Investigation of flow interference and heat transfer characteristics of two staggered circular cylinders in cross flow

The flow and heat transfer characteristics around staggered cylinders are critical for optimizing thermal performance in engineering applications like heat exchangers. This study investigates the flow and heat transfer properties around two staggered cylinders at Re = 100 using a double-distributed lattice Boltzmann method. Eight typical flow patterns are recognized based on vortex and temperature fields, phase diagram, and St. The effects of gap flow, shear layer, vortex shedding, and wake evolution behaviors on heat transfer characteristic are discussed. Results demonstrate that when the wake is a single vortex street, the shear layer reattachment and the weaker gap flow both lead to a high temperature in the gap between the two cylinders, which subsequently adversely affects the heat transfer performance. Inversely, the vortex impingement and the stronger gap flow enhance the heat transfer performance. The deflected gap flow leads to a narrow and wide street in the wake, and the cylinder located on the opposite side of the gap flow deflection has better heat transfer performance. Furthermore, two coupled vortex streets in the wake can further improve the heat transfer performance of the cylinders. These findings provide valuable insights for enhancing thermal management strategies in engineering applications.