Passive flow control in triangular arrangement of cylinders: Role of Reynolds number, role of gap spacing, role of splitter plate

This study investigates the flow behavior around three cylinders with attached splitter plates arranged in an equilateral triangular configuration using the lattice Boltzmann method (LBM). Although previous research has focused on flow around bluff bodies without splitter plates, this study examines the effects of splitter plates on flow control. Key parameters analyzed include gap spacing ratio ( g ∗ ), splitter plate length ( L ∗ ), and Reynolds number ( R e ). Vorticity contours, drag coefficients ( C D ), lift coefficients ( C L ), and Strouhal numbers ( S t ) are computed to elucidate the relationships between vortex shedding and force coefficients. The results demonstrate that wake flow patterns, flow characteristics, and force coefficients are strongly influenced by varying g ∗ , L ∗ , and R e . C D is more affected by g ∗ , while C L and S t are more affected by L ∗ . L ∗ also plays a significant role in suppressing vortex shedding. For small L ∗ , vortices form near the cylinders, while larger L ∗ results in a streamlined flow. At small R e , a periodic flow pattern is observed, whereas at large R e , the flow exhibits a transition in vortex behavior. At small g ∗ , the geometry behaves like a solo body (SB), while with an increase in g ∗ , this effect diminishes, and a fully developed (FD) flow pattern forms for large g ∗ and L ∗ .