| 摘要 |
A drive system for a watercraft has a water inlet opening (12) and a water outlet opening (13). In a propellerless pre-nozzle (10a, 10b, 10c) for the drive system, a fin system (14) is provided therein, and the fin system (14) is not provided in an inlet region in order to further improve drive efficiency. The pre-nozzle (10a, 10b, 10c) is asymmetrically arranged along a circumferential direction. |
