title: Granular fingering in fluid injection into dense granular media in a Hele-Shaw cell.
abstract: We study experimentally spontaneous pattern formation in a dry dense granular medium invaded by an aqueous glycerin solution in a radial Hele-Shaw cell. By varying the invading fluid viscosity via the weight concentration of glycerin, and by adjusting the normalized injection velocity via the injection rate and the gap size of the cell, we observe four distinct fluid-grain displacement regimes: (i) a simple radial flow regime, (ii) an infiltration-dominated regime, (iii) a grain displacement-dominated regime, and (iv) a viscous fingering-dominated regime. We argue that these displacement regimes emerge as a result of competition among the various energy dissipation mechanisms and can be classified based on the characteristic times involved in the injection process.
authors.affiliation: School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Haiying
authors.initials: H
authors.lastname: Huang
authors.forename: Fengshou
authors.initials: F
authors.lastname: Zhang
authors.forename: Patrick
authors.initials: P
authors.lastname: Callahan
authors.forename: Joseph
authors.initials: J
authors.lastname: Ayoub
mesh_terms: D055592:Biophysical Phenomena; D005990:Glycerol / Q000737:chemistry*; D008956:Models, Chemical; D012822:Silicon Dioxide / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry
chemical_list: D012996:Solutions; D012822:Silicon Dioxide; D005990:Glycerol