Design and visualized validation of a distributor with uniform refrigerant distribution by forming annular flow

To resolve the problem of non-uniform refrigerant distribution in multi-path heat exchangers of air conditioners, a new distributor which distributes the two phase refrigerant uniformly is presented. The basic idea to develop the new distributor is firstly to construct a symmetric annular flow before distribution and then to allocate the annular flow evenly. The detailed design method, including an approach for computing the inlet tube geometry to construct the annular flow, and an approach for designing the connection structure between the inlet tube and the outlet tubes to allocate the annular flow evenly, is presented. The new distributor prototype is made of transparent material and the flow pattern inside it is observed visually. The experimental results show that the distribution unevenness of the proposed distributor under the horizontal and the vertical installations are respectively 19.8% and 60.9% lower than those of the most commonly used cone-type distributor. (C) 2018 Elsevier Ltd and IIR. All rights reserved.