I want to use time=day instead of second in my analysis (to identify element permeability). Does this mean i should convert all time units to day? (including gravity m/day2 instead of 9.81 m/s2)?
Yes, you can define your time unit to be anything you like (day, second, moon phase), just as long as you are *consistent* throughout the rest of the modeling.
Thanks, but the numbers will be very weird and huge if i do so (for g gravity and water specific gravity). i tried to do simple analysis that i know it converges if i use seconds, but it didn't converge at all when i changed all units to day.