Study On The Performance Of Refrigerant Distributor

In refrigeration system，refrigerant flow through expansion devices andflows into evaporator as two-phases state. Whether the refrigerant can beevenly distributed into each branch will influence the performance ofevaporator significantly，even to the whole refrigeration system. Refrigerantdistributor is an important auxiliary device for refrigeration system，which isused before evaporator，make the two-phase refrigerant flows into eachbranch evenly.Based on the literatures，patents and market survey，the distributorsexisted cannot makes uniformity distribution. Three types of distributorswere researched including their mechanism and performance throughexperimental and CFD method. The factors which influence distributors’performance such as mass flow rate，inlet quality，installation angel andlength of capillaries were studied. What is more，according to CFD analysisand Taguchi optimization method，investigate the influence of geometryfactors of reservoir distributor such as body diameter，length and ratio ofthem and optimize performance.The main contents and results of this study are as below:1) Built refrigerant distributor test rig which can measure the mass flowrate and quality of each branch. Manufactured two samples for eachdistribution mechanism refrigerant distributor and test their performance. Quantitative study on how the mass flow rate and inlet quality influence thedistributors’performance.2) Based on computational fluid dynamics software FLUENT，builtsimulation models and calculated with Euler multiphase model and k-epsilon/Reynolds Stress Turbulence models. Compared with experimental results，deviation is under15%which shows high accuracy. Through CFD analysis，detail information of pressure and phase distribution can be plotted，the keyparameters which influence distributor performance were found andoptimized.3) Compared with cyclone and jet type distributors，reservoir distributor isnot affected by mass flow rate，quality and installation angel. What is more，its structure is simple and pressure drop is lower，which deserved furtherresearch. According Taguchi optimization method and CFD analysis，it isfound that the diameter and height of distributor influence the performancesignificant because it decides the effect between gravity and inertia force.4) Based on experiment，the installation angels and length of capillarieswere researched. A numerical model for distributor performance predictionwas built which can calculate and quantitatively evaluate how the capillaryinfluence the refrigerant distribution.