from a relatively hot segment of the slab surface to the atmosphere through relatively cold parts of this surface. The third topological regime is characterized by a single separatrix with a critical point inside the slab, where the thermal gradient is nil. In this regime the back-suction of heat into the atmosphere is most intensive. The closed-form solutions obtained can be used in assessment of efficiency of thermal protection of buildings.

Type
Research Article
Copyright
Copyright ©2013 Australian Mathematical Society

References

Australian Government Bureau of Meteorology, at: http://www.bom.gov.au/index.shtml.Google Scholar
Bejan, A., Convection heat transfer, 3rd edn. (Wiley, Hoboken, NJ, 2004).Google Scholar
Carslaw, H. S. and Jaeger, J. C., Conduction of heat in solids, 2nd edn. (Clarendon Press, Oxford, 1959).Google Scholar
Gakhov, F. D., Boundary value problems (Pergamon Press, New York, 1966).CrossRefGoogle Scholar
Kolodziej, J. A. and Strek, T., “Analytical approximations of the shape factors for conductive heat flow in circular and regular polygonal cross-sections”, Intl J. Heat Mass Transfer 44 (2001) 9991012; doi:10.1016/S0017-9310(00)00162-9.CrossRefGoogle Scholar
Lin, R.-L., “Explicit full field analytic solutions for two-dimensional heat conduction problems with finite dimensions”, Intl J. Heat Mass Transfer 53 (2010) 18821892; doi:10.1016/j.ijheatmasstransfer.2009.12.070.CrossRefGoogle Scholar
Manners, W., “Heat conduction through irregularly spaced plane strip contacts”, J. Mech. Engrg. Sci. Part C 214 (2000) 10491957; doi:10.1243/0954406001523515.CrossRefGoogle Scholar
Mason, J. C. and Handscomb, D. C., Chebyshev polynomials (Chapman & Hall/CRC, Boca Raton, FL, 2003).Google Scholar
Obnosov, Yu. V., “A generalized Milne–Thomson theorem”, Appl. Math. Lett. 19 (2006) 581586; doi:10.1016/j.ami.2005.08.006.CrossRefGoogle Scholar
Obnosov, Yu. V., “Three-phase eccentric annulus subjected to a potential field induced by arbitrary singularities”, Quart. Appl. Math. 69 (2011) 771786; doi:10.1090/S0033-569X-2011-01242-8.CrossRefGoogle Scholar
Obnosov, Yu. V., Kasimova, R. G., Al-Maktoumi, A. and Kacimov, A. R., “Can heterogeneity of the near-wellbore rock cause extrema of the Darcian fluid inflow rate from the formation (the Polubarinova-Kochina problem revisited)? Comput. Geosci. 36 (2010) 12521260; doi:10.1016/j.cageo.2010.01.014.CrossRefGoogle Scholar
Obnosov, Yu. V., Kasimova, R. G. and Kacimov, A. R., “A well in a ‘target’ stratum of a two-layered formation: the Muskat–Riesenkampf solution revisited”, Transp. Porous Media 87 (2011) 437457; doi:10.1007/s11242-010-9693-6.CrossRefGoogle Scholar
Philip, J. R., “Periodic nonlinear diffusion: an integral relation and its physical consequences”, Aust. J. Phys. 26 (1973) 513519.CrossRefGoogle Scholar
Polubarinova-Kochina, P. Ya., Theory of ground-water movement (Princeton University Press, Princeton, NJ, 1962).Google Scholar
Sailor, D. J., Hutchinson, D. and Bokovoy, L., “Thermal property measurements for ecoroof soils common in the western U.S.”, Energy Build. 40 (2008) 12461251.CrossRefGoogle Scholar
Wolfram, S., Mathematica. A system for doing mathematics by computer (Addison-Wesley, Reading, MA, 1991).Google Scholar