在一台住宅热泵上测试了三个两排热泵蒸发器（室外盘管），以确定翅片分级是否会减缓结霜增长，并在严重结霜条件下改善热泵结霜/除霜性能。基本线圈的均匀翅片密度为20翅片/英寸。（fpi）（每厘米8个鳍）。检查了两个翅片级线圈。第一个（案例一）的前排和第二排鳍间距分别为15 fpi（6鳍/cm）和20 fpi（8鳍/cm）。第二个（案例二）的前排和第二排鳍间距分别为15 fpi（6鳍/cm）和25 fpi（10鳍/cm）。在28ºF（-2.2ºC）和90%相对湿度条件下，以及在35ºF（1.7ºC）和95%相对湿度条件下，对霜冻/除霜性能进行了评估。在35ºF（1.5℃）下测试了通过翅片级线圈的三种气流速率。 7ºC），相对湿度为82%。对前排前缘的霜冻生长进行了测量。霜冻质量是通过蒸发器的湿度测量来估算的。计算霜冻/除霜循环的循环COP。在35ºF（1.7ºC）下，情况1和情况2级线圈比基本情况下提高了霜/除霜COP 8.7%，而在28ºF（-2.2ºC）下，情况1线圈降低了循环COP4。5%的情况下，双线圈降低循环COP 9.0%。翅片分级将霜冻/除霜循环时间从32%增加到100%，具体取决于室外条件。两个分级盘管延迟了蒸发器翅片前缘的结霜，尽管湿度测量表明室外气流中的水分去除增加。 这些趋势表明，staging成功地将霜冻生长转移到远离前排前缘的位置。气流的减少使COP降低了8%，循环时间减少了57%。第二种情况就更少了。单位:双引文:阿什雷交易，第107卷，第。2.

Three two-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 at heavy frosting conditions. The base coil had a uniform fin density of 20 fins/in. (fpi) (8 fins/cm) on both rows. Twofin staged coils were examined. The first (Case One) had fin spacing on the front and second rows of 15 fpi (6 fins/cm) and 20 fpi (8 fins/cm), respectively. The second (Case Two) had fin spacing on the front and second rows of 15 fpi (6 fins/cm) and 25 fpi (10 fins/cm), respectively. Frost/defrost performance was evaluated at 28ºF (-2.2ºC) with 90% RH and at 35ºF (1.7ºC)with 95% RH. Three airflow rates through the fin staged coils were tested at 35ºF (1.7ºC) with82% RH. Frost growth on the leading edge of the front row was measured. Frost mass was estimated from psychrometric measurements across the evaporator. Cyclic COP was calculated for the frost/defrost cycle. The Case One and Case Two staged coils improved frost/ defrost COP 8.7% over the base case at 35ºF (1.7ºC), while at 28ºF (-2.2ºC), the Case One coil reduced cyclic COP4.5% and the Case Two coil reduced cyclic COP 9.0%. Fin staging increased frost/defrost cycle time from 32% to 100%, depending on outdoor conditions. Both staged coils delayed frost growth on the leading edge of the evaporator fins even though psychrometric measurements indicated an increase in moisture removal from the outdoor airstream. These trends suggested that staging was successful in moving frost growth to locations away from the leading edge of the front row. Decreased airflow reduced COP up to 8% and reduced cycle time by up to 57%. These were less for Case Two.Units: Dual