Horizontal distribution of two-phase refrigerant in parallel flat mini-channels

A literature survey revealed that no prior investigation has been conducted on the horizontal distribution of a two-phase refrigerant in mini-channel tubes, which may be of importance for the cooling of heat-generating objects. In this study, we investigated R-134a distribution into four flat tubes inside a horizontal plane. In order to simulate the battery of an electric vehicle, a 600-W power supply was used during our tests. Tests were conducted with mass fluxes ranging from 280 to 480 kg m−2s−1 and an inlet quality of 0.2. The effects of inlet port orientation and heat exchanger inclination on flow distribution were investigated. Results indicated that the effects of heat exchanger inclination on flow distribution were more prevalent than those of inlet port orientation. However, these effects are weakened as mass flux increases. Flow distribution deteriorated as the inclination of the heat exchanger increased. Header pressure drop constituted a significant portion of heat exchanger pressure drop and became more pronounced as mass flux increased.