### TemperateIce stability issues

Posted:

**09 Jun 2015, 16:19**Hi all,

I'm encountering some strange convergence issues in the temperature solver in a coupled NS/Heat equation + mesh update spinup run.

Although my simulation is transient, I'm attempting to solve the steady state temperature equation by specifying:

in the TemperateIce solver section.

Interestingly, this seems to work (though it takes a while to converge) if I switch off the Mesh Update solver, but not if it is on. The strange part is, if I specify in the body force:

such that I get a "solution trivially zero" (i.e. Mesh Update solver doing nothing), I still get a breakdown error...

This is really confusing me. It seems as if MeshSolve.F90 is doing something, aside from displacing the mesh, which is messing up the temperature solution on the following timestep.

A final piece of the puzzle: If I turn off:

then it seems to behave, even with the mesh update.

If anyone has any ideas what might be causing this, I'd be very grateful!

I'm encountering some strange convergence issues in the temperature solver in a coupled NS/Heat equation + mesh update spinup run.

Although my simulation is transient, I'm attempting to solve the steady state temperature equation by specifying:

- Code: Select all
`Steady State Condition = Real 1.0`

in the TemperateIce solver section.

Interestingly, this seems to work (though it takes a while to converge) if I switch off the Mesh Update solver, but not if it is on. The strange part is, if I specify in the body force:

- Code: Select all
`Mesh Update = Real 0.0`

such that I get a "solution trivially zero" (i.e. Mesh Update solver doing nothing), I still get a breakdown error...

This is really confusing me. It seems as if MeshSolve.F90 is doing something, aside from displacing the mesh, which is messing up the temperature solution on the following timestep.

A final piece of the puzzle: If I turn off:

- Code: Select all
`Temp Load = Variable Velocity 1`

Real Procedure "ElmerIceUSF" "getFrictionLoads"

then it seems to behave, even with the mesh update.

If anyone has any ideas what might be causing this, I'd be very grateful!