在一台住宅热泵上对两台三排热泵蒸发器（室外盘管）进行了测试，以确定翅片分级是否会减缓霜冻增长并改善热泵的结霜/除霜性能。基本线圈的均匀翅片密度为20翅片/英寸。（fpi）（8鳍/厘米）三排。鳍级线圈的前排、第二排和后排鳍间距分别为15 fpi（6鳍/cm）、20 fpi（8鳍/cm）和25 fpi（10鳍/cm）。在28华氏度（2.2摄氏度）和90%相对湿度条件下，以及在35华氏度（1.7摄氏度）和82%和95%相对湿度条件下，评估霜冻/除霜性能。测试了两种气流速度。对前排前缘的霜冻生长进行了测量。 通过蒸发器的湿度测量来估计霜冻质量。确定了霜冻/除霜循环的循环COP。进行了两次稳态冷却试验，以确定翅片分级对冷却能力的影响。与基本情况相比，分级盘管的防冻/除霜性能结果好坏参半。在95%相对湿度和35°F（1.7°C）条件下，分级线圈的COP降低8.7%。在35°F（1.7°C）温度下，分级盘管的霜冻/除霜循环时间从6%减少到30%，具体取决于气流。相比之下，在28°F（2.2°C）的温度下，分级盘管的结霜/除霜循环时间从21%增加到23%。在大多数情况下，分级盘管蒸发器翅片前缘的结霜量较高。 然而，前排较宽的间距允许形成较厚的霜层。这些混合结果与之前测试的两排蒸发器不同。据推测，混合结果可能是由于制冷剂回路未针对测试线圈进行优化。单位:双引文:ASHRAE交易，第108卷，第。2.

Two three-row heat pump evaporators (outdoor coils) were tested on a residential heat pump to determine whether fin staging would slow frost growth and improve heat pump frosting/defrosting performance. The base coil had a uniform fin density of 20 fins/in.(fpi)(8 fins/cm)on the three rows. The fin staged coil had a fin spacing of 15 fpi (6 fins/cm),20 fpi (8 fins/cm),and 25 fpi (10 fins/cm) on the front, second, and back rows, respectively.Frost/defrost performance was evaluated at 28°F (–2.2°C)with 90% relative humidity and at 35 °F (1.7°C) with 82% and 95% relative humidity. Two airflow rates were tested. Frost growth on the leading edge of the front row was measured. Frost mass was estimated from psychrometric easurements across the evaporator. Cyclic COP was determined for the frost/defrost cycle. Two steady-state cooling tests were performed to determine the impact of fin staging on the cooling capacity.Frost/defrost performance results for the staged coil were mixed when compared to the base case.At 95% relative humidity and 35°F (1.7°C), the COP was 8.7% lower for the staged coil. The frost/defrost cycle time decreased from 6% to 30% for the staged coil, depending on airflow, at 35°F (1.7°C). In contrast, the frost/defrost cycle time increased from 21% to 23% for the staged coil at 28°F (–2.2°C). Frost growth on the leading edge of the evaporator fins was higher for the staged coil in most cases. However, the wider spacing on the front row allowed for a thicker frost layer to form. These mixed results were different fro those of previously tested two-row evaporators. It was hypothesized that the mixed results could have been the result of the refrigerant circuiting not being optimized for the coils tested.Units: Dual