This project is one of a number that are in competition for funding from the University of Bath URSA competition , for entry in September 2025.

Early application is encouraged, as excellent candidates may receive an early offer of a funded place before the end of the year. To be eligible for early consideration, you must apply before 24 November 2024.

Project Background:

Joint replacements have been performed in the UK since the 1960s with the first hip implants. Over 250,000 joint replacements are now carried out per year in the UK, with knee and hip replacements accounting for the vast majority of these numbers.

A major issue affecting implant success is wear of the implant surfaces. Wear debris can build up within the joint and cause tissue inflammation and in turn loosening of the implant. Beyond this, there are many other adverse biological responses to wear debris; metallic ions in the lymphatic system, blood and urine of joint replacement patients are linked to lymphadenopathy and necrosis. An analysis of the lubrication mechanisms affecting wear are central to extending the life of joint prostheses.

The lubricating fluid for joints is synovial fluid, which is a complex water-based mixture of proteins, glycoproteins, hyaluronan, phospholipids and cholesterol and patient specific studies have shown that the concentration of macromolecules in synovial fluid can vary significantly. Synovial fluid shows clear shear-thinning behaviour in experiments and the concentration of protein content plays an important role in the rheological properties of synovial fluid. Aggregation of proteins in synovial fluid lubricated joints leads to high viscosity regions and a computational model for this phenomenon has previously been created [1]. This proposed PhD project would use further numerical methods, such as multi-species transport modelling to incorporate shear-breakdown behaviour of protein aggregates [2,3] and multiscale modelling of mixed lubrication regimes [4] to capture more of the underlying physics of synovial fluid lubrication. Parallelisation of code at all stages will also play a large factor in this investigation, as this work will aid in creating a digital twin of ahip implant that can assess performance for prescribed patient needs and enable bespoke optimised prosthetic geometry.

Candidates for this project should have a solid background in fluid mechanics and numerical methods; experience with writing numerical solvers and/or enthusiasm to learn is essential. Candidates should be interested in developing expertise and skills in the fields of non-Newtonian fluids, tribology and High Performance Computing (HPC).

Candidate requirements:

Applicants must have, or be about to obtain, a UK Honours degree 1 ^st or 2.1, or international equivalent.

Non-UK applicants, who are not currently studying in the UK, must meet the programme’s English language requirement before the application deadline – no exceptions will be considered.

Enquiries:

Informal enquiries are encouraged! Direct these to Dr Lee Nissim - [email protected] .

Application Instructions

Please follow the below instructions carefully.

You must make a formal application via the University of Bath’s online application form for a PhD in Mechanical Engineering .

Please note that you can apply for a maximum of two PhD projects on this programme.

In the ‘Funding Your Studies’ section, you must select ‘University of Bath URSA’ from one of the drop-down menus.

In the ‘Your PhD project’ section, you must quote the project title in the PhD project title field, and you must quote the lead supervisor’s name in the field ‘Name of intended supervisor at University of Bath.’

If you are applying for two projects, you must quote the project title for your second choice project in the field ‘Project 2 Title’ and the lead supervisor’s name in ‘Name of intended supervisor for 2 ^nd choice project at University of Bath.

You must ensure that you follow the above steps correctly. Failure to complete these steps will cause errors in the automated processing of your application and may mean that you are not considered for a particular project.

Equality, Diversity and Inclusion

We value a diverse research environment and strive to be an inclusive university, where difference is celebrated and respected. We encourage applications from under-represented groups.

If you have circumstances that you feel we should be aware of that have affected your educational attainment, then please feel free to tell us about it in your application form. The best way to do this is a short paragraph at the end of your personal statement.

The Disability Service ensures that individuals with disabilities are provided the support that they need. If you state if your application that you have a disability, the Disability Service will contact you as part of this process to discuss your needs.

Keywords

Fluid Mechanics, Computational Fluid Dynamics, Rheology, Tribology, Lubrication, Numerical Methods, Prosthetics