Gas Turbines Flashcards
What is CODLAG
Combination of diesel, electric and gas
What does IEP stand for
Interagated electric propulsion
Gas turbine advantages
- An ability to get underway quickly
- Ease of operational witch the emphasis on remote control
- High power rate ratio
- Minimum ship-borne maintenance
- Low man power requirment
Name all the different parts to a Gas turbine air intake system
- Air intake 3 stage filtration system
- intake trunking
- stone guard
- splitter/silencer
- transmission duct
- Cascade bend
- engine intake flare
What is the process of a air intake 3 stage cycle?
Air enters the 1st stage of the filter system where the air changes direction due to the baffle plates. This change of direction causes water held in suspention to drop out.
After the first stage they the air passes through a knitmesh filter where any particles of mater is removed.
The final stage of water seperation ensures that all the residual water is removed, now the air is completly water free.
What is the purpose of the splitter/silencer?
The purpose of the splitter/silencer is to remove any turbulence, air noise and buffeting.
What is the purpose of the stone guard?
The stone guard prevents large particles of debris from entering the gas turbine when maintenance is being carried out.
What is the purpose of the transition duct?
To change the square cross section to a circle cross section flow.
What is the function of a gas turbine on board?
A gas turbine converts heat energy into rotary motion for ships propulsion
What is the purpose of the engine intake flare?
Seals the engine from the rest of the mudule and houses the water wash rings
Gas turbine cycle
Induction
Compression
Combustion
Power exhaust
Combustion process consists of 3 main parts what are they and their pecentages?
Primary air- 15%
Secondary air-10%
Tertiary air-75%
What does primary air do?
Helps to atomise fuel and prodice air for initial combustion
What is secondary air used to do?
It is used to ensure complete combustion of the fuel and provides a layer of air between the fuel and the flame
Purpose of tertiary air?
After cooling the combustion can the tertiary air is heated by the combustion process causing a rise in pressure and becomes the working fluid.
