International Journal of Refrigeration
Derun Zhanga, Liang Puac, Luozhu Niana, Zhongyi Menga, Tangtang Gub, Min Liub, Yachen Zhoub
aDepartment of Refrigeration and Cryogenic Engineering, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China
bNingbo AUX Electric Co., Ltd, Ningbo, Zhejiang 315191, China
cKey Laboratory for Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
In the residential air-conditioning system, the mal-distribution of the two-phase refrigerant deteriorates the performance of the multi-channel evaporator, especially in distributors. In this paper, the distribution uniformity and structural optimization of a type of air-conditioning distributor are investigated with simulation models and experiments. Two types of optimized distributors are proposed through the study on multiple structural factors, the Taguchi method and the summary of flow mechanism. Furthermore, the relevance between the mal-distribution and the performance of the evaporator is established by a heat exchanger design software. The results show that the distributor can alleviate the uneven phase distribution at the inlet through the following three effects: throttling of the orifice, diffusion and backflow in the cavity. Improvements are proposed based on these points, including enlarging the space of the mixing cavity and applying a hemispherical surface. It is confirmed that the optimized distributors have better performance compared to the original sample by simulation evaluations and experimental verifications. The non-uniformity index of optimized distributors reduced by 4.6% and 36.5%, respectively.