>>> DELTFACT: deltfact
In TOUGH2, time step size can be controlled in various ways (see Pruess  for a description of input variables DELTEN, DLT, DELTMX, NOITE, REDLT, and MOP(16)). The time step is also automatically adjusted in order for the simulation time to land on any of the specified calibration or printout times. This may lead to very small time steps or even convergence failures (see command >>> CONSECUTIVE). In iTOUGH2, the proposed time step is increased up to a factor of DELTFACT (default: 1.2) if this increase allows the simulation to reach the next calibration or printout time. This may lead to time stepping different from standard TOUGH2.
>>> DELTFACT: 1.0 (as in standard TOUGH2)
>>> allow : 20 CONSECUTIVE time steps converging in 1 iteration