Fully-Developed Flow in a Furrowed Wavy Channel: Characterization of Unsteady Flow Regimes and Its Effect on Thermal-Hydraulic Performance

Abstract

Numerical study is done at various Reynolds numbers (100–2000), for periodically fully developed flow and heat transfer in five geometrically different wavy channels. Time signal analysis is done to distinguish various unsteady flow regimes and a flow regime map is proposed; demarcating steady, two types of periodic as well as quasi-periodic, and chaotic flow regimes. Temporal variation of flow structure and Nusselt number as well as friction factor are presented – in the various unsteady regimes – and discussed for a unified cause-and-effect study. Effect of different flow regimes on the thermal-hydraulic performance of wavy as compared to plane channel is presented. Effect of Prandtl numbers (0.01–100) is also studied.

The authors are thankful to Prof. S. V. Prabhu, Indian Institute of Technology Bombay (India), for his comments and discussions.