Combined gas and gas

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Principle of a COGAG propulsion system COGAG-diagram.png
Principle of a COGAG propulsion system

Combined gas turbine and gas turbine (COGAG) is a type of propulsion system for ships using two gas turbines connected to a single propeller shaft. A gearbox and clutches allow either of the turbines to drive the shaft or both of them combined. Marine usage of COGAG systems are similar to those found ashore. [1]

Contents

Description

Combined
marine
propulsion

CODOG
CODAG
CODLAD
CODLAG
CODAD
COSAG
COGOG
COGAG
COGAS
CONAS
IEP or IFEP

A COGAG system consists of two gas turbines, each connected to a reduction gearbox. These are each attached to a coupling with both connected to larger gearbox and then to the ship's propeller. [2]

Advantages and disadvantages

Advantages of the system include a large degree of automation along with quick startup time, they are easier to silence and protect from shock. [3] Compared to combined diesel and gas (CODAG) or combined diesel or gas (CODOG), COGAG systems have a smaller footprint but a much lower fuel efficiency at cruise speed and for CODAG systems it is also somewhat lower for high speed dashes. [4] Issues with COGAG systems include their complexity and gearbox issues and high fuel use. [5]

List of COGAG ships

Citations

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References