Air flow and heat transfer through a rectangular channel equipped with transversely twisted-turbulators are studied experimentally. Three twist-angles and two pitch-ratios are considered to explore the effects of design factors. To create a better understanding of possible mechanisms, a numerical simulation is also carried. The experimental data show that decreasing twist-angle and pitch-ratio increases both h and Δp. Among the studied models, the 0° turbulators give the highest values, followed by the 90° and 180° turbulators come in the second and third, respectively. The use of 0° turbulators enhances h by about 141.2 % at pitch-ratio of 1.875 and 109.4 % at pitch-ratio of 3.75, but these enhancements for the models with 90° and 180° turbulators are 133.2 %–102.7 % and 54.6 %–42.1 %, respectively. The numerical results display that the 0° turbulators are more effective in fluid dispersion towards hot walls and generate stronger swirl flows. However, the best overall performance is seen for the 90° turbulators. It is also found that at min. Re, the models with lower pitch-ratio show a better overall performance, while at the max. Re, an inverse outcome is found. The highest performance index of 1.62 is recorded for the 90° turbulators at the Reynolds number of 1643.

实验研究了通过装有横向扭曲湍流器的矩形通道的气流和热传递。考虑了三个扭转角和两个螺距比，以探讨设计因素的影响。为了更好地理解可能的机制，还进行了数值模拟。实验数据表明，减小扭转角和节距比会同时增加h和Δp。在研究的模型中，0°湍流器的数值最高，其次是90°和180°湍流器，分别位居第二和第三。使用0°湍流器可提高h在1.875的螺距比下大约增加了141.2％，在3.75的螺距比下增加了109.4％，但是对于带有90°和180°湍流器的模型，这些增强分别为133.2％–102.7％和54.6％–42.1％。数值结果表明，0°湍流器在流体向热壁扩散方面更有效，并产生更强的旋流。但是，对于90°湍流器，整体性能最佳。还发现在最小。再者，具有较低螺距比的模型显示出更好的整体性能，而最大 Re，找到相反的结果。90°湍流器的最高性能指数为1.62，雷诺数为1643。