COMPARATIVE STUDY OF THE THERMO-CONVECTIVE BEHAVIOR OF A TURBULENT FLOW IN A RECTANGULAR DUCT IN THE PRESENCE OF THREE PLANAR BAFFLES AND/OR CORRUGATED (WAVED)

Abstract

This study numerically examines the behaviour of a two-dimensional turbulent flow of air in a rectangular pipe with three flat or corrugated baffles. A realizable k-ε turbulence model is used and the conservation equations are solved by the finite volume method using the SIMPLE algorithm. The study examined the dynamic and thermal behaviour of the flow by focusing on a presentation of several parameters, namely the turbulence intensity, the ratios of the friction coefficients and the Nusselt coefficients as well as the drag coefficients and thermal expansion, for all the geometry and for a Reynolds number varying from 5000 to 20000. The study showed that the presence of three baffles in a pipe governs a maximum turbulence intensity of the order of 206.49% to 110.72% for the small and the large inter-fin distance, which consequently guarantees a reinforcement of the heat exchange, of the order of 1.775 to 2.83 times compared with a smooth pipe, and on the other hand, an increase in friction with the walls of the order of 7 to 12 times. The study also revealed the existence of an optimum located between 0.14 and 0.16 m leading to the lowest friction ratio.

Keywords

• turbulence baffles
• forced convection
• planar
• corrugated