This is a numerical study of convective heat transfer of the Water-Al₂O₃ nanofluid in an oval channel using two-phase mixture model. The channel is fitted with two rows of twisted conical strip inserts with various directions relative to each other leading to three different combinations of the mentioned inserts, namely inward Co-Conical inserts (CCI-inward), Counter-Conical inserts (CoCI), and outward Co-Conical inserts (CCI-outward) in which its lower wall is exposed to a constant heat flux. The effect of Reynolds number ranging from 250 to 1000, nanofluid volume fraction ranging from 1 to 3 % and conical strip insert combinations are examined on the fluid flow patterns and heat transfer characteristics. The results showed that among the three combinations of the twisted conical strip insert, CCI-inward locally presents the highest values of heat transfer coefficient, as about 17% higher than plain tube, considering the nature of the secondary flow created in this case. It is also found that the effect of increasing nanofluid concentration on the channel thermal performance is more significant at higher values of $Re$ number; however, the pressure drop difference between the three models is subtle.

这是水-Al ₂ O ₃对流传热的数值研究两相混合模型在椭圆形通道中形成纳米流体。通道装有两排扭曲的锥形条形插入件，其方向彼此不同，从而导致上述插入件的三种不同组合，即向内的圆锥形插入件（CCI向内），对角的锥形插入件（CoCI）和向外的圆锥形刀片（CCI向外），其下壁暴露于恒定的热通量。研究了雷诺数在250到1000之间，纳米流体体积分数在1-3％之间以及圆锥形条形插入物组合的影响，研究了流体的流型和传热特性。结果表明，在扭曲的锥形条形插入件的三种组合中，向内的CCI局部呈现最高的传热系数值，比普通管高约17％，考虑在这种情况下创建的二次流的性质。还发现增加纳米流体浓度对通道热性能的影响在较高的值下更为显着。$\mathrm{[R}Ë$数; 但是，这三个模型之间的压降差很小。