Study of heat transfer from a square cylinder utilizing nanofluids with multiphase modeling approach

Abstract

A numerical study on the forced convective heat transfer from an unconfined heated square cylinder using nanofluids has been presented for different Reynolds number (10 - 40) and volume fractions of Al2O3 particles (0 - 5%) in water. The prime aim of this study is to highlight the influence of two-phase modeling approach on heat transfer characteristics of nanofluids. A square cylinder with a constant wall temperature higher than that of the ambient temperature is exposed to a steady, laminar and uniform flow of Al2O3-water nanofluid. The governing equations of flow and heat transfer are solved by using a finite volume method based on SIMPLE algorithm. Heat transfer characteristics of nanofluids are studied using Eulerian-mixture model approach. Theoretical models using single-phase approach available in literature have been used to determine the thermo-physical properties of nanofluids. Heat transfer characteristics of nanofluids in terms of local heat transfer coefficient, average heat transfer coefficient and heat transfer rate are studied and compared with that of the base fluid. The temperature field and flow structure around the square cylinder are visualized. © 2017 Elsevier Ltd.