MARE 100 Marine Gas Turbines

when was the first gas turbine invented

1930

who invented the gas turbine

Sir Frank Whittle

What was it first used as

jet aircraft

when did the US begin development and who were awarded teh contracts

started in 1941; GE and  Westinghouse were the companies awarded contracts

when did MArine Gas Turbines began

1951

What was the first marine gas tanker called

Tanker AURIS

Benefits of a marine gas Turbine

• large power-to-wight ratio

• fuel flexibility

• drastically less vibration than reciprocating engines

• reliability

• system efficiency and flexibility

• combined low and high speed

Detriments of Marine Gas turbines

• high stress engines that require vital attention to detail

• highly complex control systems

• high frequency noise

• F..D in air

• Larger intake/exhaust ducting

5 stages of the Brayton Cycle

1. intake

2. compression

3. combustion

4. expansion

5. exhaust

intake

air enters the inlet at atmospheric pressure and ambient temperature

compression

as the air passes through the compressor, it increases in pressure and temperature and decreases in volume

combustion

occurs at constant pressure while the addition of heat causes a shar p increase in volume

Expansion

gases at a constant pressure and increased volume enter the turbine and expand through it as the gases pass through the turbine rotor, the rotor turns kinetic energy into mechanical energy. The expanding size of the passages causes further increase in volume and a sharp decrease in pressure and temperature

Exhaust

The gases are released through the stack with a large drop in volume and at a constant pressure

what are gas turbines utilized for

high speed operations

three common naval propulsion configurations

• cogag (Combined Gas and Gas)

• codag (combined diesel and gas)

• codog (Combined Gas or Diesel)

cogag (Combined Gas and Gas)

• two or more gas turbines

• either turbine can run alone for cruising

• both can run together for high speed

CODAG (Combined Diesel and Gas)

• uses diesel engines for efficient cruising

• uses gas turbines for high speed

• can operate simultaneously combining their power

CODOG (Combined Diesel Or Gas)

• diesel or gas turbine can run

• both cant run at the same time

• diesel = cruising

• gas turbine = high speed