{"title":"Thermal Load Calculations of Multilayered Walls","authors":"Bashir M. Suleiman","volume":64,"journal":"International Journal of Physical and Mathematical Sciences","pagesStart":431,"pagesEnd":436,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/2089","abstract":"Thermal load calculations have been performed for\r\nmulti-layered walls that are composed of three different parts; a\r\ncommon (sand and cement) plaster, and two types of locally\r\nproduced soft and hard bricks. The masonry construction of these\r\nlayered walls was based on concrete-backed stone masonry made of\r\nlimestone bricks joined by mortar. These multilayered walls are\r\nforming the outer walls of the building envelope of a typical Libyan\r\nhouse. Based on the periodic seasonal weather conditions, within the\r\nLibyan cost region during summer and winter, measured thermal\r\nconductivity values were used to implement such seasonal variation\r\nof heat flow and the temperature variations through the walls. The\r\nexperimental measured thermal conductivity values were obtained\r\nusing the Hot Disk technique. The estimation of the thermal\r\nresistance of the wall layers ( R-values) is based on measurements\r\nand calculations. The numerical calculations were done using a\r\nsimplified analytical model that considers two different wall\r\nconstructions which are characteristics of such houses. According to\r\nthe obtained results, the R-values were quite low and therefore,\r\nseveral suggestions have been proposed to improve the thermal\r\nloading performance that will lead to a reasonable human comfort\r\nand reduce energy consumption.","references":"[1] R.Butler The computation of heat flows through multi-layer slabs,\r\nBuilding and Environment , 19 (3), pp. 197-206, 1984.\r\n[2] R., M Yumrutas. Unsa, M Kanog\u252c\u00f3, Periodic solution of transient heat\r\nflow throw through multilayer walls and flat roofs by complex finite\r\nFourier transform technique, Building and Environment 40 (3), pp.\r\n1117-1126, 2005.\r\n[3] M.F Zedan. and A.M Mujahid., An efficient solution for heat transfer in\r\ncomposite walls with periodic ambient temperature and solar radiation,\r\nInternational Journal of Applied Energy 14 (2), pp. 83-97, 1993.\r\n[4] C.Lombard and E. H. 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