Efficiency-Enhanced High-Fidelity Simulation Solver for Incompressible Two-Phase Flows and Fluid-Structure Interactions

In fluid dynamics, the interactions of two-phase incompressible flows with structural elements form a pivotal aspect, significantly influencing a variety of applications such as marine ecosystem dynamics, advanced marine vessel design, environmental hazard mitigation, and renewable energy production systems. To address these complex dynamics and interactions, we have devised a high-fidelity computational solver, tailored specifically for the accurate simulation of incompressible two-phase flows and fluid-structure interactions. Our solver employs the incompressible Navier-Stokes equations, with a synergistic implementation of the level set and volume of fluid methods. This combination enables efficient capturing of the complex geometry at the two-fluid interface. An enhanced immersed boundary method is integrated to effectively capture the fluid-structure interactions, minimizing divergence error in the process. We validated this computational tool using several benchmark tests. The transition from our previous Fortran + MPI CPU-based code to a more versatile and adaptable C++ + CUDA GPU-oriented version substantially improved the computational performance. This transition, when supplemented with the systematic optimization of kernel functions and bandwidth management, has culminated in a substantial enhancement in the solver's efficiency, as supported by quantitative comparisons. Moreover, through an in-depth analysis of the various stages in the computational process, we have obtained valuable insights for further optimizations of the solver.