Abstract
We investigate the development of wormholes in laboratory‐scale fractures using three‐dimensional numerical simulations. Well‐controlled initial conditions, involving a small perturbation near the inlet of an otherwise flat fracture aperture field, were used to make a systematic study of the effects of flow rate and reaction rate on the aperture evolution. We find at least two characteristic wormhole shapes, which can be grouped within a phase diagram in the space of Péclet and Damköhler numbers. We investigate how this phase diagram depends on fracture geometry, specifically the length (L) and width (W) in comparison to the initial aperture (h0). This information is used to determine an effective Damköhler number that leads to a Péclet and length‐independent phase boundary between wormholes and uniform dissolution. We relate these observations to experimental studies of wormhole formation in dissolving fractures.
