Simulation and experimental study on splitting performance of Rectifier Nozzle Type Critical Distributor for multi-parallel evaporators

Abstract

To solve the problem of performance degradation of multi-parallel evaporator due to inhomogeneous refrigerant distribution, a Rectifier Nozzle-Type Critical Distributor (RNCD) was developed. The multi-parallel evaporator test bench with RNCD and Centrifugal Distributor (CD) was built and the four parameters of cooling rate, outlet degree of overheat, pressure drop and cooling capacity of multi-parallel evaporator with RNCD were analyzed. Research shows that: The application of RNCD can improve the uniformity of superheat and cooling capacity while increasing the cooling rate of the system. When evaporator temperature is -28 °C, the ratio of overheat inhomogeneity of RNCD than CD was reduced by 0.58, and the ratio of cooling capacity inhomogeneity of branches was reduced by 0.45. The total pressure drop of the three components is roughly the same as that of the evaporator. RNCD can bear more pressure drop of the throttle valve. Combined with the simulation of experimental conditions, the study shows that RNCD has better distribution ability and can play the role of secondary throttle pressure drop. The RNCD proposes a novel approach to addressing the issue of inhomogeneous refrigerant distribution in refrigeration system as well as the optimization of the refrigeration system.