immediate implications to the design of passive geometries to manage highly wetting fuels,
cryogens, thermal fluids, and contaminated aqueous solutions for urine processing. The unique
vane gap critical wetting phenomena is greatly complicated by the presence of three-
dimensional (3-D) porous walls.
The Interior Corner Flow (ICF) experiment determines the rates of 3-D inhibition of wetting
fluids in complex containers, the dependence of the dynamical boundary conditions as a
function of geometry, and the performance of such devices as passive phase (i.e., bubble)
separators. The ICF experiments are designed to benchmark the analytical technique developed
to predict such flows. The benchmark theory aids in the design and analysis of capillary devices
for positioning liquids passively in containers in microgravity environments by controlling the
container geometry. The devices are useful in passive phase separation operations such as in
the case of tapered screen galleries for bubble-free collection and positioning of fuels for
satellites, to address propellant management aboard spacecraft. Spontaneous capillary flows in
containers of increasing complexity such as ICF determine critical transients for low-g
propellant management.
The objective of the Capillary Structure (CS) experiment is to add another critical dimension of
complexity, interconnectivity, to the ICF experiments. Liquid bearing containers can easily be
interconnected by capillary structures. The crew studies the time dependent flows as functions
of unit cell dimensions and geometry, unit cell interconnectivity, overall structure dimensions
and taper. They also investigate passive phase separation characteristics of such construct.
Capillary Structures studies full 3-D wicking at micro-scales. The flows incorporate 3-D capillary
driven corner flow networks consisting of a matrix of interconnected pores (Weislogel 2009).
PUBLICATION(S)
Weislogel MM, Chen Y, Collicott SH, Bunnell CT, Green RD, Bohman D. More Handheld
Fluid Interface Experiments for the International Space Station (CFE-2). 47th Aerospace
Sciences Meeting and Exhibit, Orlando, FL; January 5-8, 2009.
This investigation is ongoing and additional results are pending publication.