A series of experiments were conducted to investigate the flow field of a top-heated liquid fuel adjacent to an ice block. The experimental setup consisted of a borosilicate container containing an ice wall and a layer of n-heptane heated from above. Particle Image Velocimetry (PIV) and Background Oriented Schlieren (BOS) measurements were conducted on the liquid -phase. PIV measurements showed a surface flow toward the ice caused by surface -tension forces, which is driven by the horizontal temperature gradients on the liquid surface. A recirculation zone was observed under the free surface and near the ice. The combination of the two flow patterns caused lateral intrusion in the ice, instead of a uniform melting across ice surface. BOS measurements indicated presence of density gradients below the free surface of n-heptane and in regions near the ice block. These density gradients were created by local small-scale temperature gradients. The current experiments were conducted to explore the processes that influence the ice melting by immiscible liquid layers.
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Dynamics of ice melting by an immiscible liquid layer heated from above
A series of experiments were conducted to investigate the melting of ice adjacent to a
water-immiscible liquid layer (n-dodecane) exposed to radiation from above. The
experimental setup consisted of a borosilicate container containing an ice wall and a
layer of n-dodecane heated from above. In addition to tracking the movement of the
melt front, Particle Image Velocimetry (PIV) and Background Oriented Schlieren (BOS)
measurements were conducted on the liquid-phase . Two distinct melting regimes
were found to dominate the melting process. First was the uniform melting across the
contact area with the immiscible liquid layer for low radiation levels (~1 kW/m 2 ).
Second was the lateral intrusion regime, where a depression near free surface of the
liquid forms in ice and grows laterally for radiation level greater than ~1 kW/m 2 . The
ice surface remained flat and smooth in uniform melting regime, whereas in the lateral
intrusion regime a series of rivulets were formed that carved valleys on the ice. PIV
measurements showed a surface flow toward the ice for all heat flux levels caused by
surface-tension forces. Increase of the heat flux levels caused a transition to multi-roll
structure in the flow field. This multi-roll structure, which is accompanied by a
recirculation zone near the ice, increased heat transfer coefficient near the surface of
the liquid causing lateral intrusion regime. BOS measurements indicated presence of
density gradients below the free surface of n-dodecane and in regions near ice that are
caused by local small-scale temperature gradients. The current experiments were
conducted to explore the melting dynamics and to shed light on the processes that
influence the ice melting. Implications of such mechanisms in a real-life scenario, i.e.
oil spill in ice-infested waters, needs to be explored further by using more liquids and
improved accuracy with diagnostic techniques.
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- Award ID(s):
- 1938976
- NSF-PAR ID:
- 10303812
- Date Published:
- Journal Name:
- Experimental thermal and fluid science
- ISSN:
- 0894-1777
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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