Study on 3D full cell ledge shape calculation and optimal design criteria by coupled thermo-flow model

Abstract

Based on the finite element method and enthalpy-porosity technique, a coupled thermo-flow model, which could take full account of the effect of melts flow on the heat transfer and ledge formation in the cell, was built. The steady-state 3D full cell ledge shape was accurately achieved according to the model. The effects of electromagnetic force (EMF) distribution and vortex morphology on the ledge thickness were studied. The results show that EMF distribution is the main factor influencing the shape of ledge while the vortex morphology mainly affects the thickness of the ledge in the vortex intersection zone. Based on this, the design criteria of EMF were proposed to improve the uniformity and regularity of ledge, namely lowering the fluctuation of the EMFs along long axis direction of cell, reducing the EMFs absolute value difference between the cell side of upstream and downstream and designing multi-vortex flow pattern.