Project Description
A fully funded PhD opportunity to participate in the world-leading research undertaken by the EPSRC Doctoral Landscape Award at the University of Sheffield.
Supervised by Prof Guang-Jin Li and Dr Jonathan Davidson.
The University of Sheffield is one of the leading Russell Group universities in the UK. We carry out cutting-edge research with strong links to industry. When you enrol to do a PhD with us, you will be working with world-leading academics and have access to top of the range facilities. As a PhD student you will have the opportunity to gain skills not only to conduct research, but also to take your career to the next level, whether you want to stay in academia, go into industry or the public sector, or set up your own company. You will have access to a range of training and support services to help you excel in your studies and beyond.
Project Description
Electrical machines are everywhere, converting energy from one form to another. One particular type, linear machines, produces motion or power in a straight line instead of rotation. These machines can be used in small devices that capture and convert everyday human movement-such as walking or running-into electricity. This electricity can power wearable electronics, health monitoring sensors, or emergency communication devices, reducing the need for frequent battery charging or replacement.
The challenge with existing energy harvesters is that they often have low efficiency, limited durability, and require moving mechanical parts that wear out over time. This makes them less attractive for applications where reliability and portability are essential, such as medical devices or personal electronics.
Our project introduces an innovative solution: using ferrofluids inside the machine’s airgap. A ferrofluid is a liquid containing magnetic nanoparticles that respond strongly to magnetic fields. Unlike ordinary fluids, ferrofluids has higher relative permeability, and hence can enhance the airgap flux density within the machine.
By filling the airgap with ferrofluid, two major benefits are achieved:
1. Improved energy conversion: The ferrofluid helps strengthen the machine’s magnetic field, leading to more efficient electricity generation.
2. Reduced mechanical wear: The fluid cushions moving parts, providing natural damping and lubrication, which increases durability and extends the machine’s lifetime.
Another advantage is that ferrofluids respond dynamically to changes in the environment. As the machine is subjected to varying forces from human motion, the ferrofluid reshapes itself to maintain effective operation. This property makes the design more robust and adaptable compared to traditional rigid structures.
The project combines advanced computer modelling, material science, and machine prototyping. The student will first design and simulate different linear machine configurations with ferrofluid-filled airgaps, testing how the ferrofluid interacts with magnetic fields. Then, selected prototypes will be built and tested under conditions simulating human walking and running.
If successful, this work could lead to compact, maintenance-free energy harvesters capable of powering wearable health monitors, smart textiles, or rescue devices that work anywhere without relying on frequent charging. Beyond consumer electronics, the research could also contribute to self-powered sensors in remote areas, supporting sustainability and reducing dependence on disposable batteries.
In summary, the project aims to create a new generation of ferrofluid-enhanced energy harvesters that are efficient, reliable, and suitable for real-world applications. By harnessing the power of human motion, these devices could play a key role in making portable technologies more sustainable.
Funding Information
Funding Notes
The award will fund the full tuition fee and a maintenance stipend at the UKRI rate (currently £21,805 per annum) for 3.5 years, as well as a research grant to support costs associated with the project.
Eligibility Requirements
The majority of our DLA studentships will be allocated to candidates who qualify for Home fee status, in accordance with EPSRC funding regulations which place strict limits on international recruitment.
Application Process
How to apply
Interested candidates are strongly encouraged to contact the project supervisors to discuss your interest in and suitability for the project prior to submitting your application.
Please refer to the EPSRC DLA webpage for detailed information about the EPSRC DLA and how to apply. Applicants must ensure that they use the correct application form linked to the EPSRC DLA webpage and must submit an application for October 2027 entry. The form is unique to the EPSRC DLA. It contains the list of advertised projects from which to select, and three questions specific to the DLA.
The application deadline is 17:00 GMT 13 January 2027.
