Exergy and entropy analysis of metal foams based on 2nd law of thermodynamics

Abstract

The available (exergy) and effective use (entropy generation) of energy at the end of thermodynamic processes are significantly important parameters in the design of optimum thermal system. Entropy analysis based on 2nd law of thermodynamics through various pore density metal foams placed in an asymmetrical heated horizontal channel is presented in the current work. Water flows through the channel at different flow rates (inlet velocity varies from 0.02 to 0.3 m/s). Highly porous and different pore density aluminum metal foams such as 10 (0.95), 20 (0.90), 30 (0.92) and 45 (0.90) are inserted into the channel to boost the heat transfer. Darcy Extended Forchheimer (DEF) and local thermal equilibrium (LTE) models are used for the calculation of flow and thermal variables respectively. The numerical outcomes of the examination are first confirmed by comparing with existing experimental literature results. The mean exergy Nusselt number results presented shows that the 10PPI metal foam stretches 35.41 % and 12.20 % higher thermal presentation with respect to 20PPI and 30PPI metal foam. The entropy examination showed that the 20PPI metal foam produces minimum entropy generation at a Reynolds number of 3464.32 and 10PPI metal foam shows highest presentation based on Bejan and entropy generation number.