MOMOP vs. SELEC block settings for phase transitions in ECO2M
I see that MOMOP(29) allows us to define how we would like to perform phase transitions ("hairtrigger" vs. "finite window"), but the ECO2M module also allows us to set that in the SELEC block. In this case (and in others where functionalities are duplicated), which setting takes priority?
Here it goes:
(1) The "hairtrigger vs. finite window option" was originally implemented by Karsten Pruess in TOUGH2-ECO2M, with parameters specified in the SELEC block. ECO2M was then integrated into iTOUGH2; iTOUGH2-ECO2M still (only) uses the SELEC parameters to ensure backwards compatibility with TOUGH2-ECO2M.
(2) This being considered a useful option, it was also integrated into various other EOS modules. Since some of these modules make use of the SELEC block for different purposes, MOP2(29) and MOP2(30) (only available in iTOUGH2) were defined to invoke the finite-window option.
(3) The finite-window option was implemented into the following iTOUGH2 EOSs: 1, 1SC, 2, 3, 4, 5, 7, 7R, ECO2N, and EWASG.
Use SELEC for ECO2M (for backwards compatibility with the existing TOUGH2-ECO2M module), but use MOMOP for the iTOUGH2-EOSs listed under (3) above for consistency and to avoid conflicts with other SELECT parameters.
While certainly confusing, this is the best compromise I could come up with.