Investigations on Heat and Fluid Flow in Porous Media for Industrial Applications

Abstract

The present work is twofold in the first part of the work the impact of porosity, position,and newlinevolume of porous medium on heat and fluid flow characteristics of pipe flow, which is partially newlinefilled with porous medium, are investigated using experimental and numerical techniques. Analysis newlinehas been carried out for core and annulus shape porous medium, results show that variation in newlineNusselt number between two subsequent volumes of the porous insert are about 20 % further the newlineincrease in heat transfer for same effective volume and for same porosity is on an average 30% newlinegreater for the core shaped insert when compared to the annulus shaped insert. The pressure drop newlineusing the core is 1.2 times the pressure drop using the annulus. newlineEmpirical Correlations are obtained for pressure drop against velocity for core and annular newlineconfigurations by considering the effect of porosity, bed to particle diameter ratio, particle diameter newlineusing regression analysis. Optimization of the outputs of present work, i.e. Nusselt number and newlinepressure drop are done using an artificial bee colony algorithm. newlineIn the second stage, the solution of the unsteady natural heat transfer of porous media for a newlinesquare and concave shaped cavity (cavity in its top wall in concave shape) is demonstrated. newlineBoundary conditions assumed are hot and cold for vertical wall of square cavity and hot newlinetemperature for the concave shape top surface, the remaining three walls are assumed to be adiabatic newlinefor concave shaped cavity. Streamlines and isotherms at different time intervals varying from newline0.0025- 0.09 are obtained from different Rayleigh number values for both the cavities. newlineOne of the methods to improve heat transfer increment is to produce heat exchangers with newlineexplicit shapes, like wavy-tube heat exchangers. In this study, the impact of embedding uniform newlinepermeable media on the performance of a wavy-tube heat exchanger has been investigated newline