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arXiv · 2003.05248

Three-dimensional needle network model for dendritic growth with fluid flow

Thomas Isensee·Damien Tourret
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Abstract

We present a first implementation of the Dendritic Needle Network (DNN) model for dendritic crystal growth in three dimensions including convective transport in the melt. The numerical solving of the Navier-Stokes equations is performed with finite differences and is validated by comparison with a classical benchmark in fluid mechanics for unsteady flow. We compute the growth behavior of a single equiaxed crystal under a forced convective flow. As expected, the resulting dendrite morphology differs strongly from the case of the purely diffusive regime and from similar two-dimensional simulations. The resulting computationally efficient simulations open the way to studying mechanisms of microstructure selection in presence of fluid flow, using realistic alloys and process parameters.

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Thomas Isensee, Damien Tourret. 2020-03-11. Three-dimensional needle network model for dendritic growth with fluid flow. https://doi.org/10.1088/1757-899x/861/1/012049

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