Melting system, mathematical analysis

In a mathematical analysis of the melting system the mass balance around the melting system (Fig. 12.8) shows that the amount of melt dragged from under the solid and left on the barrel has to equal the rate at which solid is melted. In Fig. 12.8 we see that at steady state, the solid moves in the y direction, towards the barrel surface, at a velocity Vy as the melt is dragged away by the barrel. The melting rate is designated as O and is given in units... 

The foregoing survey was focused on situations where bnlk diffusion processes were rate determining. Such systems are amenable to analysis using an electrochemical approach. Other factors such as transport down pores or cracks, volatilization or melting of the oxide scale may occur and require different analyses but diffusion controlled processes may be mathematically modeled and correlated with the defect chemistry of the corrosion product. These limiting cases provide a guide to understanding the more complex phenomena frequently encountered. 

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