## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Numerical simulation of convective heat transfer coefficient in channel with corrugated walls

**ABSTRACT**

The present work is a contribution to study of convective heat transfer coefficient inside a rectangular channel with corrugated walls. Triangular, square and rectangular shaped configurations were studied for a range of geometric parameters during simulation. The Navier-Stokes equations were numerically solved using the finite volume method through the Easy CFD_G package code in its V.4.1.0 version. With prescribed temperatures and velocities, the model predicts the behavior of the airflow inside the device. The temperature and velocity distributions are first predicted. From these distributions, the convective heat transfer coefficients along the surface of the objects placed inside the system are determined. Also, from the pressure distribution, the pressure drops along the channel are predicted. The results show that the triangular corrugated-shaped configuration with h = 5 [cm] and α = β = 60° enable to obtain the best value of convective heat transfer coefficient on the surface of the objects which is 2.70 [Wm-2°C-1] resulting in a pressure drop of 0.11 [Pa], while for parallel-plate channel configuration this same coefficient is 1.12 [Wm-2°C-1]. The energy balance enabled to conclude that the energy gain by convection air/objects is superior to the air pump energy to overcome the pressure drop.

**KEYWORDS**

PAPER SUBMITTED: 2015-06-15

PAPER REVISED: 2016-01-23

PAPER ACCEPTED: 2016-01-23

PUBLISHED ONLINE: 2016-04-09

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