헤더 입구 형상에 따른 평판관 열교환기의 냉매 분배

The refrigerant R-134a flow distributions are experimentally studied for a round header/ten flat tube test section simulating a brazed aluminum heat exchanger. Three different inlet orientations (parallel, normal, vertical) were investigated. Tests were conducted with upward flow for the mass flux from 70 to 130 kg/㎡s and quality from 0.2 to 0.6. In the test section, tubes were mounted with half protrusion into the header. It shown that distribution with vertical inlet is superior than others. Possible explanation is provided based on flow visualization results.