Dissimilar heat transfer enhancement in porous channel turbulence

在壁面孔隙率小的情况下，与不透水壁面相比，在表面摩擦系数或斯坦顿数方面没有观察到显著差异。然而，对于大孔隙率的壁，发现湍流的热量和动量传递显著增强引入多孔壁。在热和动量传递之间观察到微弱但不可忽略的差异，即斯坦顿数较高而表面摩擦系数较低。这种差异的物理机制是根据大尺度展向轧辊与其诱导的湍流热通量和雷诺应力的相关性来解释的。

In case of small porosity on the wall, no significant difference has been observed in a skin friction coefficient or the Stanton number in comparison to an impermeable wall. For large wall porosity, however, turbulent heat and momentum transfer is found to be remarkably enhanced by the introduction of the porous wall. Weak but non-negligible dissimilarity, i.e., the higher Stanton number and the lower skin friction coefficient, is observed between heat and momentum transfer. The physical mechanism of this dissimilarity is interpreted in terms of the relevance of the large-scale spanwise rolls with their induced turbulent heat flux and Reynolds stress.