Marine gas turbines application

Gas turbine used to power aircraft, trains, ships, electrical generators, offshore vessel and even tanks. But here I will introduce about marine gas turbine. All of the basic theory of gas turbine are the same. Depending on used fields, parameters and thermodynamic cycles of gas turbine are variable. Most marine gas turbines are derived from aircraft jet engines (turbo-prop). Marine gas turbines are available only in specific sizes and ratings, unlike a given diesel engine design which can cover a wide power range with different inline and V-cylinder configurations. All marine gas turbines incorporate the same fundamental components.See pic..

-A compressor to draw in and compress atmospheric air.

-A combustion system into which fuel is injected, mixed with the compressed air, and burned.

-A compressor turbine which absorbs sufficient power from the
hot gases to drive the compressor.

-A power turbine which absorbs the remaining energy in the hot gas stream
and converts it into shaft power.

Lightweight aero-derived -gas turbine designs are favoured for marine propulsion applications. When converting the jet engine into a shaft drive machine it is necessary to provide an additional free power turbine to absorb the energy left in the gas stream and to transmit that energy in the form of shaft power. Special technical and production techniques are applied to the re-designed gas turbine to ensure its suitability for sea level operation at high powers, and for the marine environment. In ship gas turbine installations are especially essential advantages- small specific weight, compactness, a high maneuverability, lower maintenance requirements, virtually no lube oil consumption. Together with these, in the profitability gas turbine installation until concede to diesel installations.

Gradually, significant progress has been made in enhancing the thermal efficiency of simple-cycle gas turbines for ship propulsion over the years. To improve part-load economy and reduce the fuel cost penalty compared with diesel engines. Subsequent advances—design refinements, new materials and cooling techniques, and the appropriate matching of higher compressor pressure ratios—have resulted in some large simple-cycle turbines achieving efficiencies of over 40 per cent. More complex gas turbine cycles can deliver specific fuel consumptions closely approaching the very flat curve characteristics of larger diesel engines. Part-load efficiency can be improved in a number of ways, notably through the intercooled recuperated (ICR) cycle which uses the exhaust gas to heat the combustor inlet. This method was chosen for the WR-21 gas turbine which has achieved a 42 per cent thermal efficiency across 80 per cent of the operating range.

List of latest 3 generations marine gas turbines:
1) LM-6000
2) LM-2500
3) LM-2500+
4) LM-1600
5) LM-2500
6) Marine Spey Rolls-Royce
7) WR-21
8) MT-30
9) MFT-30
10) M75
11) M70
12) M90