The influence of longitudinal location of curved delta winglet vortex generator on the heat transfer of a finned-tube heat exchanger is numerically studied. The vertical right-angled side of the winglet vortex generator is arranged facing the main flow direction. Longitudinal vortex intensity and heat transfer are obviously affected by the longitudinal location of the vortex generator. There is an optimal longitudinal location of vortex generator for the largest heat transfer performance. At the optimal location, Nusselt number increases by 15.2%–43.9% and 5.4%–9.8%, while friction factor only increases by 12.2%–15.7% and 4.8%–12.2% compared with the plain fin and the original location, respectively. Thermal performance factor of the optimal longitudinal location increases by 8.1% compared with the original location and reaches up to 1.38. The pressure loss of the curved vortex generator is obviously smaller than that of the corresponding straight vortex generator. Good corresponding relationship exists between the Nusselt number and the intensity of longitudinal vortices, which means the intensity of the secondary flow determines the heat transfer. The results are of significance for the design and optimization of the studied finned-tube heat exchanger with curved delta winglet vortex generators.

数值研究了弯曲三角翼小涡流发生器的纵向位置对翅片管换热器传热的影响。小翼涡流发生器的垂直的直角侧朝向主流方向。纵向涡流强度和传热明显受到涡流发生器纵向位置的影响。涡流发生器的最佳纵向位置具有最大的传热性能。在最佳位置，与普通鳍和原始位置相比，努塞尔特数分别增加15.2％–43.9％和5.4％–9.8％，而摩擦系数仅增加12.2％–15.7％和4.8％–12.2％。最佳纵向位置的热性能系数与原始位置相比增加了8.1％，最高达到1.38。弯曲涡旋发生器的压力损失明显小于相应的直线涡旋发生器的压力损失。努塞尔数与纵向涡旋强度之间存在良好的对应关系，这意味着二次流的强度决定了传热。该结果对所研究的带有弯曲三角翼小涡流发生器的翅片管换热器的设计和优化具有重要意义。