Designed Porous Media
This chapter reviews a series of developments that point in the direction of applying porous media concepts to the description, simulation and optimization of compact systems with complex flow structures, see Bejan et al. . Compact and miniaturized heat exchangers are primary examples of this trend. Other examples are chemical reactors, fiber filters, brush seals, and the modeling of micro-segregation during the solidification of alloys. The new aspect highlighted by these developments is that flow structures are optimized so that flow systems exhibit maximum global performance subject to global constraints. Optimization of flow structure means that in the beginning the flow geometry is free to change. The system is free to morph. Global performance is achieved through the generation of flow architecture, see Bejan . In this way the flow structure becomes a porous medium with purpose, i.e. a designed porous medium.
KeywordsHeat Exchanger Natural Convection Rayleigh Number Heat Transfer Rate Heat Mass Transfer
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