Fully resolved numerical simulations of fused deposition modeling. Part II – solidification, residual stresses and modeling of the nozzle

摘要

Purpose - This paper continues the development of a comprehensive methodologyfor fully resolved numerical simulations of fusion deposition modeling.Design/methodology/approach - A front-tracking/finite volume method introducedin Part I to simulate the heat transfer and fluid dynamics of the deposition ofa hot polymer filament is extended by adding an improved model for theinjection nozzle, including the shrinkage of the polymer as it cools down, andaccounting for stresses in the solid. Findings - The accuracy and convergenceproperties of the new method are tested by grid refinement and the method isshown to produce convergent solutions for the shape of the filament, thetemperature distribution, the shrinkage and the solid stresses for filamentsdeposited on a fixed bed. Research limitations/implications - The methodpresented in the paper focuses on modeling the fluid flow, the cooling andsolidification, as well as volume changes and residual stresses using arelatively simple viscoelastic constitutive model. More complex material modelsdepending, for example, on the evolution of the configuration tensor, are notincluded. Practical implications - The ability to carry out fully resolvednumerical simulations of the fusion deposition process is expected to becritical for validation mathematical models for the material behavior, helpexplore new deposition strategies, and to provide the "ground truth" for thedevelopment of reduced order models. Originality/value - The paper completesthe development of the first numerical method for fully resolved simulation offusion filament modeling.