Aerospace Tribology
We are a centre of excellence in all aspects of aero-engine abradable lining tribology. The team has pioneered a range of in-situ measurement techniques for characterising wear in this high speed – high force interaction between the blade and liner, investigating the fundamental drivers.
Our research aims to improve the performance of abradable lining systems used in aero-engines to seal between the blade and surrounding casing, as this has a significant impact on the overall efficiency of the engine. Early work focused on characterising the wear mechanisms present in compressor sealing systems, as well as the underlying physical processes taking place, through the use of a range of in-situ measurement techniques. This work has led onto optimisation of sealing systems used for compressors, turbines and shafts, and application to industry in conjunction with Rolls-Royce. The image shows test samples from our high speed rotating rigs, where wear mechanisms present for blade-liner interactions in an aero-engine have been successfully recreated, as well high speed optical and thermal camera images used to characterise adhesive pick up on the blade tip.
Our Expertise and Activities
- We have a range of high speed test rig capable of replicating the interaction between the blade and liner. The equipment allows us to test at blade speeds of up to 300m/s, with one of our rigs also able to heat the blade tips. We use these rigs to explore the wear mechanisms present for a range of different sealing systems.
- We are able to instrument our test rigs with stroboscopic measurements systems, imaging the blade tip on a pass by pass basis. This allows us to determine adhesion and wear rates for the blade tip, as the incursion event progresses. In turn we use a high speed thermal camera to investigate how hot spots on the abradable surface drive this wear mechanic.
- Via load cells mounted underneath the contact we are able to determine cutting forces. This measurement approach, when combined with digital image correlation of the blade-abradable contact, enables the load transfer and material removal mechanism to be investigated, allowing us to investigate how effectively the blade cuts the liner.
- As well as our in-situ measurement techniques, we also apply a range of imaging approaches to characterise samples post-test, investigating the nature of transfer layers, as well as how materials compact and breakdown.
- In addition to investigating fundamental aspects with respect to the wear behaviour of abradable linings, we also work closely with Rolls-Royce. Investigating current aero-engine challenges, as well as exploring next generation sealing systems.
Current and Past Research Projects
- Wear Mechanics and Adhesions of Compressor Blade-Liner Interactions
- Investigation of the Role of Blade Geometry in the Wear of Nickel Based Liners
- Wear Mechanisms in Shaft Fin Seal Liner Systems
- Material Removal by Abrasive Coatings used in Stator Blade Contacts
- Abrasive Tipped Blades for High Temperature Turbine Liner Applications
- Durability of landing gear pin joints and development of maintenance free joints
- Lubrication performance of actuator seals
Contact
Prof Matt Marshall, m.b.marshall@sheffield.ac.uk