An experimental study is carried out on novel twisted-tapes (TTs). First, the performance of discontinuous TTs (DTTs) with both alignment (ADTT) and non-alignment (NDTT) rotations is compared to the continuous TT (CTT). The results show that the heat transfer coefficient (h) decreases by an average of 14.9% and 8.8%, as the ADTT and NDTT are used, and the pressure drop (∆p) decrements are about 23.3% and 18.6%, respectively. The average overall performance index (OPI) of CTT, ADTT, and NDTT is about 1.70, 1.55, and 1.65, respectively. Then, to enhance the performance of the DTTs, the straight sections are equipped with 1, 2, and 3 rows of delta-winglets (DWs). It is found that creating DWs increases both h and ∆p. The enhanced DTTs have two ways to disrupt the flow field, including flow disruption produced by twisting the tape and extra flow disruption produced by creating the DWs. Compared with the original DTTs, the enhanced ADTT and NDTT can effectively improve the thermal performance of the tube under identical operating condition. The values of h for the ADTT and NDTT is increased by 7.4–35.6% and 2.5–45.8%, respectively, and the corresponding OPI ranges from 1.34 to 1.95.

对新型扭曲带（TT）进行了实验研究。首先，将具有对齐（ADTT）和不对齐（NDTT）旋转的不连续TT（DTT）的性能与连续TT（CTT）进行比较。结果表明，当使用ADTT和NDTT时，传热系数（h）平均降低14.9％和8.8％，压降（∆ p）分别降低约23.3％和18.6％。CTT，ADTT和NDTT的平均总体性能指数（OPI）分别约为1.70、1.55和1.65。然后，为增强DTT的性能，直段配备了1排，2排和3排三角形小翼（DW）。发现创建DW会同时增加h和∆ p。增强型DTT有两种破坏流场的方式，包括扭曲带子产生的流破坏和创建DW产生的额外流破坏。与原始DTT相比，增强的ADTT和NDTT在相同的工作条件下可以有效地改善灯管的热性能。ADTT和NDTT的h值分别增加了7.4–35.6％和2.5–45.8％，相应的OPI范围为1.34至1.95。