Quasi-equilibrium air-water drainage and imbibition X-ray microtomography experiments in glass bead packs followed by one-step experiments at varying flow rates

Description

A total of 65 measurements were collected during air-water two-phase flow experiments at which the capillary pressure and water saturation were measured. These measurements are labeled as AW_02 through AW_65, and AW_DryScan as the image of the dry sample before the two-phase experiments. AW_02 through AW_14 were the measurements along second imbibition obtained by imbibing water into a granular sample at a rate of 6 ml/hr after saturation and primary drainage. AW_15 through AW_27 were measurements along the second drainage curve obtained by draining water at a rate of 6 ml/hr through the sample. The third imbibition was carried out also at a pump rate of 6 ml/hr and encompasses the measurements AW_28 through AW_41. These were the quasi-equilibrium drainage and imbibition experiments. One-step experiments (quasi-equilibrium end points for drainage and imbibition experiments) were conducted on the same sample to observe the effects of different pump rates (0.5 ml/hr–8 ml/hr) on the saturation and capillary pressure in accelerated drainage and imbibition experiments. The pump rate for each one-step experiment is outlined below. The setup contained air vents that allowed us to facilitate air access directly into the imaged section during the unsaturated portions of the drainage cycles. The vents were sealed off during high saturation with tape. The experiments with air access during drainage are identified in the sequence as “tape off” below. All scans were collected on GSECAR's 13-BM-D beamline at the Advanced Photon Source, Argonne National Laboratory. AW_42: drainage 6.0 ml/hr AW_43: imbibition 0.5 ml/hr AW_44: drainage 0.5 ml/hr AW_45: overnight equilibration of AW_44 AW_46: imbibition 2.0 ml/hr AW_47: drainage 2.0 ml/hr AW_48: imbibition 4.0 ml/hr AW_49: drainage 4.0 ml/hr AW_50: imbibition 8.0 ml/hr AW_51: drainage 8.0 ml/hr AW_52: imbibition 2.0 ml/hr AW_53: drainage 2.0 ml/hr AW_54: imbibition 2.0 ml/hr AW_55: drainage 2.0 ml/hr AW_56: imbibition 0.5 ml/hr AW_57: drainage 0.5 ml/hr (tape off) AW_58: imbibition 2.0 ml/hr AW_59: drainage 2.0 ml/hr (tape off) AW_60: imbibition 4.0 ml/hr AW_61: drainage 4.0 ml/hr (tape off) AW_62: imbibition 8.0 ml/hr AW_63: drainage 8.0 ml/hr AW_64: imbibition 2.0 ml/hr AW_65: drainage 2.0 ml/hr