The separation efficiency is divided by the mass of the oil in the overflow and then by the total mass of the input oil. Where did you see it? You still take it for granted! I know that both cyclone separator and cyclone separator use dpm model to simulate the ratio of the number of particles at the exit to the number of particles entering. I think this is more scientific than yours, but I still ... I come from the definition of cyclone separation efficiency, and I don't know if the mass flow of oil phase at the overflow port and inlet simulated by mixture model is accurate.
Whether DPM or mixture is used depends on ion concentration. Now I am also studying these two models, hoping to communicate.