Role of entropy generation and field synergy on heat transfer from confined wavy wall

Abstract

In the present study, three-dimensional numerical investigations are carried out to find the effect of confinement due to top wall on flow and heat transfer over sinusoidal wavy wall for a fixed Reynolds number (Re) of 500. For fixed amplitude and wavelength of the wavy wall, different values of mean channel height and varying shapes of top wall have been considered. The effect of introducing waviness in top wall with respect to a plane top wall has been studied for in-phase sinusoidal and out-of-phase sinusoidal configurations. Computations are carried out by using commercial software ANSYS Fluent 16.1. Flow and heat transfer characteristics are presented in terms of Nusselt number and friction factor. Influence of secondary flows developed inside the channel on heat transfer is evaluated by calculating secondary flow intensity and field synergy angle. Irreversibilities caused due to various confinements are analyzed by calculating entropy generation due to heat transfer and friction. The variation of entropy generation rate for different top wall configurations as well as channel heights have also been presented.