why we use super compressibility factor in orifice meter equation instead of compressibility ratio as in turbine meter correction equation?

 

you have to read the literature you are referencing very carefully

Supercompressibility refers to a correction factor that involves the square-root of the compressibility factor at the base conditions and that at flowing conditions.

be very careful as the meter coefficient make many assumptions regarding base conditions (P,T) and even that of the conversion factor involved in the meter differential from one set of units to another.