Hi, I have tried to set up a simple 1D moving boundary problem with a phase change material and track the phase front. We get agreement with the analytical solution for Fluent Ver. 6.2 but not for Ver. 6.1. The tutorial case file in Ver. 6.1 works fine but is too complicated for a start. Are there differences in the two Fluent versions for the solidification/melting model? Has somebody set up a simple 1D moving boundary problem in Ver. 6.1 successfully? Thomas

This was one example from the literature, which didn't work with Fluent Ver. 6.1:

Phase change material ice: Density d=1000 kg/m3 Specific heat Cp=4187 J/kgK Thermal conductivity k=0,564 W/mK Latent heat L=333400 J/kg Melting temperature Tm=273 K Initial temperature T0=272.95 K (solid)

Dimensions/mesh: 0.1 x 10 cm (Mesh 1x100)

Boundary conditions: Left wall: T = 298 K (25°C) Right wall: Heat flux = 0 W/m2 Bottom/top: symmetry

I calculated the phase front position analytically and the result is also given in the literature below:

The phase front should reach 1cm at 1301 sec.

Has somebody verified successfully an 1D melting problem in Fluent 6.1 with an analytical solution?

Thomas

Literature: Alexiades, V., Solomon, A.D. (1993) Mathematical modeling of melting and freezing processes, Hemisphere Pub., p. 40ff

Hi Thomas,

I'm having some problems in solidification/melting model too.

I have this glass sphere container containing PCM (initially solid), where hot water will be circulating around the outer surface of the sphere.

should VOF be used in this case? I need to see the phase change of the PCM. How do i go about...

Can u pls help...

Lim.