| 摘要 |
The propulsion unit comprises a hollow strut having an upper portion (22) with an upper end portion (100) passing through a passage (P1) formed between a first outer bottom (11) and a second inner bottom (12) in a vessel (10). The upper end portion (100) is rotatable supported with a slewing bearing (300) and sealed with a slewing seal (200) towards the vessel (10). The cooling arrangement comprises a cooling air duct system (400, 410, 500, 510), at least one fan (600) and at least one cooling unit (700). The slewing seal (200) comprises an upper slewing seal (210) and a lower slewing seal (220) at a vertical distance (H1) from each other with a space (800) formed between the slewing seals (210, 220). The upper end portion (100) comprises openings (O1) opening into the space (800) between the slewing seals (210, 220). A first cooling air duct (400) is directed to the space (800) between the upper slewing seal (210) and the lower slewing seal (220), whereby cooling air (L1) can be circulated through the first cooling air duct (400) into the space (800) between the upper slewing seal (210) and the lower slewing seal (220) and further through the openings (O1) in the upper end portion (100) to the interior of the strut (21) or return air (L2) can be circulated from the strut (21) in the opposite direction. |
