A theoretical and experimental study was performed to examine the water spr
ay evaporation method for ice particle production. The conditions for the f
ormation of ice particles were investigated theoretically by the diffusion-
controlled evaporation model. The prediction by the model was proved to agr
ee relatively well with experiments. The production of cold storage heat wi
ll increase almost proportionally to the number of spray nozzles because no
substantial difference was found in the mean droplet size of the overlappe
d sprays from twin nozzles. Finally, based on the results, the vacuum chamb
er was designed, and spherical ice particles of size below 300 mu m were ex
perimentally obtained by spraying water droplets of ambient temperature in
the vacuum chamber where pressure is maintained below the freezing point of
water. From the experiment for producing ice particles, it was found that
the spray flow rate influences the performance of the system mon than the p
osition of spray nozzle. (C) 2000 Elsevier Science Ltd. All rights reserved
.