Transition from natural-convection-controlled freezing to conduction-controlled freezing

Journal Article · Sun Feb 01 04:00:00 EST 1981 · J. Heat Transfer; (United States)

DOI:https://doi.org/10.1115/1.3244435· OSTI ID:6086556

Sparrow, E M; Ramsey, J W; Harris, J S

Experiments were performed to study the transition between freezing controlled by natural convection in the liquid adjacent to a freezing interface and freezing controlled by heat conduction in the solidified material. The freezing took place on a cooled vertical tube immersed in an initially superheated liquid contained in an adiabatic-walled vessel. At early and intermediate times, temperature differences throughout the liquid induce a vigorous natural convection motion which retards freezing, but the temperature differences diminish with time and natural convection ebbs. At large times, the freezing rate is fully controlled by heat conduction in the solidified material. The frozen specimens for short and intermediate freezing times are smooth-surfaced and tapered, while those for large times are straight-sided and have surfaces that are overlaid with a thicket of large discrete crystals. These characteristics correspond respectively to those of natural-convection- controlled freezing and conduction-controlled freezing. At early times, the measured mass of the frozen material is identical to that for natural-convection-controlled freezing and conduction-controlled freezing. At early times, the measured mass of the frozen material is identical to that for natural-convection-controlled freezing. At later times, the frozen mass tends to approach that for conduction-controlled freezing, but a residual deficit remains.

• Research Organization: Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minn. 55455
• OSTI ID: 6086556
• Journal Information: J. Heat Transfer; (United States), Journal Name: J. Heat Transfer; (United States) Vol. 103:1; ISSN JHTRA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
ALKANES
CONVECTION
ENERGY TRANSFER
FREEZING
HEAT TRANSFER
HYDROCARBONS
INTERFACES
MEDIUM TEMPERATURE
NATURAL CONVECTION
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PARAFFIN
TEMPERATURE DISTRIBUTION
THERMAL CONDUCTION
WAXES