ABSTRACT
This article presents a computational analysis of the turbulent flow of air in a pipe of rectangular section provided with two waved fins sequentially arranged in the top and the bottom of the channel wall. The governing equations, based on the k-ε model with Low Reynolds Number (LRN) used to describe the turbulence phenomena, are solved by the finite volume method. The velocity and pressure terms of momentum equations are solved by the SIMPLEC algorithm. The profiles of axial velocity, the velocity fields and the drag coefficient were obtained and presented for all the geometry considered and for selected sections, namely, upstream, downstream and between the two waved baffles. This contribution lead to results which were analyzed by the use of the solid, plane baffles, waved and inclined with active degrees of 0° up to 45° with a step equal to 15 degree and directed towards the left. Over the range of the study, the undulation of the baffles induced with an improvement on the skin friction of about 9.91 % in the case of α=15°, more than 16% in the other cases, and concerning the pressure loss, the undulation of the baffles was insured improvements starter from 10,43% in all cases compared with the baffles of plane form.
KEYWORDS
PAPER SUBMITTED: 2011-10-04
PAPER REVISED: 2012-04-28
PAPER ACCEPTED: 2012-05-26
THERMAL SCIENCE YEAR
2013, VOLUME
17, ISSUE
Issue 3, PAGES [801 - 812]
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