| 摘要 |
A turnable propeller assembly (3) which can be turned around a vertical axis for steering a vessel comprises an annular propeller nozzle (7) located so that the axial distance (c) from the leading edge (12) of the nozzle to the middle plane of the propeller (9) is between 0.70 and 0.85 times the length (b) of the propeller nozzle (7). To allow the propeller device (3) in any orientation to be locatable inside a well (14) at the bottom (2) of the vessel (1), when not in use, the propeller nozzle (7) lies close to the turning axis (13) of the propeller device (3) and the diameter (D2) of the well (14) is substantially 1.6 times diameter (d) of the propeller. Alternatively, if the propeller device (3) is to be accommodated in a predetermined relative orientation a diameter (D2) of substantially 1.35 times diameter (d) of the propeller (9) is sufficient. <IMAGE> |
