Cavitation characteristics and suppression research of refrigerant in capillary tube

Abstract

Abstract Cavitation is easy to form and develop due to the large pressure drop during throttling in the refrigeration system. To effectively suppress the throttling cavitation phenomenon, an aerating method through bypass capillary is proposed. Based on the Homogeneous Equilibrium Mixture (HEM) model, the Schnerr-Sauer cavitation model and the Realizable k-ε turbulence model were adopted, and the throttling process in the capillary tube and transition tube was simulated by Fluent, and the pressure distribution and vapor volume fraction distribution in the capillary tube and transition tube were obtained for both original model and aerating model. Results show that after adopting the aerating technology, the vapor volume fraction at the capillary outlet is almost unchanged, while the vapor volume fraction in the transition tube is obviously increased, which indicates that the bubble collapsing phenomenon in the transition tube is weakened, and then realized the purpose of suppressing the cavitation effect.