%0 Journal Article %A Nazari, Mohsen %A Mahmoudi, M. %A Aghdasi, M. %A Tamayol, A. %D 2017 %I Begell House %K porous media, natural convection, porous coating insulation, heat transfer augmentation %N 12 %P 1119-1135 %R 10.1615/JPorMedia.v20.i12.50 %T HEAT TRANSFER CARTOGRAPHY FROM A HOT ELLIPTICAL CYLINDER WRAPPED WITH A POROUS MEDIUM %U https://www.dl.begellhouse.com/journals/49dcde6d4c0809db,421e497644793a9d,36f3372b719d0058.html %V 20 %X In the present article, a comprehensive study of laminar natural convection heat transfer around cylinders of elliptical cross section wrapped with a porous medium is conducted. The presence of a porous layer around a hot cylinder may have different effects on the nature of the heat transfer and can change the heat transfer regime. The aim is to investigate and provide additional insight into the effects of physical and geometrical properties on heat transfer insulation/augmentation using a finite volume method model. Also, the critical porous layer thicknesses for heat reduction/augmentation and its dependency on other factors like conductivity ratio, Darcy number, and the cylinder aspect ratio are obtained, and the optimal design of porous media for insulation/heat transfer augmentation purposes of an elliptical hot cylinder is suggested. In addition, the range of physical properties which is suitable for applying conduction theory is obtained. The results show that there is a heat transfer augmentation/reduction transition point for different conductivity ratios and it depends on the physical properties of the coating. Also, it is shown that for an elliptical cylinder, it is possible to enhance the heat transfer rate up to 150% and to reduce it up to 30% by selecting a suitable porous layer coating. %8 2017-12-11