Dear member

i went through Reservoir Engineer handbook authored by tarek ahmed
where he mentioned the following two analytical equation that generally uses reservoir enginner in simulation for capillary pressure curve generation
for oil-water
Pcwo=(Pc)@Swc * ((1-sw-sor)/(1-Swc-Sor))^np

for gas water
Pcgo=(Pc)@Slc *((Sg-Sgc)/(1-Slc-Sgc))^npg
where
Slc=Swc+Sorg
my question is how this exponent i.e. np and npg are calculated from laboratory data
if some body can explain the detail procedure for calculation to be perform in excel
it will be helpful for us