Additive Manufactured, High Temperature Micro-gas Turbine Combustor

Lead Research Organisation: University of Bath
Department Name: Mechanical Engineering


Research into the feasibility of an additive-manufactured ultra high efficiency, high temperature micro gas turbine.
The project aims to carry out fundamental research into a highly novel micro gas turbine by designing, manufacturing and testing a combustion system with industry support from HiETA Technologies utilising Additive Manufacturing to create high efficiency cooling systems. The objective is to prove the feasibility of running a system at very high gas temperatures to yield efficiency improvements.

To start, research will be conducted on already existing combustor designs for similar micro-gas turbine applications, to gain an understanding of the already existing technology in the market and identify possible improvements that can be implemented with the use of additive manufacturing. This research will then feed into the initial proof of concept design that will then be analysed using CFD, manufactured by the project industrial partner HiETA and tested in the hot gas stand cell at Bath once it is fitted with a high temperature turbine.

Further research on state of the art combustion cooling designs and CFD analysis on fuel delivery and combustion processes will follow, which will lead to multiple designs for a state of the art combustion system, which HiETA will assist in manufacturing. The designs will then be tested at high temperatures in the hot gas stand test cell at Bath again to validate the designs.

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/R512424/1 30/09/2017 31/12/2022
1939655 Studentship EP/R512424/1 30/09/2017 29/09/2021 Adamos Adamou
Description In summary, this research serves as an important and necessary extension of the publicly available knowledge in terms of all the steps required to effectively apply additive manufacturing to high temperature components. This was achieved through a combination of numerical and experimental work. The main achievements include:
• The development of a novel all-in-one conical radial swirler with in-vane fuel injection, capable of single-digit emissions, low pressure losses and a wide range of operating conditions.
• The numerical and experimental investigations into the use of lattice structures for fuel mixing inside swirler vanes.
• The development and testing of additively manufactured augmented backside liner cooling surfaces which were also investigated for a secondary use as fuel premixing surfaces in combination with a radial liner fuel injector.
• The development and testing of an additively manufactured fuel vaporization injector.
Exploitation Route The first area of further study is the development of additively manufactured combustion chambers capable of operating with multiple fuels. This is of great interest to industry since, depending on which sector a MGT is marketed towards, fuel types will vary and fuel flexibility will be valuable. For example, both the aerospace and stationary power markets are heavily investing in hydrogen fuels, due to environmental reasons. This comes with additional challenges since hydrogen requires alternative storage solutions and more precise combustion methods to avoid flashback and unstable combustion. Other examples of alternative fuels in MGTs include synthetic and liquid fuels such as gasoline, diesel, ammonia and biofuels for range-extended hybrid vehicles and remote power units, and aviation fuels for hybrid aeroplanes and UAVs, all of which require adaptations to the combustion chamber for reliable operation. This can certainly be achieved by exploiting additive manufacturing but requires time and effort to develop and test the resulting concepts.

The second area of further study would mainly benefit industry but has potential for some interesting academic projects too. This includes the integration of other additively manufactured components such as turbomachinery, which could include internally cooled turbine wheels, improved air flow paths for both compressor and turbine housings, and improved cooling for the bearings. Also, the integration of an additively manufactured heat exchanger could provide a myriad of benefits and interesting projects, including the use of the heat exchanger as an insulator for the combustion chamber and the use of variable density heat transfer surfaces and walls and multiple exits from the heat exchanger to provide temperature-specific air at various locations around the combustion chamber and turbomachinery to optimise cooling and heating needs.
Sectors Aerospace, Defence and Marine,Education,Energy

Description HiETA Technologies 
Organisation HiETA Technologies Limited
Country United Kingdom 
Sector Private 
PI Contribution The knowledge of how additive manufacturing can improve combustion systems in micro gas turbines
Collaborator Contribution Provided the knowledge of how to design and manufacture parts for AM.
Start Year 2017