The focus of lab-on-a-chip technology centers on small, low power devices that can be integrated on a microscopic scale to perform laboratory functions within one unit or “chip”. In order to achieve this, one has to understand how to transfer fluid at this scale. Due to the low Reynolds number limit, such devices need to break time-reversible symmetry to produce a net flow. There has been a degree of interest and research into using magnetic materials to achieve this. In this work, we propose a new model employing ferromagnetic elements for construction of a practical microfluidic pump. The design is based on a repeated chain of magnetic discs connected together via links with hinges at the centers of the discs, which allow the discs to rotate (Fig 1a). While the model is based on that of ferromagnetic swimmers[1]. The device is surrounded by fluid and is activated by an external AC magnetic field. The magnetic and elastic forces in this device can work together against the fluidic forces to create a time-irreversible movement, which results in a net flow. While magnetisation of all the discs are oriented in the same direction, the relative rotational stiffness of the discs (or hinge stiffness) is varied to produce a lag in the response to the magnetic torque. This collective effect is similar to that of a metachronal wave, which is ultimately responsible for the flow. We found that if both discs had the same rotational stiffness, then no flow was produced. Depending on the chosen frequency, there is an optimal rotation stiffness of the two discs where a maximum flow rate is achieved. We observed as the frequency increases so does the flow, until the frequency is too large for the discs to turn to their maximum angle before the direction of the magnetic field reverses. To conclude, we demonstrated that an elasto-magnetic device can produce a net flow at low Reynolds number. The flow direction can be controlled by altering the frequency of the driving magnetic field or by using different rotational stiffness. These results could lead to new types of ferromagnetic pumping devices.References: [1] A. D. Gilbert, et al., Q. J. Mech. Appl. Math., 64, 239 (2011).

Investigation of a Coupled Elasto-Magnetic Discs for Low Reynolds Number Pumps

This session is sponsored by

![](https://assets.underline.io/uploads/markdown_image/1/image/362be088e44a6f002a975b6dcbdad6c4.png)

The GMW Best Poster Award is given to one poster presentation in each Live Q&A Session throughout the Conference week. The Poster Session Chairs nominate the best poster from their poster session, based on the level of the research, quality of the poster, and clarity of the presentation, and then one winner per Live Q&A Session is ultimately selected by the Program Committee Co-Chairs. All winners will be displayed in this Best Poster Award room, thanks to the generous support of GMW.

GMW Best Poster Award Winners

poster

The 65th Annual Conference on Magnetism and Magnetic Materials (MMM 2020) was held in a virtual form. The COVID-19 pandemic, with its associated uncertainty about international travel and the ability to gather in large groups, meant that the Steering Committee decided to cancel the face-to-face meeting that had been planned in Palm Beach, Florida November 2-6, 2020.

We were reluctant to give up the benefits of meeting face-to-face, and know that shifting to a virtual conference is a significant change for this community. Nevertheless, we are first and foremost concerned about the health and safety of all our Conference participants and their loved ones on returning home after travelling.

The MMM 2020 Steering Committee was working exceptionally hard, along with our sponsors, the IEEE Magnetics Society and AIP Publishing, to make this event serve the needs of our participants, who live in time zones all around the globe, in the best possible way. 

You need a ticket to explore this event.

If you have already registered for MMM 2020, and you have already created an account, then you
just need to login (above).

If you have already registered for MMM 2020, but you have not yet created an account, then you
need to click on &quot;create an account&quot; (above) and then login.

Forgot your password? Go to
https://www.underline.io/log-in

If you have not yet registered for MMM 2020 but would like to do so, go to
https://magnetism.org/register

Still need help? Contact our team!


Elizabeth Martin

2

SHORT BIO

Presentations

Investigation of a Coupled Elasto-Magnetic Discs for Low Reynolds Number Pumps

Investigation of a Coupled Elasto-Magnetic Discs for Low Reynolds Number Pumps

Stay up to date with the latest Underline news!

PRESENTATIONS

CONFERENCES

COMPANY

RESOURCES