Contact Mechanics and Material Removal in Abradable Linings
Lead Research Organisation:
University of Sheffield
Department Name: Mechanical Engineering
Abstract
Abradable linings are used within compressors and turbines as they allow blade tip clearances to be minimised, whilst not suffering the penalty of blade tip wear. They are of particular interest in aero-engines, where they help to improve engine efficiency and minimise the consumption of aviation fuel. This proposal is concerned with investigating cutting type wear experienced by abradable linings, during the incursion of a blade tip into the lining. Previous studies have considered the process to be similar to that of high speed machining, whereas recent observations from engine tests have indicated that debris is in fact ejected from the rear of the contact.In this study a demonstrator platform will be developed for simulating aero-engine compressor rubs, and the associated contact mechanics investigated using an ultrasonic technique in combination with a finite element model. Through this approach, material failure points will be identified, and insight gained as to why debris is ejected from the rear of the contact. Blade tip geometries will also be investigated as part of this study, as well as their effect on material removal. This topic area is particularly pertinent as aero-engine manufacturer's looks to minimise blade tip clearances further inorder to increase engine efficiency, thus increasing the frequency of abrasion events.
Planned Impact
As was highlighted in the Case for Support, research into abradable linings is extremely pertinent as they significantly influence the efficiency of turbo-machinery. Further, as designers currently look to utilise systems for dynamically controlling blade tip clearances, the topic area of micro-rubs becomes particularly important. The novel investigative work in this study directly engages with this issue, and will be of interest to both aero-engine and turbo-machinery manufacturers. Specifically, the topic area of abradable linings in aero-engine compressors has been selected as the research platform, as it is the highest impact area for the topic due to the incursion rates experienced by the linings during flight. It is planned that dissemination will target both senior industrial figures as well as more specific practitioners. This will be performed through technical reporting and presentation at conference events, as well as through focused workshop events for engineers directly involved in the topic. Due to the link with Rolls-Royce, part of the dissemination will take place through Integrated Project Team meetings to in part fulfil the latter requirement. This work also has wider impact with regards to measuring contact pressures from a dynamic contact. The techniques demonstrated here offer the prospect of developing a condition monitoring tool, whereby the evolution of a dynamic contact due to wear can be considered. In light of this, technical seminars and events related to condition monitoring will also be targeted.
People |
ORCID iD |
Matthew Marshall (Principal Investigator) |
Publications
Fois N
(2014)
An investigation of the relationship between wear and contact force for abradable materials
in Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology
Fois N
(2013)
Adhesive transfer in aero-engine abradable linings contact
in Wear
Singleton R
(2014)
Rail grinding for the 21st century - taking a lead from the aerospace industry
in Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit
Stringer J
(2012)
High speed wear testing of an abradable coating
in Wear
Watson M
(2015)
Effects of blade surface treatments in tip-shroud abradable contacts
in Wear
Watson M
(2018)
Wear mechanisms at the blade tip seal interface
in Wear
Description | Outputs used by Rolls-Royce with respect to current engine design and performance (unable to give specific details due to confidentiality agreement). |
First Year Of Impact | 2014 |
Sector | Aerospace, Defence and Marine |
Impact Types | Economic |
Description | Abradable Linings in Aero-Engines - Project Studentship |
Amount | £32,500 (GBP) |
Funding ID | RES 443/953 |
Organisation | Rolls Royce Group Plc |
Sector | Private |
Country | United Kingdom |
Start | 01/2012 |
End | 01/2015 |
Description | Force Measurement of Abradable Lining Blade Strikes |
Amount | £22,496 (GBP) |
Funding ID | R/134121 |
Organisation | Rolls Royce Group Plc |
Sector | Private |
Country | United Kingdom |
Start | 03/2012 |
End | 06/2012 |
Description | Network Rail - High Speed Grinding |
Amount | £150,454 (GBP) |
Funding ID | NR/Sheff/001 |
Organisation | Network Rail Ltd |
Sector | Private |
Country | United Kingdom |
Start | 06/2011 |
End | 12/2015 |
Description | Rolls-Royce - Abrasive Tipping of Compressor Blades |
Amount | £32,500 (GBP) |
Organisation | Rolls Royce Group Plc |
Sector | Private |
Country | United Kingdom |
Start | 09/2013 |
End | 03/2017 |
Description | Rolls-Royce Project Studentship - Metallic Foams |
Amount | £40,000 (GBP) |
Funding ID | X/008917 |
Organisation | Rolls Royce Group Plc |
Sector | Private |
Country | United Kingdom |
Start | 09/2015 |
End | 03/2019 |
Description | Rolls-Royce Research Support |
Amount | £121,638 (GBP) |
Organisation | Rolls Royce Group Plc |
Sector | Private |
Country | United Kingdom |
Start | 01/2014 |
End | 12/2015 |
Description | Rolls-Royce Research Support |
Amount | £55,757 (GBP) |
Organisation | Rolls Royce Group Plc |
Sector | Private |
Country | United Kingdom |
Start | 01/2012 |
End | 01/2015 |
Description | Adhesion of Metallic Foams |
Organisation | University of Sheffield |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Work investigating the functionality of different joining techniques for attaching metallic foams to compressor casings, for use as abradable linings. Specifically collaboration has occurred in testing adhered foams. Testing of adhered metallic foams for use as abradable materials. Research has been on-going (sponsored by Rolls-Royce) in Materials Science and Engineering at the University, and testing work on the functionality of the developed bonding mechanism has been undertaken on the test rig created as part of this grant. |
Collaborator Contribution | Development of metallic foams as abradable materials. |
Impact | Rolls-Royce funded PhD studentship investigating the abradability performance of metallic foams. |
Start Year | 2011 |
Description | Testing of Metallic Foams |
Organisation | National Composites Centre (NCC) |
Country | United Kingdom |
Sector | Private |
PI Contribution | Testing of novel filled metallic foams for use as aero-engine abradable systems, in order to determine wear mechanics. |
Collaborator Contribution | Development of novel foams and filling techniques. |
Impact | Early stage indications of wear mechanics aiding optimisation of generation two materials. |
Start Year | 2015 |
Description | Science in Parliament |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | Yes |
Geographic Reach | National |
Primary Audience | Policymakers/politicians |
Results and Impact | Parliamentary science journal, article highlighting industry linked research case studies from the Leonardo Centre for Tribology. The work on abradable linings, and wear mechanics are ultimately linked to aero-engine efficiency, was one of the central case studies included. |
Year(s) Of Engagement Activity | 2011 |
Description | Sir John Beddington Prize Lecture |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Policymakers/politicians |
Results and Impact | A short research brochure for distribution at a prize lecture by Sir John Beddington, Chief Scientific Advisor to the Government. The brochure highlighted research activity in the Leonardo Centre, and the work on abradable linings was included as a full page case study. This event was attended by upwards of 80 delegates, including amongst others Nick Clegg (Deputy Prime Minister), David Willetts (Minister for Science), Members of the Science and Technology Committee), CEO's of major industrial organisations (Boeing, Ford, Jaguar Land Rover, etc.), Heads of Research Councils, and Embassy Science Attaches. |
Year(s) Of Engagement Activity | 2011 |
Description | World Tribology Congress (Turin) |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Other audiences |
Results and Impact | Presentation at World Tribology Congress Turin detailing new techniques in characterising wear mechanics of abradable materials, this was well received, and the techniques demonstrated have been adopted by a range of other researchers. |
Year(s) Of Engagement Activity | 2013 |