Journal Article

A novel technique of heat transfer enhancement in backward-facing step flow using a flapping vortex generator

Ramanathan, Seranthian, Ravikumar, Muthaiyan, Ponmurugan, Muthusamy

2023

Overview

Backward-facing step flow is a benchmark problem that has been studied in various fields, such as airfoils, diffusers, boilers, nuclear reactors, electronic devices, and air-conditioning ducts. In this study, a rigid rectangular flapping longitudinal vortex generator was mounted at the step of the channel to investigate the fluid flow and heat transfer characteristics at three flapping frequencies (0.167, 0.25, and 0.5 Hz) in the Reynolds number range of 3000 to 8000, while maintaining at a constant heat flux. When the fluid flowed over the backward-facing step with flapping longitudinal vortex generator, a train of longitudinal vortices developed simultaneously. At a flapping frequency of 0.167 Hz, the developed high-intensity longitudinal vortices were stable and augmented the heat transfer by 38.54 % more than the smooth channel. The friction factor at 0.167 Hz was found to be 19.47 % and 25.33 % greater than at the higher frequencies of 0.25 and 0.5 Hz, respectively.

• Publisher: Korean Society of Mechanical Engineers,Springer Nature B.V,대한기계학회
• Subject: Air conditioning / Backward facing steps / Control / Diffusers / Dynamical Systems / Engineering / Flapping / Fluid dynamics / Fluid flow / Friction factor / Heat flux / Heat transfer / Industrial and Production Engineering / Mechanical Engineering / Nuclear reactors / Original Article / Reynolds number / Vibration / Vortex generators / Vortices / 기계공학