| 摘要 |
<p>In a shell (1) which is open at its lower and upper ends is accommodated a fan (2) and a frustoconical wall (3) is fixed to the shell (1) in the vicinity of the lower end of the latter and surrounds the shell, the distance between the wall and the shell increasing as the wall extends away from the said lower end of the shell. Supports (5) are provided, these being intended to rest on the upper edge of a vessel to be cooled and to support the frustoconical wall (3) so that, since the shell extends inside the vessel to be cooled, a peripheral space (7) is provided between the upper edge of the vessel and the upper end of the frustoconical wall (3). <IMAGE></p> |
