The thermal and hydraulic performance of a twisted circular tube with an obstacle attached to the internal surface along the tube length (L = 1000 mm) is numerically analyzed in this work. The considered configuration is investigated by varying obstacle height ratio (OHR = h/D) which is the obstacle height (h) to the tube diameter (D = 20 mm) while obstacle thickness is kept constant under turbulent flow regime, i.e. Reynolds number 4000 ≤ Re ≤ 10,000 for air as working fluid. Various cases of OHR are triggered 0.0, 0.125, 0.25, 0.375, 0.5 and 0.625 respectively. The results show that the larger OHR gives a higher Nusselt number and vice versa due to increasing swirling power to the air in the tube. However, a higher friction factor is the penalty associated with this large obstacle. Recorded thermal performance factor TPF is beyond unity for all cases. The optimal value of TPF is observed at OHR = 0.625 which is recommended for high heat transfer rate requirement. Corresponding TPF = 2.07 at Re = 4000 and TPF = 1.69 at Re = 10,000. The results are validated against the findings of the previous works and the comparisons show good agreements.

在这项工作中，数值分析了沿管长 (L = 1000 mm) 在内表面附有障碍物的扭曲圆管的热力和水力性能。通过改变障碍物高度比 (OHR = h/D) 来研究所考虑的配置，障碍物高度比 (h) 与管径 (D = 20 mm) 之比，而障碍物厚度在湍流状态下保持不变，即雷诺数 4000 ≤ Re ≤ 10,000 空气作为工作流体。OHR 的各种情况分别触发 0.0、0.125、0.25、0.375、0.5 和 0.625。结果表明，较大的 OHR 产生较高的努塞尔数，反之亦然，这是由于管中空气的涡流功率增加。然而，更高的摩擦系数是与这个大障碍相关的惩罚。记录的热性能系数TPF在所有情况下都超出统一。在 OHR = 0.625 时观察到TPF的最佳值，建议用于高传热率要求。相应的TPF  = 2.07（Re = 4000）和TPF  = 1.69（Re = 10,000）。结果与先前工作的结果进行了验证，并且比较显示出良好的一致性。