Comsol Heat Conduction Using Identity Pairs

[zer0c123]

I'm trying to do a simple transient analysis of conduction through 2 interfaces. My test run is basically 2 cubes of 100 mm length. One cube at an initial temperature of 1800K and the other with initial T at 273.15 K. Both using library material properties for AISI 4340 steel. After observing the plots, the temperature of one cube constantly stayed at room temperature, so it seemed there was no heat flow through one of the cubes. I've reread the documentation on assigning identity, and believe that I have done it right. Well maybe..

Procedure
1. Draw 2 cubes of 100mm length
2. Select Draw->Create pairs.
3. Physics -> Identity pairs->identity Boundary pairs
4. Select 1 source face from cube 1 and 1 destination face from cube 2.
5. Apply Sub domain and Boundary conditions with ambient temperature.

Any input would be appreciated.

 

[zer0c123]

Do the 2 cubes need to be actually stuck together in Comsol? I drew the 2 cubes far apart, because I was assuming that Comsol would understand the continuity relationship from the identity pairs. Therefore the program shouldn't require the 2 cubes to be combined at the interface.