On the Formulation of a Pressure-Based Multiphase Compressible-Incompressible Flow Solver

ReFRESCO (www.refresco.org) is a flow solver developed with maritime applications in mind. Therefore, in its original formulation, single and multiphase fluids are assumed to be incompressible (Klaij et al., 2018). However, there are applications, such as slamming or sloshing, where compressibility effects need to be modelled. The first step to include compressibility effects in ReFRESCO was to implement and test a singlephase pressure-based compressible solver (Muralha et al., 2020). Having verified and tested the singlephase compressible solver, the development moved on to the multiphase solver.
Before moving to more demanding test cases, the solver was tested using two cases: horizontal and vertical one-dimensional movement of a liquid piston. These test cases allow to access the solver capabilities to handle compression and expansion of the compressible mixture phase. The vertical liquid piston results were compared to those obtained by Gatin et al. (2020).