From connected pathway flow to ganglion dynamics

摘要: During imbibition, initially connected oil is displaced until it trapped as immobile clusters. While initial and final states have been well described before, here we image the dynamic transient process in a sandstone rock using fast synchrotron-based X-ray computed microtomography. Wetting film swelling subsequent snap off, at unusually high saturation, decreases nonwetting phase connectivity, which leads to fragmentation into mobile ganglia, i.e., ganglion dynamics regime. We find that addition pressure-driven pathway flow, mass transfer also occurs by sequence of correlated breakup coalescence processes. For example, meniscus oscillations caused snap-off events trigger adjacent The length scale clusters thus represents an intermediate flow regime between pore Darcy so far dismissed most upscaling attempts.