This study investigated the characteristics of convective heat transfer and fluid flow for a heated plate surrounded by unheated plates aligned at angles to the flow direction inside a rectangular duct. The plates were arrayed in two main geometries: inline and staggered. Flow deflections within the array of aligned plates were dominated by boundary-layer separation effects and wake interactions, which in turn influenced the convection heat transfer. The heat transfer coefficient associated with the heated (instrumented) plate was determined by its position and its angle. The numerical model for the heated plate within a bank of plates was validated on experimental data for similar flow geometries and experimental conditions. The heat transfer coefficient decreased in the following rows and at an increased plate angle with respect to the direction of flow. The pressure drop across the array of plates also increased when the plate angles were increased with respect to the direction of flow velocity.