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Combined diesel or gas

Compression-ignition engine plus turbine connected to one drive shaft

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Combined diesel or gas (CODOG) is a type of propulsion system for ships that need a maximum speed that is considerably faster than their cruise speed, particularly warships like modern frigates or corvettes.

01System

For every propeller shaft there is one diesel engine for cruising speed and one geared gas turbine for high speed dashes. Both are connected to the shaft with clutches; only one system is driving the ship, in contrast to combined diesel and gas (CODAG) systems that can use the combined power output of both. The advantage of CODOG is a simpler gearing compared to CODAG, but it needs either more powerful or additional gas turbines to achieve the same maximum power output. The disadvantage of CODOG is that the fuel consumption at high speed is poor compared to CODAG.

02CODOG vessels

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This article is adapted from the Wikipedia article Combined diesel or gas, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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