Thermal conductivity in dynamics of first-order phase transition

Effects of thermal conductivity on the dynamics of first-order phase transitions are studied. Important consequences of a difference of the isothermal and adiabatic spinodal regions are discussed. We demonstrate that in hydrodynamical calculations at non-zero thermal conductivity, $\kappa \mathrm{\ne }0$, onset of the spinodal instability occurs, when the system trajectory crosses the isothermal spinodal line. Only for $\kappa =0$ it occurs at a cross of the adiabatic spinodal line. Therefore ideal hydrodynamics is not suited for an appropriate description of first-order phase transitions.