Multiphase flows occur in industrial applications such as sealing rings in internal combustion engines, electrolysis, foam casting, and many others. Simulation of these processes is a valuable tool to investigate relevant physical phenomena and perform design optimization in early stages of component development. This is true especially when building multiple prototypes or test rig setups is more expensive than multiple simulations. Cases where the phases do not mix simplify simulation problems within each phases’ domain, but introduce new challenges at the interface between the phases, such as discontinuities in material properties or even changes in material models. The latter case can be observed in the multiphase flow of incompressible and compressible phases [1]. The level-set method has been used to capture the interface motion, providing accurate information on the exact interface location and curvature even for large deformations. Still, resolving the interface accurately requires a high density of degrees of freedom to represent steep gradients in physical fields accurately. Adaptive refinement can reduce computational effort for regions away from the interface, but still relevant to the problem [2]. We investigate adaptive refinement for multiphase flow with the level-set method using space-time finite elements [3]. Both the accuracy and potential gains in performance are investigated for benchmark problems. REFERENCES [1] A. Murrone and H. Guillard. A five equation reduced model for compressible two phase flow problems. Journal of Computational Physics, 202(2): 664-698, 2005. [2] S. El Aouad and A. Larcher and E. Hachem, Anisotropic adaptive body-fitted meshes for CFD. Computer Methods in Applied Mechanics and Engineering, 400: 115562, 2022. [3] M. von Danwitz and V. Karyofylli and N. Hosters and M. Behr, Simplex space- time meshes in compressible flow simulations. International Journal for Numerical Methods in Fluids, 91(1):29-48, 2019.