MFC: An open-source high-order multi-component, multi-phase, and multi-scale compressible flow solver

Abstract

MFC is an open-source tool for solving multi-component, multi-phase, and bubbly compressible flows. It is capable of efficiently solving a wide range of flows, including droplet atomization, shock–bubble interaction, and bubble dynamics. We present the 5- and 6-equation thermodynamically-consistent diffuse-interface models we use to handle such flows, which are coupled to high-order interface-capturing methods, HLL-type Riemann solvers, and TVD time-integration schemes that are capable of simulating unsteady flows with strong shocks. The numerical methods are implemented in a flexible, modular framework that is amenable to future development. The methods we employ are validated via comparisons to experimental results for shock–bubble, shock–droplet, and shock–water–cylinder interaction problems and verified to be free of spurious oscillations for material-interface advection and gas–liquid Riemann problems. For smooth solutions, such as the advection of an isentropic vortex, the methods are verified to be high-order accurate. Illustrative examples involving shock–bubble–vessel-wall and acoustic–bubble–net interactions are used to demonstrate the full capabilities of MFC. Program summaryProgram title: MFC (Multi-component Flow Code)CPC Library link to program files:http://dx.doi.org/10.17632/8y55zscjd3.1Developer’s repository link: https://mfc-caltech.github.ioLicensing provisions: GNU General Public License 3Programming language: Fortran 90 and PythonNature of problem: Computer simulation of multi-component flows requires careful physical model selection and sophisticated treatment of spatial and temporal derivatives to keep solutions both thermodynamically consistent and free of spurious oscillations. Further, such methods should be high-order accurate for smooth solutions to reduce computational cost and promote sharper interfaces for discontinuous ones. These problems are particularly challenging for flows with material interfaces, which are important in numerous applications.Solution method: The present software incorporates multiple physical models and numerical schemes for treatment of compressible multi-phase and multi-component flows. Additional physical effects and sub-grid models are included, such as an ensemble-averaged bubbly flow model. The architecture was designed to ensure that further development is straightforward.