PURPOSE: To eliminate hanging down of an air blow-off pipe, etc., to a lower space, simplify a structure, restrict blow-off pressure loss small, and improve the formation efficiency of a turning air stream.
CONSTITUTION: Blow-off air is collided with a collision plate 43 to form a surface-shaped air stream B and a turning air stream C is formed with a plurality of the surface-shaped air streams B in a predetermined direction. Spiral artificial tornados D are formed by sucking air located in the vicinity of the center of the turning air stream C. An apparatus 47 therefor includes a plurality of blow-off outlets 39 disposed on the same flat plane 33, a collision plate 43 with which a jet from the blow-off outlet 39 is collided, and a suction inlet 35 disposed on the same flat plane 33 as the blow-off outlet 39 for sucking air in the vicinity of the center of the turning air stream C.
OOTA KATSUYA
KARIKOMI MASANORI
