The Meshfree Interface Finite Element Method for Numerical Simulation of Dendritic Solidification with Fluid Flow

摘要

In this paper, we use the newly proposed meshfree interface finite element method (MIFEM) for numerical simulation of dendritic solidification with fluid flow. In the MIFEM, meshfree points without connectivity are imposed directly at the zero-isocontour of an implicit function defining the interface which is allowed to arbitrarily intersect the finite elements. The MIFEM utilizes the constructed interface points for meshfree solution of a variational level set equation based on the Ginzburg-Landau energy functional minimization such that the reinitialization procedure is completely eliminated. To account for inter-element discontinuities, field variables at interface-embedded elements are computed by extending the approximation using the meshfree interface points as additional degrees of freedom directly corresponding to the interface. This is achieved by meshfree interpolation at the interface region via radial basis functions which inherently satisfies the Kronecker-delta and the partition of unity conditions allowing for precise and easy imposition of Dirichlet boundary conditions at the interface. We use the MIFEM for solving the interfacial evolution equation and the set of mass, momentum, and energy conservation equations describing the dendritic solidification process with fluid flow. Mathematical formulation and implementation to multiple case studies will be presented and discussed.