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 dryness 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 inlet mass-flow rate contributes the most significantly to the separation efficiency. In the effective separation area， when the flow rate increases from 18 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.