Performance of the refrigeration system with capillary injection in evaporator.

It is interesting to improve the performance efficiency of the refrigeration system by the utilization of the high pressure refrigerant. Based on the field synergy theory, a new type of refrigeration system was provided, in which the high pressure refrigerant was injected into the evaporator coil from the hole opened on the capillary inserted in the evaporator coil. The change law of the synergy angle between the flow and heat flow along the hole diameter and the capillary diameter was analyzed theoretically. And the visual experiments were carried out. The theoretical results show that the synergy angle is reduced with the decrease of the hole diameter and the capillary diameter, but the effect of capillary diameter is also reduced with the decreasing of the capillary diameter. The experimental results show that compared with the conventional refrigeration system, the refrigerant mass charge is reduced more than 70%, COP is improved by 9% and the time to reach the stable state is reduced by 70%.