Figure 6. In imbibition, a significant portion of the pores (measured by the cooperativity ε_coop) are invaded by cooperative pore filling events (“overlaps”) ¹².

Lowering disorder hinders cooperativity, as demonstrated by the side panels showing two adjacent menisci with similar curvatures. At high flow rates, increasing dominance of viscous instabilities suppresses overlaps¹², decreasing ε_coop. Lines and shading show ensemble mean and standard deviation among four realizations.