Gas turbine burner design enhanced with additive manufacturing

German firm Euro-K has enhanced its burners for micro-gas turbines with a design based on metal additive manufacturing (AM). The new design, which avoids the constraints of conventional metal cutting and uneven cooling of castings, is able to burn both gas and liquid fuel equally efficiently, an advance on traditional systems.

The technology is able to produce small batch sizes economically and allows burner assembly costs to be reduced by 20 per cent, according to the company. The size of the combustion chamber can also be reduced by 20 per cent with the AM method.

Whereas the formation of a combustible fuel/air mixture is relatively straightforward with gaseous fuels, liquid fuels present a challenge, as the surface area must be greatly increased. This is generally done by projecting it in a very fine spray using pneumatic, mechanical or pressure differential principles. Consequently, the availability of burners that support the use of liquid as well as gaseous fuels is limited.

To create the optimal burner for use in the micro-gas turbines of one of its customers, a Berlin-based plant builder, the Euro-K project team used an EOS M 290 metal AM system and EOS’s NickelAlloy IN718 material. NickelAlloy IN718 is a heat- and corrosion-resistant material that has excellent tensile strength, resilience, and resistance to creep and fracture at temperatures up to 700°C.

The new burner is able to use gaseous and liquid fuels equally effectively. Optimised geometry also allows the use of liquid fuel oils that are classified as difficult to burn, such as those distilled of alcohol.