These will decrease the propulsion efficiency and increase fuel consumption.

船舶污底引起阻力增加，降低了船舶的推进效率，增加了耗油量。

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The boss vortex cavitation of propeller can be avoided by PBCF, and an increase of 2% in propulsion efficiency has been measured in the model tests.

桨毂帽鳍可改善毂涡空泡，模型试验状态下可提高推进效率2%左右。

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Propulsion is made of two high performance diesel engines, to provide power and fuel efficiency.

推进由两个高性能柴油发动机，提供电力和燃油效率。

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It has a crew of 20 plus 24 scientists, and features a special hull that diverts bubbles that interfere with sonar operations, and a high-efficiency diesel-electric propulsion system.

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Conventional hybrids use mainly the gasoline engine for propulsion, drawing on the electric drive and batteries only occasionally to (impressively) improve gasoline efficiency.

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