The Asymptotic Analysis Of Temperature And Fluid Field For Crystal Growth In An External Flow

Nucleating and crystal growth are important parts in the process of metal solidification.The main factors that influent the crystal growth includes the mass, momentum and energy inthe system. In a realistic crystal growth system, convection in melt is always unavoidable,therefore, the paper studies the crystal growth with the effect of convection in melt. The paper gives three parts of work as follows: 1. On the basis of the former results, it gives the mathematical formulation for crystal growth in an external flow with a small Reynolds number; 2. By using the form of Mullins-Sekerka solution and the method of perturbation, it studies crystal growth in an external flow with a small Reynolds number in the coordinate system moving with the interface velocity, obtains the basic steady state solution and the perturbed solutions; 3. It analyzes the influence of an external flow on temperature and fluid field in the solidification of pure aluminum, and draws the conclusions that the temperature fluctuation of the liquid and the solid phase and the horizontal velocity of the liquid phase increase along with the increase in the velocity of the external flow.