    
rgnelson
Moderator
Username: rgnelson
Post Number: 1339
Registered: 06-2003
| | Posted on Friday, March 26, 2010 - 07:49 pm: | |
FlexPDE uses an implicit second-order Backward Difference method to advance in time, and should not be subject to Courant conditions.
The timestep is controlled by examining the deviation of the time behavior of the variables from quadratic time polynomials. The user control ERRLIM selects how closely the behavior must adhere to quadratic evolution. (ERRLIM controls both space and time accuracy. TERRLIM controls time behavior only.)
There is no explicit timestep control mechanism other than SELECT FIXDT, which expects that the TIME section will specify a single constant timestep.
|