What is C_U(c,t) in the UDF for two-phase flow?
 

Hello, everyone. I used C-U(c,t) where c is cell and t is the thread of the gas-phase in two-phase flow in order to get the velocity. However, I am confused that C_U(c,t) is the physical velocity of the gas phase or the superficial velocity of the gas phase? Thanks in advance.