rfblumen
Ansys Employee

Assuming that the heat flux value entered is positive, the reason why there may be low temperature values in the model relative to the inlet temperature may be due to the energy equation not being converged.  How is the convergence in terms of the RMS residulas for mass, momentum and energy?  What is the percent imbalance for these equations (found near the end of the CFX .out file under Normalised Imbalance Summary)?

If running with Auto Timescale, sometimed the resulting solid time step is too high.  Check in the out file in the convergence history for the value used for the solid time step.  Change the time step form Auto Timescale to Physical Timescale.  Set the solid timescale to a lower value.

If convergence is reasonable and changing the solid timestep doesn't help, it may be related to skewed or poor mesh.  You could try setting the expert parameter "cht diffusion scheme = 6" (default value is 5). 

If this doesn't work, and the low temperature is only on the GGI, try setting the expert parameter "ggi ap relaxation=0.3".  Note that this will need to be set in the Expert Parameter section by a copy/paste of this command through Edit-in-Command Editor since this is a hidden expert parameter and not exposed in the GUI.  You'll first need to have at least one expert parameter alread set for the Expert Parameter section to be persistent.