Experimental Study on Header-Orifice Vapor-Liquid Separation Unit Using Zeotropic Mixture

Vapor-liquid separation technology can enhance heat transfer while reducing pressure drop. The vapor-liquid separation unit is key to achieving efficient vapor-liquid separation. A visualization experiment of the header-orifice separator is conducted in this study using the zeotropic mixture R1234ze (E)/R32 (mass fraction ratio, 80/20) to investigate the vapor-liquid separation characteristics under different conditions and obtain the effective separation range. The results show that increasing the inlet vapor quality, reducing the inlet mass-flow rate, increasing the flow cross-sectional area of the lower outlet branch, and expanding the separation aperture can improve the separation efficiency, among which the separation efficiency is most sensitive to the inlet mass-flow rate. In the effective separation area, when the flow rate increases from 18 g/s to 12 g/s, the separation efficiency increases by 14.0%. The inlet mass-flow rate, valve opening, and separation aperture minimally affects the size of the effective separation dryness range; however, for the deviation of the effective separation area dryness range, the inlet mass-flow rate exerts the greatest impact, followed by the separation aperture, whereas the valve opening exerts the least impact.