Melt-flflow evolution of d = 260 mm TC4 round ingot (a) on the vertical section in a shallow ‘‘V’’ shape molten pool, (b) presents in 3D with a shallow ‘‘V’’ shape molten pool, (c) on the vertical section in a modifified ‘‘V’’ shape molten pool, (d) presents in 3D with a modifified ‘‘V’’ shape molten pool, (e) on the vertical section in a ‘‘V’’ shape molten pool which is partial to inlet, and (f) presents in 3D with a ‘‘V’’ shape molten pool which is partial to inlet.