Understanding the displacement dynamics in capillarity driven two-phase flow in packed bed architectures is of fundamental importance. In this work, the role of mesoscale physics due to the underlying capillarity-wettability interaction on the two-phase flow in a sphere-packed architecture is presented. The influence of different pore surface wettability, porosity and pressure gradient on the two-phase flow behavior has been studied. The mesoscale study exhibits interesting pattern formations due to the invasion of a non-wetting fluid and surface adherence owing to the underlying wettability-capillarity characteristics. The emergence of finger like invasion pattern in a hydrophobic architecture is observed while a stable fluid front predominates in a hydrophilic structure. This study further reveals that a hydrophilic architecture is prone to elevated saturation limit for the invading fluid, while a larger pressure gradient can promote pronounced finger-like patterns. (C) 2019 Elsevier Ltd. All rights reserved.