An experimental investigation of two-phase refrigerant R-410A flow distribution in plate heat exchangers

This study provides an experimental observation of evaporating two-phase refrigerant 410A flow distribution in a plate heat exchanger by the method of Infra-Red Thermography. The test section was made by brazing four stainless steel chevron corrugate plates to form a three flow passages plate heat exchanger. Refrigerant flowed through the central passage of the plate heat exchanger upwardly while water flowed through the outer two side flow passages downwardly to form a counter flow. Two-phase refrigerant R-410A with vapor quality of 0.2 flowed into the heat exchanger through a small hole at various directions as the inlet distributors. An Infra-Red Thermography was installed in front of the plate to measure the plate surface temperature distribution. The test results show that the two-phase refrigerant flowed through the plates fairly uniformly over the entire heat exchanger without inlet distributor. However, while an inlet distributor was applied, since the inlet refrigerant was restricted in a small hole, this caused flow mal-distribution inside the flow passages between the plates. The inlet distributor at direction 12 provided the most uniform flow distribution and that at the direction 3 the least.