Understanding how a volume of fluid can undergo a topological change and break into a number of pieces – forming liquid drops or gas bubbles is of interest from both a practical and a fundamental perspective. From a theoretical viewpoint, such problems are multiscale and singular, making computation a challenge.
Breakup of liquid volumes
It is well known that similarity solutions can be deployed to understand the final stages of breakup, however, the approach to these solutions and their limits of applicability are not as well understood. In [Li & Sprittles, 2016], we used computational models to probe these dynamics by considering the breakup of a liquid bridge, see below.
Remarkably, we found that the approach to the ‘universal’ similarity solution proposed in [Eggers 1993] is far more complex than previously expected. As previously observed in [Castrejón-Pita et al 2015], the breakup can transiently pass through a number of regimes, but we also found that the approach to the universal solution is oscillatory, as recently observed experimentally in [Lagarde et al 2018].
Formation of bubbles
In [Simmons et al, 2015] we have developed a computational model for the creation of gas bubbles from a submerged orifice and investigated the dependence of quantities of interest, e.g. bubble volume, on control parameters such as flow rate.