Additive Manufacturing (AM) offers highest production flexibility and almost unlimited freedom of design. While truly predictive computational modeling approaches are highly desirable to foster digital process chains in part design and qualification, the multi-scale nature inherent to most AM technologies makes process simulation very challenging. This minisymposium focuses on recently developed micro- and mesoscale simulation techniques in AM, including experimental model calibration and validation. Computational modeling and simulation approaches for any class of AM processes (e.g., laser power bed fusion, electron beam melting, directed energy deposition, binder jetting, material jetting, fused deposition modeling, stereolithography) and materials (e.g. metals, plastics, ceramics, concrete and their composites as well as biological materials), and also for related processes (e.g., laser or electron beam welding) are welcome. Topics of interest for this minisymposium include (but are not limited to): - Simulation of AM processes at meso- and microscale resolution, resolving individual powder particles, filaments and subcomponents, or crystal structures - Mesoscale prediction of heat transfer, multiphase flow and powder phenomena (powder spreading, melt pool dynamics, melt–vapor–powder interaction, liquid binder flow, filament deposition), surface topology and composition, including defect evolution - Multiphase interface modeling in melt pool / binder simulations using mesh-free (e.g., smoothed particle hydrodynamics), moving grid (e.g., ALE), or fixed grid approaches (level-set, phase-field, immersed boundary, ghost-fluid, XFEM, CutFEM) - High-fidelity energy absorption models (ray tracing) for laser- or electron beam-based AM - Microstructure modeling including phase and grain evolution (e.g., phase-field modeling, cellular automaton modeling), and linking microstructural features (grain size, orientation, phases) to mechanical properties - Adaptive spatial and temporal discretization strategies, non-standard numerical solution schemes and model order reduction approaches allowing for increased computational efficiency - Multi-physics and multi-scale coupling techniques - Physics-based, data-driven, and hybrid approaches - Combined simulation and in-situ monitoring for rapid build qualification A companion minisymposium “Modeling and Simulation of Additive Manufacturing: Part-Scale Approaches” focuses on simulation approaches on part-scale.