Numerical Investigation of Nanofluid Flow and Heat Transfer Around a Calabash-Shaped Body

Abstract

Numerical simulation on unsteady flow and heat transfer of alumina–water nanofluids around a calabash-shaped body was performed in the present study. Improved models of drag force and Brownian force were introduced. As the reaction time of the particle perturbation is short, fluctuation in vorticity is more intense than that in temperature, and many extreme values are found. The streamline is uplifted near the separation point due to the contribution of the particle inertia, which increases the recirculation zone of the quasi-steady vortex. Fewer particles enter the vortex near the waist portion from the separation region, and relatively more particles enter the recirculation region from the reattachment zone. The local streamline is straightened and flow heat transfer is enhanced. It is shown that the variation in the Nusselt number is strongly related to the critical points along the wall.