[01] Mojtaba Aghajani Delavar, Corresponding Author, Faculty of Mechanical Engineering, Babol University of Technology Babol, Babol, Iran. [02] Elham Sattari, Faculty of Mechanical Engineering, Babol University of Technology Babol, Babol, Iran.

This study investigates the effect of porous media location over the natural convection heat transfer and related entropy generation inside a square cavity. A two dimensional lattice Boltzmann model with nine velocities was used to solve the problem numerically. The simulations were done for different Rayleigh numbers, porous part configurations and porosities. The main differences and gradients in fluid temperature take place near the hot and cold walls. Therefore in models which porous part was accumulated near these walls, fluid flow patterns were more affected by porous part and more variations were observed in comparison with clear case. In addition, these models were most sensitive to porosity. It was seen that the effect of porosity and porous part location on flow field increased for higher Rayleigh numbers. In all models it was illustrated that existence of porous media causes an increase in the amount of non-dimensional entropy generation.

Natural Convection, Enclosure, Entropy Generation, Lattice Boltzmann Method, Porous

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