22. Solidification Module Algorithms

The use of the solidification module allows the user of PHYSICA to model phase change processes as a result of materials changing from a liquid to solid phase or vice versa. The module calculates a liquid fraction value for each element. This value represents the proportion of the element which is liquid. This fraction acts as a restriction to the flow and also, as the fraction changes, as source of heat. In most cases energy is released as a material solidifies. This change in energy can cause problems as it can raise the element temperature which reverses the solidification process. In an attempt to avoid the problems caused by alternate solidifying-melting a set of correction methods are employed to calculate the liquid fraction.