Have you reviewed this? https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v231/en/flu_ug/flu_ug_sec_melt_inputs_steps.html
To add, with a 1s time step you could be adding a lot of heat into the model very quickly: how was the convergence looking?
You are navigating away from the AIS Discovery experience