STUDY OF TURBULENT FLOW IN RECTANGULAR CHANNEL WITH INCLINED BAFFLES

Document Type : Original Article

Authors

Mechanical Power Engineering Department, Faculty of Engineering, Menoufiya University Shebin EA-Kom, EGYPT

Abstract

Experimental and numerical studies investigate the pressure recovery coefficient along the wall of
a rectangular channel fitted by inclined-perforated and solid baffles. Two baffles of same overall
size are used in the experiment. The upstream baffle is attached to the top surface, while the
position, orientation, and the shape of the other baffle are varied. Different inflow Reynolds
number for this study is tested and ranged between 71,000 and 122,500. Experimental results show
that the pressure recovery distribution is strongly depended on the position, orientation, and
geometry of the second baffle plate. The pressure drop goes down with an increase in the
Reynolds number, but its value depends on the arrangement of baffles. The pressure drop is much
higher for two inclined baffles (one perforated on the upper wall and one solid on the lower wall).
For the sake of numerical simulation, the turbulent governing equations are solved by a control
volume-based finite difference method and using the standard as well as the RNG k- E
turbulence model associated with wall function to describe the turbulent structure. A modification
includimg the effect of streamline curvature is considered in the turbulence model. The velocity
and pressure terms of momentum equations are solved by SIMPLE (semi-implicit method for
pressure-lied equation) method. Satisfied comparisons are achieved to verify the turbulence
model used. The results show that the wall pressure recovery coefficient is strongly affected by the
geometry and location of baffles in the duct. Also, the comparisons of the numerical results given
by using turbulence models indicate the quality of the k - E including the streamline curvature in
the turbulence model

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