ARCHER2 Calendar February 2026

Lattice Boltzmann modelling of droplet equatorial streaming in an electric field

Dr Geng Wang, Department of Mechanical Engineering, University College London

In a strong electric field, when a low-viscosity droplet is placed in a medium with higher electric conductivity and permittivity, it forms a lens-like shape and continuously generates detached liquid rings and fingers at the equator. As these rings and fingers break up, hundreds of size-controllable satellite droplets are produced in the equatorial plane of the mother droplet; this phenomenon is known as equatorial streaming.
This figure shows the morphology of a streaming droplet and the typical evolution process of equatorial streaming, with the droplet coloured by charge density distribution. The results are obtained using a cutting-edge electrohydrodynamic lattice Boltzmann model developed at UCL. The simulations are conducted on the ARCHER2 national supercomputer, and for a typical case, more than 4000 cores are used for over one day.

This image was published on the February page of the ARCHER2 2026 printed calendar.