Phase-field simulation dendritic growth under forced convection with hypergravity

【摘要】 The phase-field method is used to study the free dendritic crystal growth under forced convection with hypergravity,the hypergravity term is introduced into the liquid-phase momentum equation to examine the dendritic growth. The paper focuses on the morphology of dendrite growth as well as the tip radius of the upstream dendritic arm and the average growth velocity of dendrite tips under different hypergravity levels. The results show that the morphology of dendrite changes significantly under represent simulation conditions when the hypergravity reaches 35g0, the upstream dendritic arm will bifurcate and the horizontal dendrite arms gradually tilt upwards. This change is mainly caused by the hypergravity and flow changing the temperature field near the dendrite interface. In addition, before the morphology of the dendrite is significantly altered, the radius of the tip of the dendrite upstream arm becomes larger with the increase in hypergravity, and the average growth velocity will increase linearly with it. The morphology of dendritic growth under different hypergravity and the changes in the tip radius along with the average growth velocity of the upstream dendritic tip with hypergravity are given in this paper. Finally, the reasons for these phenomena are analyzed.更多还原

【Abstract】 The phase-field method is used to study the free dendritic crystal growth under forced convection with hypergravity,the hypergravity term is introduced into the liquid-phase momentum equation to examine the dendritic growth. The paper focuses on the morphology of dendrite growth as well as the tip radius of the upstream dendritic arm and the average growth velocity of dendrite tips under different hypergravity levels. The results show that the morphology of dendrite changes significantly under represent simulation conditions when the hypergravity reaches 35g0, the upstream dendritic arm will bifurcate and the horizontal dendrite arms gradually tilt upwards. This change is mainly caused by the hypergravity and flow changing the temperature field near the dendrite interface. In addition, before the morphology of the dendrite is significantly altered, the radius of the tip of the dendrite upstream arm becomes larger with the increase in hypergravity, and the average growth velocity will increase linearly with it. The morphology of dendritic growth under different hypergravity and the changes in the tip radius along with the average growth velocity of the upstream dendritic tip with hypergravity are given in this paper. Finally, the reasons for these phenomena are analyzed.更多还原