Numerical simulation study of optimal inlet conditions of rectifier nozzle type distributor

Abstract

Objective: In order to effectively improve or eliminate as much as possible in the refrigeration system, the uneven distribution of gas-liquid two-phase refrigerant in the evaporator leads to the performance decline of the refrigeration system. Methods: The adopts CFD numerical simulation method was used to establish the physical model of rectifier nozzle type distributor and mathematical model of gas-liquid two-phase flow, based on the mixture model in multiphase flow model, which simulated the phase distribution and the degree of gas-liquid two-phase separation inside this distributor,. Then the influence of inlet conditions (inlet flow rate and mass flow fraction of gas) on the uniformity of diverter distribution was analyzed. Results: The results showed that when the inlet flow rate was 1 m/s and the mass flow fraction of gas was 0.2, the flow pattern gradually stabilizes and a uniform annular flow could be formed. Under the control of these conditions, the overall unevenness of the distributor reached the minimum value and had the best effect of liquid separation. Conclusion: On the basis of optimizing the structure of the distributor, the flow pattern can be further adjusted by adjusting the inlet condition to the best, and the symmetrical annular flow can be formed to realize uniform liquid separation.

Keywords

• distributor
• cfd numerical simulation
• two-phase flow
• distribution uniformity
• inlet conditions