Embedding multiple conical vanes inside a circular porous channel filled by two-phase nanofluid to improve thermal performance considering entropy generation

In the present work, thermal performance and entropy generation of two-phase nanofluid in a circular channel equipped with multiple conical vanes filled by porous material are studied. The vanes used in the present study are designed to be able to connect to an electric motor and can rotate (as a feature). However, in this study, only the static case of the vanes is studied. It was shown that the use of the above design can lead to increased heat transfer with an appropriate pressure drop. At a constant pumping power or when there is a limit on the flow rate, the use of the vane design can lead to more heat transfer. It is, therefore, energy-saving and can be used as a viable option for energy storage. The thermal performance illustrates that in the non-porous case, the best PEC occurs for the six rows of vanes, and for the porous case, the best PEC cases occur for three rows and six rows of vanes in Da = 10(-3). At maximum flow velocity and minimum permeability, the highest entropy generation is observed, which is affected by thermal entropy generation. Increasing the number of conical branches leads to increased entropy generation. The results show that a 100-fold reduction in permeability can increase heat transfer by up to 8%, while a three-fold increase in Reynolds number can improve heat transfer by more than 100%.

Automated summary

The study demonstrates that using specially designed vanes in a circular channel can enhance heat transfer efficiency and meet energy-saving requirements. By optimizing vane arrangement and reducing porosity, more efficient entropy generation can be achieved.