Diffuse Interface (D.I.) Model for Multiphase Flows

  • Andrea G. Lamorgese
  • Dafne Molin
  • Roberto Mauri
Part of the CISM Courses and Lectures book series (CISM, volume 538)


We review the diffuse interface model for fluid flows, where all quantities, such as density and composition, are assumed to vary continuously in space. This approach is the natural extension of van der Waals’ theory of critical phenomena both for one-component, two-phase fluids and for liquid binary mixtures. The equations of motion are derived, showing that the problem is well posed, as the rate of change of the total energy equals the energy dissipation. In particular, we see that a non-equilibrium, reversible body force appears in the Navier-Stokes equation, that is proportional to the gradient of the generalized chemical potential. This, so called Korteweg, force is responsible for the convective motion observed in otherwise quiescent systems during phase change. Finally, the results of several numerical simulations are described, modeling, in particular, a) mixing, b) spinodal decomposition; c) nucleation; d) heat transfer; e) liquid-vapor phase separation.


Free Energy Binary Mixture Multiphase Flow Peclet Number Spinodal Decomposition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© CISM, Udine 2012

Authors and Affiliations

  • Andrea G. Lamorgese
    • 1
  • Dafne Molin
    • 2
  • Roberto Mauri
    • 3
  1. 1.Department of Chemical EngineeringThe City College of CUNYNew YorkUSA
  2. 2.Department of Energy TechnologyUniversity of UdineUdineItaly
  3. 3.Department of Chemical Engineering, Industrial Chemistry and Material ScienceUniversity of PisaPisaItaly

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