Multi-Physics and Multi-Scale Meshless Simulation System for Direct-Chill Casting of Aluminium Alloys

Abstract

This paper represents an overview of the elements of the user-friendly simulation system, developed for computational analysis and optimization of the quality and productivity of the electromagnetically direct-chill cast semi-products from aluminium alloys. The system also allows the computational estimation of the design changes of the casting equipment. To achieve this goal, the electromagnetic and the thermofluid process parameters are coupled to the evolution of Lorentz force, temperature, velocity, concentration, strain and stress fields as well as microstructure evolution. This forms a multi-physics and multi-scale problem of great complexity, which has not been demonstrated before. The macroscopic fluid mechanics, solid mechanics, and electromagnetic solution framework is based on local strong-form meshless formulation, involving the radial basis functions and monomials as trial functions, and local collocation or weighted least squares approximation. It is coupled to the micro-scale by incorporating the point automata solution concept. The entire macro-micro solution concept does not require meshing and space integration. The solution procedure can be easily and efficiently automatically adapted in node redistribution and/or refinement sense, which is of utmost importance when coping with fields exhibiting sharp gradients, which occur in the phase-change problems. The simulation system is coded from scratch in modern Fortran. The elements of the experimental validation of the system and the demonstration of its use for round billet casting in IMPOL Aluminium Industry are shown.

Numerical and Experimental Study on the Direct Chill Casting of Large-Scale AA2219 Billets via Annular Coupled Electromagnetic Field

“…Zhang [ 15 ] stimulated the temperature, flow velocity distribution profiles, and the sump depth by coupling the electromagnetic field in the simulation of LFEC. Vanja Hatić [ 18 ] and Božidar Šarler [ 19 ] developed a comprehensive, multiphysics, meshless, unique numerical model to simulate direct chill casting under a LEFC, and the effect of the low-frequency electromagnetic force on the temperature, liquid fraction, and fluid flow are solved with the meshless diffuse approximate method under different current densities and frequencies. Wang [ 20 ] stimulated the solidification characteristic under different phase-pulsed magnetic fields using a transient two-dimensional axisymmetric model and compared the results of the components of the Lorentz force.…”