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Designing more efficient power gas turbines

Our partnership with Siemens has produced new engine components and tools for faster technology generation.

Professor Gary Lock with a gas turbine
More efficient engines and testing methods mean huge environmental and economic savings.
‘Our relationship with Siemens goes back to 1990. By integrating experimental, modelling and computational skills, we've helped accelerate technology and competitiveness in the power generation industry.’
Gary Lock Professor of Aerospace Engineering

With over 350,000 employees worldwide and 20% of the world's power generated through its products, Siemens is quite literally a global innovation powerhouse. Within its vast product range that includes smart infrastructure, healthcare and renewables, gas turbines form the backbone of Siemens's ongoing energy transition to low-carbon and eventually zero-carbon power generators.

Pursuing engine thermal efficiency

A gas turbine is a combustion engine containing a rotating gas compressor, and a combustor connected by a shaft to a turbine.

Air is drawn into the compressor, then pressurised and heated by injecting fuel into the combustion chamber. This pressurised, high-temperature gas stream expands within the turbine, rotating the shaft which drives the compressor.

At this point, mechanical energy is then translated into electrical energy to power aircraft, trains, ships and electrical generators straight to our homes.

Some energy is lost during this process. As a leading experimental researcher in gas turbine internal air systems and sealing technology, we set out to better understand the governing flow and heat transfer within these power generators. More efficient gas turbines mean a lower carbon footprint and a step closer to Siemens ultimate goal of zero emissions.

Gas turbine rim seals

Airflow can be lost between the rotor discs of a turbine. By improving the seal design we can increase engine efficiency.

New rim seal components

Our research using concept generation, computational fluid dynamics, rig data at technology readiness level, and conceptual validation has helped to develop new rim-seal components to improve engine thermal efficiency. These new components are incorporated into the most advanced Siemens large gas turbines: the 9000HLs.

The 9000HL class is at large scale (305,000 kg) with a power output of 405 megawatts. It features super-efficient internal cooling features for blades or vanes and an advanced combustion system to increase firing temperature. The result is a combined cycle efficiency beyond 63% and a lifespan of 20 to 40 years. Components designed and tested at Bath are forward compatible with hydrogen fuel.

Faster technology with 3D design methods

A CAD image of the Siemens 9000HL
The Siemens SGT6-9000HL is pushing efficiency to the next level. Image from Siemens - see footnote.

Through a Knowledge Transfer Partnership, our rig data and theoretical models have been translated into practical design tools at Siemens. The tools provide accurate predictions of component temperature and life, which reduces the need for expensive engine tests.

Using our experiments we lowered the testing time for two 9000HL prototype engines by 30 days, saving hundreds of thousands of pounds a day. With less reliance on experimental testing, we can reduce development costs and get technology to the market faster.

‘Small gains in efficiency are very important in the drive for cleaner, greener energy. Our close working relationship with the team at Bath, has directly accelerated our technology readiness level.’
Roger Wells Head of Future Technologies at Siemens Lincoln

Conducting gas turbine lab tests

Operational gas turbines are hot, pressured and have high rotational speeds making it difficult to take precise measurements. In our test labs, we model the problem with scaled-down flows and rotational speeds.

Find out more about our research activities

Mechanical engineering research