A circulating liquid concept should increase energy efficiency, reduce inventory and leakage of expensive and environmentally damaging refrigerant, and utilize centralized units that are more reliable, efficient, and less expensive. The project determines viable fluids, appropriate defrost technique, and will experimentally verify models developed. Additional attention is given to CO2 and ice slurry as secondary fluids that operate with phase changes. The Trane Co. The goal is to investigate maldistribution and fractination in brazed plate heat exchangers, especially when operating with lower mass velocities.
Special attention is focused on the stability of the superheat signal.
Oil hold-up is investigated along with different distribution options. The final task is to develop and test ways of integrating ducted evaporators into a display case in a manner compatible with efficient operation of its air curtain. The transcritical CO2 cycle is very promising at low-temperature lifts, particularly for heat pumps. We are comparing the performance of several in-house developed systems to the baseline R410A system that is the best conventional system available. The ultimate goal is to understand and control laser beams irradiating solids to create high-intensity filaments on the order of microns.