Aviation Fuel

Gas Turbine Engines
Aviation Fuel

 

Types of  Aviation Fuel

The fuel used in Gas turbine engine is called the Jet fuel or simply Aviation Turbine Fuel. In 1950s, when commercial jet Industry was developing, Kerosine type fuel was chosen as it showed the best properties. Following are the three types of Fuels used in the aviation industry.

1. Jet A
2. Jet A-1
3. Jet B

Jet A is used in the United States while rest of the world uses Jet A-1. The important
difference between the two fuels is that Jet A-1 has a lower maximum freezing point of -47°C than Jet A fuel having  freezing point of –40°C. Jet A-1 also contains mandatory anti-static additives. The lower freezing point makes Jet A-1 more suitable for long international flights, especially on polar routes during the winter. Jet B fuel is used in some industry in Alaska and Canada as this type of fuel is best suited in cold weathers.

Fuel Performance Properties

Since the primary function of aviation turbine fuel (jet fuel) is to power an aircraft, energy
content and combustion quality are key fuel performance properties. Other significant performance
properties are stability, lubricity, fluidity, volatility, non-corrosivity, and cleanliness. Besides
providing a source of energy, fuel is also used as a hydraulic fluid in engine control systems and
as a coolant for certain fuel system components.

Fuel Octane Number

The Octane number or Octane rating of fuel refers to the ability of  fuel to withstand compression. The fuel which is rated as High Octane will withstand more compression before exploding. The principal difference between piston and jet engines is that combustion is intermittent in a piston engine and continuous in a jet engine. As a result, the engines have different fuel combustion quality requirements. In piston engines, combustion timing is critical to good performance. When combustion is continuous as in Jet Engines, combustion timing is no longer important. If we use low octane fuel in piston Engine, the fuel will burn too quickly and it won't run properly. 

This is why we use Low Octane fuel in Gas Turbine Engines but High Octane Fuel in Piston Engines.


 

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