One reminds that according the temperature difference seen on all nodes of the domain at the previous time step (time step n), SYRTHES estimates the value of the following time step (ie time step n+1) so that the temperature do not change more than the specified temperature difference.
This process needs to be initialized for the first time step. Even if
the time step will adapt progressively, authors
advises to choose wisely this value and set for example
the value they would have chosen if doing a constant time step
calculation.
When ignoring what to set, it is sometime better to choose
a smaller value than a greater value for this initial time step value.