Turbine

:For the developers of Massively Multiplayer Online Role Playing Games, see Turbine Inc..

Types of turbines

• Steam turbine
• Gas turbine engines are sometimes referred to as turbine engines. Such engines usually feature a compressor, combustor, nozzle, etc, in addition to one or more turbines.
• high pressure turbine

In a multi-shaft gas turbine, the first turbine downstream of the combustor is usually called the high pressure (i.e. HP) turbine. Normally the HPT is a one or 2 stage unit, the latter usually being more efficient.

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• intermediate pressure turbine

In 3 shaft gas turbine engines, (e.g. Rolls-Royce Trent), the middle unit in the turbine expansion system is often called the intermediate pressure (i.e. IP) turbine. The IPT is usually a single stage unit (i.e. a single row of stators, followed by a row of rotor blades).

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• low pressure turbine

In a multi-shaft gas turbine, the last unit in the turbine expansion system, is usually called the low pressure (i.e. LP) turbine. Number of stages in an LPT can range from one to 7, or even more, depending on the load imposed.

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• power turbine

In turboprop and turboshaft engines, the LP turbine is often called the power turbine

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• transonic turbine

In most of the turbines employed in gas turbine engines, the flow exiting the nozzle guide vanes (NGV's) is at a high subsonic Mach number (e.g. 0.85). In a transonic turbine, the flow exits the NGV's at supersonic velocity, increasing the work capacity of the unit, albeit with a penalty on efficiency.

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• statorless turbine

Most turbines have a set of stators or NGV's to direct the gas onto the turbine rotor blades. In a statorless turbine,(e.g. GE YF120 variable cycle engine) the exit swirl in the gasflow from a preceding turbine rotor is directed onto another contra-rotating rotor stage, situated immediately downstream. The work capacity of the statorless unit is, however, somewhat lower than normal.

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• rotating stator turbine

Usually, being 'earthed' to the engine frame, the stators of a turbine are stationary. However, in the GE36 (UDF) propfan demonstrator engine, the 7 stage power turbine drives a set of contra-rotating propfan blades. The turbine rotors drive one set of propfan blades, whilst the 'unearthed' stators drive the other set of blades, in the opposite direction!

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• Water turbine
• Wind turbine

:Water and Wind turbines have a thermodynamic cycle that is part of weather.

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