Complex dynamics of multi-solid systems

Building on previous work (Essmann et al, 2020) exploring the complex dynamics of a single immersed ellipsoid, we investigate the dynamics of multiple immersed ellipsoids under both inviscid and viscous environments. (Earlier, we showed that a single body can present chaotic motions even under viscous environments under certain conditions due to vortex shedding.) We use our in-house GISS solver (https://github.com/eessmann/GISS, Essmann et al 2020) that augments Gerris (Popinet, 2006) with a fully-coupled solver for fluid-solid interaction with 6 degrees-of-freedom (6DOF). We present developments of a new multi-solid solver with extensive parallelisation using the MOOSE framework (https://mooseframework.inl.gov/). In inviscid conditions, we extend Kirchoff’s equations to multiple bodies, using Lamb (1932) as a starting point. Using recurrence quantification and cross-correlation analyses (Marwan et al, 2007), we characterise chaos.