An Experimental-Theoretical Study on Static Batch Sublimation with
Laminar Flow and Constant Wall Temperature
Abstract
The major features of a static batch sublimation process over a hot
plate with constant temperature were investigated in an
experimental-theoretical study. An experimental apparatus with a
real-time display was built to sublimate dry ice blocks of different
sizes, in either circular or rectangular geometries. When temperature of
the hotplate was changed from -30 to 200 oC, heat transfer coefficient
“hsub” decreased from 126 to 70 W/m2K, while thermal flux increased,
linearly. Weight and area of the block had a positive/negative effects
on heat transfer, respectively. In theoretical part, two “linear-
gradient” and “cubic” models were developed by a combined
mass-momentum-energy balance. The latter used Von Karman temperature
profile, and in cases of circular and rectangular geometries could
estimate “hsub” with 17.8 and 13.5 % average error. Linear-gradient
was analytic, with similar accuracy in the circular case. The developed
model are especially useful for design of sublimation equipment in
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