Tham khảo tài liệu 'nuclear power deployment operation and sustainability part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Nuclear Naval Propulsion 25 13. Nuclear attack submarines At some time the Russian Navy operated about 377 submarines including 180 nuclear powered ones compared with 115 in the USA navy. The Russian navy operated 220 attack submarines 60 of them were nuclear powered. These included designs of the November Echo Victor and Alfa classes. The Victor class attack submarine was characterized by a deep diving capability and high speed. 14. Alfa class submarines The Alfa Class submarine is reported to have been the fastest submarine in service in any navy. It was a deep diving titanium hull submarine with a submerged speed estimated to be over 40 knots. The titanium hull provided strength for deep diving. It also offered a reduced weight advantage leading to higher power to weight ratios resulting in higher accelerations. The higher speed could also be related to some unique propulsion system. The high speeds of Russian attack submarines were meant to counter the advanced propeller cavitation and pump vibration reduction technologies in the USA designs providing them with silent and stealth hiding and maneuvering. Fig. 8. The Nuclear Powered Russian VICTOR I class Attack Submarine Weinberger 1981 . The Alfa Class of Russian submarines used a lead and bismuth alloy cooled fast reactors. They suffered corrosion on the reactor components and activation through the formation of the highly toxic Po210 isotope. Refueling needed a steam supply to keep the liquid metal molten above 257 oF. Advantages were a high cycle efficiency and that the core can be allowed to cool into a solid mass with the lead providing adequate radiation shielding. This class of submarines has been decommissioned. 15. Seawolf class submarines The Seawolf class of submarines provided stealth endurance and agility and are the most heavily armed fast attack submarines in the world. They provided the USA Navy with undersea weapons platforms that could operate in any scenario against any threat with mission .
