Towards analytical solutions of the alloy solidification problem
  In this paper, an analytical solution of alloy solidification problem is presented. We develop a special method to obtain an exact analytical solution for mushy zone problem. The main key of this method is a requirement that thermal diffusivity in the mushy zone to be constant. From such condition we obtain an ordinary differential equation for liquid fraction function. Thus the method can be examine as ''a model'' to achive analytical solution of some unrealistic problems.   An example of solutions is presented: the noneutectic titanium-based alloy solidification. We provide the comparison of numerical simulation results with obtained exact solutions. It shown that very simple apparent capacity-based numerical scheme is provided a good agreement with exact positions of the solidus and liquidus isoterms, and with temperature profiles also.   Finally, some extensions of the method are outlined. 
E.N. Kondrashov