NUMERICAL ASPECTS IN MODELING PHASE-TRANSITIONS BY RATE-TYPE CONSTITUTIVE-EQUATIONS

The paper deals with the possibility to describe phase transitions by means of a Maxwell's rate-type viscoelastic constitutive equation. The equilibrium curve is that of a van der Waals fluid and the relaxation modulus is a power function of the "over-pressure". Estimates for spatially homogeneous solutions in volume and pressure are given. The model has the capability to describe qualitatively the role of "impurities" in nucleation phenomena of phase transition. The numerical method of characteristics is used. We discuss the way the numerical instabilities may be isolated from the physical ones.