  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 gas bubble
cavitation. 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.
