The aeroderivative gas turbine is a lighter weight variation of a gas turbine. Despite being classified as a gas turbine, the fuel source for the aeroderivative turbine is not really gas. Actually, they are designed so that fuel and air are mixed and then ignited to achieve the desired output. The design of gas turbines is comprised of a compression device to facilitate the taking in of air and compressing it (the “gas” in this case) and then applying heat by means of a burner. The resulting flow of hot air is used as the source of powering the turbine. Today, these are typically designed to make use of a combustion process that is continuous as opposed to the intermittent nature of automotive combustion engines. Gas turbines have a long history of use with successful commercial applications since the late 1930’s.
From an engineering perspective, the design of the gas turbine is less complicated than the more commonplace piston engine. These units have essentially one moving part, however, the complexity is in the high degree of exactness required in the manufacturing and the materials used in their construction. Also, some of today’s designs will employ multiple shafts as well as hundreds of blades.
Gas Turbine Applications
One area of widespread use of aeroderivative gas turbine technology is in aviation where the power harnessed by the turbine is used to power a compressor. The hot air that exits the turbine is used for thrust by forcing the air into the atmosphere via an exhaust nozzle.
Gas turbines that are not being used in aircraft or other aviation related devices use some of their power to source the compression device. The power that is left goes to drive an energy conversion device, which could be a generator or perhaps a propeller on a vessel. Turbines that are used for generating electrical power can be small enough to be mounted on trucks for mobile implementations or enormous projects that require months to build.
Aeroderivative gas turbines usually weigh considerably less than those designed for land use. The heavier industrial models designed for land use are referred to as “frame” machines. These days the aeroderivative models are becoming more popular for use in electrical power applications though more for peak and intermittent purposes rather than base power generation.
Advantages of gas turbines
- The capability of supplying relatively large amounts of power given their size
- A long life and low maintenance
- Can be brought online to peak production levels in minutes
- Can be sourced by a wide range of fuels
- No coolant is required since air is the working fluid