UNSTEADY NUMERICAL SIMULATION OF TURBULENT FORCED CONVECTION IN A RECTANGULAR PIPE PROVIDED WITH WAVED POROUS BAFFLES

Year 2017, , 1466 - 1477, 19.09.2017

Fakiri Fethallah

https://doi.org/10.18186/journal-of-thermal-engineering.338907

Cited By: 1

Abstract

Numerical simulations of flow and heat
transfer in a serpentine heat exchanger configuration are presented to
demonstrate application of porous media techniques in heat exchanger analyses.
In this study, steady-state 3D turbulent forced convection flow and heat
transfer characteristics in a rectangular pipe with baffles attached inside
pipe have been numerically investigated under constant wall heat flux boundary
condition. Numerical study has been carried out for Reynolds number of
20000-50,000, Prandtl number of 0.71, baffle distances h/D_h of 1/3
and 2/3, and baffle thickness e of 1/12, 2/3. It is observed that rectangular
pipe having waved baffles has a higher Nusselt number and friction factor
compared to the smooth rectangular pipe without baffles. Periodically fully
developed conditions are obtained after a certain module. Maximum thermal
performance factor is obtained for the baffle waved. Results show that baffle
distance, waved porous baffle, and Reynolds number play important role on both
flow and heat transfer characteristics. All the numerical results are
correlated within accuracy of ±2% and ±2.5% for average Nusselt number and
friction factor, respectively.

Keywords

Porous media, Horizontal Canal, Thermal transfer and matter, Model Darcy-Brinkman-Forchheimer, Forced convection, Porous baffles

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