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SUMMARYA deforming E'EM (DFEM) analysis of one-dimensional inverse Stefan problems is presented. Specifically, the problem of calculating the position and velocity of the moving interface from the temperature measurements of two or more sensors located inside the solid phase is addressed. Since the interface velocity is Considered to be the primary variable of the problem, the DFEM formulation is found to have many advantages over other traditional front tracking methods. The present inverse formulation is based on a minimization of the error between the calculated and measured temperatures, utilizing future temperature data to calculate current values of the unknown parameters. Also, the use of regularization is found to be useful in obtaining more accurate results, especially when the interface is located far away from the sensors. The method is illustrated with several examples. The effects of the location of the sensors, of the error in the sensor measurements and of several computational parameters were examined.

In this paper finite element modeling of the deformation and stress development in solidifying bodies is presented. Emphasis is given to axially symmetric problems and especially to the accurate implementation of thermal and mechanical phenomena occurring at the freezing front. More specifically, the interface velocity and location are treated as primary variables of the heat transfer analysis, and the isostatic stress condition at the front is utilized as an initial condition in the stress analysis. A hypoelastic-viscoplastic constitutive model and a rate form of the principle of virtual work are involved to model the stresses and deformation. The mechanical and thermal properties are allowed to vary with temperature and strain rate in a realistic manner. Several examples of calculated residual stresses are shown for pure aluminum under axially symmetric geometries and realistic boundary conditions. The effects on the evolving deformations and stresses of the melt pressure, geometry, and cooling conditions are examined and reported.

SUMMARYA new moving/deforming FEM analysis of two-dimensional phase change problems is presented. The region occupied by the solid phase is divided into a non-moving element region and a moving region consisting of the finite elements next to the freezing interface. A transfinite mapping method is used to generate new finite-element meshes and motion in the liquid phase during simulations. Several twodimensional Stefan problems are analysed and discussed in relation to analytical solutions and other numerical techniques.