MAKING CARBON DIOXIDE SNOW WITH OPPOSED SPIRAL FLOW SNOW HORNS

摘要

For producing and holding CO2 snow, first and second cylindrical horns (4, 6) connected to an open ended vertical discharge duct (8) to form a generally Y-shaped continuous expansion chamber. First and second nozzles (34, 36) axially positioned at the tops of the snow horns have tangential fluid discharge passages (33..35) which are mutually oppositely oriented to produce oppositely oriented spiral flows of CO2 snow within the snow horns. The two oppositely oriented spiral flows meet in a mixing region where their spiral components are cancelled, leaving only a vertical component of motion so that the snow is discharged through the vertical discharge duct by gravity. The discharged snow can be stored in a snow receiving container without blowing or wastage.