This work introduces a simple method of exergy analysis in a typical circular porous fin. The entropy generation of any thermodynamic system provides a useful measure of the extent of irreversibility. The irreversibility causes the loss of useful work (exergy) in the system and hence the loss of exergy has to be minimized. Entropy generation is a parameter that quantifies the loss of exergy. Circular fins are relatively good heat transfer augmentation features with superior aerodynamic performance and as a result find application in some solar air heaters. In this paper, the entropy generation in a circular porous fin is calculated and its performance is compared with respect to entropy generation. Also shown in porous fins, with increase of porosity. The entropy generation number will increase; also states with porosity have higher entropy generation number than states with nonporosity ( ). Also at higher Reynolds number the effect of the on is negligible, but at lower Reynolds number the variation of the is negligible. Also we can see that with increased porosity ( ), the entropy generation ( ) will decrease. The entropy generation is calculated for circular porous fins with mass constraint. 1. Introduction The term extended surfaceis used to describe a system in which the area of a surface is increased by the attachment of fins. A fin accommodates energy transfer by conduction within its boundaries, while its exposed surfaces transfer energy to the surroundings by convection or radiation or both. Fins are commonly used to augment heat transfer from electronic components, automobile radiators, engine and compressor cylinders, control devices, and a host of other applications. Fins are used to enhance convective heat transfer in a wide range of engineering applications and offer a practical means for achieving a large total heat transfer surface area without the use of an excessive amount of primary surface area. Fins are commonly applied for heat management in electrical appliances such as computer power supplies or substation transformers. Other applications include IC engine cooling, such as fins in a car radiator. Heat and mass transfer through saturated porous media is an important development and an area of very rapid growth in contemporary heat transfer research. Although the mechanics of fluid flow through porous media has preoccupied engineers and physicists for more than a century, the study of heat transfer has reached the status of a separate field of research during the last three decades [1]. The description of heat and fluid flow through
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