An object oriented implementation of a front tracking finite element method for directional solidification processes

Abstract

This paper focuses on the numerical simulation of phase‐change processes using a moving finite element technique. In particular, directional solidification and melting processes for pure materials and binary alloys are studied. The melt is modelled as a Boussinesq fluid and the transient Navier–Stokes equations are solved simultaneously with the transient heat and mass transport equations as well as the Stefan condition. The various streamline‐upwind/Petrov–Galerkin‐based FEM simulators developed for the heat, flow and mass transport subproblems are reviewed. The use of classes, virtual functions and smart pointers to represent and link the particular simulators in order to model a phase change process is discussed. The freezing front is modelled using a spline interpolation, while the mesh motion is defined from the freezing front motion using a transfinite mapping technique. Various two‐ and three‐dimensional numerical tests are analysed and discussed to demonstrate the efficiency of the proposed techniques. Copyright © 1999 John Wiley & Sons, Ltd.

Development of failure evaluation method for BWR Lower head in severe accident; - Creep damage evaluation based on thermal-hydraulics and structural analyses -

“…Figure 6 represents a comparison in temperature distribution between analysis and experiment. Temperature distribution is represented by normalizing as ̂ = (T-T 1 ) / (T 2 -T 1 ) (where T 1 and T 2 are 302.93 and 311.45, respectively) in order to compare the analysis results to previous one (Sampath, 1999). Temperature distribution obtained from FINAS/CFD agreed well with previous analysis result.…”

“…To confirm the applicability of FINAS/CFD to analysis of melting behavior of metals, we compared the analysis results to previous one (Sampath, 1999). The material used in this analysis is Gallium which melting point is 29.…”

Resolving the Controversy Over Tin and Gallium Melting in a Rectangular Cavity Heated From the Side

“…Most earlier studies of gallium and tin melting were done with coarse grids, due to the limitations of computer capabilities. Many authors [17,28,30] actually acknowledged that their choice of grid size was a compromise between numerical accuracy and cost of computations. Even on the computers of today, the simulations are highly demanding in CPU time, due to the multiscale nature of the problem.…”

“…Several distinct configurations have actually been considered. Cavity aspect ratio values Ar ¼ 1 [6,[10][11][12][13], Ar ¼ 0.714 (the most common) [2,3,6,7,14,16,[18][19][20][22][23][24][25][26][27], Ar ¼ 0.5 [4,6,7,9,15,17,21,24,[27][28][29], and Ar ¼ 0.286 [24,26,27] [30] and numerical [5,23,[30][31][32][33] results are available. Most studies for tin melting have focused on the configuration with Ar ¼ 0.75, Ra=1.2 Â 10 5 , St ¼ 0.0085, and Pr ¼ 0.016.…”

Thermo-Hydro-Mechanical-Chemical Processes in Porous Media

“…One of the first applications of the object-oriented paradigm to finite element analysis was published in 1990 [64], where essential components of finite element methods such as elements, nodes and materials were abstracted into classes. Moreover, the applications to many different physical problems have been investigated, such as linear stress analysis [67][68][69], hypersonic shock waves [72], structural dynamics [73], 2D Mises plasticity [74], linear static problems [75,76], electro-magnetics [77], solidification process [78], heat transfer as well as topological buildup [79]. Moreover, the applications to many different physical problems have been investigated, such as linear stress analysis [67][68][69], hypersonic shock waves [72], structural dynamics [73], 2D Mises plasticity [74], linear static problems [75,76], electro-magnetics [77], solidification process [78], heat transfer as well as topological buildup [79].…”