Mixed convection heat transfer by nanofluids in a cavity with two oscillating flexible fins: A fluid-structure interaction approach

This study investigated the effects of two oscillating fins on the heat transfer rate and flow characteristics of a nanofluid inside a square enclosure. Both fins were attached to the hot wall and both fins oscillated at the same frequencies and amplitudes. The finite element method implemented in the arbitrary Lagrangian-Eulerian (ALE) technique was used to solve the equations describing the interactions and movements of the nanofluid and fins. Comparisons of our results and those reported in previous studies demonstrated that the modeling and numerical investigations were valid and reliable. The results showed that the increase in the heat transfer rate was due to the oscillation of the fins. In addition, the increasing trend in the heat transfer rate due to the oscillating fins decreased as the ratio of the thermal conductivity of the fins relative to the nanofluid increased. Increasing the thermal conductivity and viscosity parameters enhanced and weakened the heat transfer rate, respectively. (C) 2019 Elsevier Inc. All rights reserved.