ParaSiF_CF: A Partitioned Fluid-Structure Interaction Framework for Exascale

A new massively parallel partitioned fluid-structure interaction (FSI) simulation framework, ParaSiF_CF, has been built. This FSI framework employs Code_Saturne to solve the computational fluid dynamics (CFD), FEniCS to solve the computational structure mechanics (CSM) and the Multiscale Universal Interface (MUI) for data exchange. The codes adopted in this framework have demonstrated excellent individual performance in highly parallel simulations [1-3]. The partitioned approach to FSI offers several advantages over a monolithic coupling. The primary advantage motivating the present study is the ability to leverage the highly specialised legacy codes that have had decades invested in them (i.e. Code_Saturne for CFD and FEniCS for CSM), and are tailored to the task they are designed to solve (e.g. consider the wealth of turbulence models in Code_Saturne, which are simply unavailable in FEniCS). Both linear elastic and hyper-elastic structure solvers have been implemented in the framework. The parallel performance of the framework has been optimised and its scalability has been assessed aiming for high parallel efficiency on large problem sizes. Around 85% parallel efficiency has been achieved with high node counts in our tests.