Analysis of entropy generation of ferrofluid flow in the microchannel with twisted porous ribs: The two-phase investigation with various porous layers

Heat sinks arc always in the center of electronic cooling researchers' attention. Microchannels, due to their increased surface and better thermal performance than that of normal heat sinks were used in electronic cooling devices. In this numerical investigation, the first and second laws of the thermodynamic impact of twisted porous ribs on the microchannel were studied. The effects of the Reynolds number and volume fraction of nanoparticles were investigated. The range of Reynolds number was 250 to 1000. All types of the microchannel in this study consisted of a clear microchannel, a twisted porous ribbed microchannel with two and three layers of twisted porous ribs. The results show that by inserting porous ribs, the local cross-section decreases, and the local Reynolds number increases. Also, twisted porous ribs are the cause of nanofluid flow circulation and make the heat transfer coefficient greater. Increasing the porous layer from one layer to three layers has an increasing effect on the heat transfer coefficient, and the friction factor and increasing the so is the reason for increasing the friction factor. Finally, the microchannel with triple layers of twisted porous ribs has better performance in total entropy generation, and by inserting twisted porous ribs, the entropy generation decreases. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The study focused on the thermal performance of microchannels with twisted porous ribs and investigated the impact of Reynolds number and nanoparticle volume fraction. Results showed that inserting porous ribs increased local Reynolds number and circulation of nanofluid flow, leading to higher heat transfer coefficient. Increasing the number of porous layers enhanced heat transfer coefficient but also increased friction factor. Triple layers of twisted porous ribs in microchannels showed better performance in total entropy generation.