Gas migration regimes and outgassing in particle-rich suspensions

Julie Oppenheimer, Alison Rust, Katharine Cashman, Bjornar Sandnes

Research output: Contribution to journalArticle (Academic Journal)peer-review


Understanding how gasses escape from particle-rich suspensions has important applications in nature and industry. Motivated by applications such as outgassing of crystal-rich magmas, we map gas migration patterns in experiments where we vary (1) particle fractions and liquid viscosity (10–500 Pa s), (2) container shape (horizontal parallel plates and upright cylinders), and (3) methods of bubble generation (single bubble injections, and multiple bubble generation with chemical reactions). We identify two successive changes in gas migration behavior that are determined by the normalized particle fraction (relative to random close packing), and are insensitive to liquid viscosity, bubble growth rate or container shape within the explored ranges. The first occurs at the random loose packing, when gas bubbles begin to deform; the second occurs near the random close packing, and is characterized by gas migration in a fracture-like manner. We suggest that changes in gas migration behavior are caused by dilation of the granular network, which locally resists bubble growth. The resulting bubble deformation increases the likelihood of bubble coalescence, and promotes the development of permeable pathways at low porosities. This behavior may explain the efficient loss of volatiles from viscous slurries such as crystal-rich magmas.
Original languageEnglish
Number of pages13
JournalFrontiers in Physics
Issue number60
Early online date26 Jul 2015
Publication statusPublished - 12 Aug 2015

Fingerprint Dive into the research topics of 'Gas migration regimes and outgassing in particle-rich suspensions'. Together they form a unique fingerprint.

Cite this