Parallel computation of single-needle dendrites in 3D and comparison with microgravity experiment

The dendritic growth of a single needle dendrite is studied in three dimensional space by using a phase field model and parallel architecture. A large difference in the length scales (capillarity length, the tip radius of the interface and etc.) poses difficulty in the computation of dendritic growth. For succinonitrile (SCN), the difference in the length scales is as high as 10(-8) cm to 1 cm. Consequently, a grid of 5003 is used on the supercomputer to resolve these length scales. The parameters, initial and boundary conditions are identical to those of the microgravity experiments for succinonitrile (SCN). The numerical results are (i) consistent with the experiments; (ii) compatible with the experimental conclusion that tip velocity does not increase with increased anisotropy; (iii) different for 3D versus 2D by a factor of approximately 1.9; (iv) essentially identical for fully 3D versus rotationally symmetric 3D.