Numerical simulations of Newtonian fluid flow through a suddenly contracted rectangular channel with two different types of baffle plates

Numerical analysis of turbulent air flow structure through a rectangular channel along with multiple and different types of baffle plates has been performed, which is an important issue for heat exchangers and for that the flow characteristics and pressure drop are need to be identified. Finite Volume Method are employed to solve the governing equations using FLUENT with the Standard k - epsilon turbulence model. The present study has been validated at Re = 87,300 with the studies of Dermitini et al. The aim of this study is to investigate the dynamic behavior of turbulent air flow, baffle height, baffle thickness and arrangement of baffle in different locations for high values of Re = 88,000. Moreover, flow structure and pressure drop characteristics are discussed in the presence of trapezoidal and plane shape baffles. Normalized velocity profiles and skin friction coefficients have been studied at different locations for trapezoidal and plane baffle plates. Finally, it has been concluded that pressure drop attains its maximum value at the upstream of the channel and minimum value at the downstream of the channel for both the plane and trapezoidal shape baffles. It is ensured that in trapezoidal case axial velocity is higher than plane baffle when four baffles are alternately placed at lower and upper walls. Furthermore, it has also been revealed that the separation of boundary layer is influenced by baffle height (h) and baffle thickness (b). At x = 0.170 m, normalized velocity profiles (u/u0) are presented for wide range of Reynolds number, Re is an element of [44,000 - 176,000] to reveal that increase of Re causes the increase in vortexes.