Alluvial channels with sinuosity follow an altered flow behavior, contradictory to straight flows. At the interface of surface water and groundwater, seepage is a significant phenomenon occurring at the boundary of alluvial channels. The study of turbulence in seepage affected sinuous alluvial channels would thus provide us with a better insight into their hydro-morphological behavior. To address the nature of turbulence in sinuous channel with downward seepage an experimental framework was design. The paper reports the structure of turbulence in the sinuous channel for no seepage and seepage flow. With downward seepage, there is a noticeable shift of Reynolds shear stress at near-bed, which reports more momentum transport. The average streamwise and transverse turbulence intensity increased by 3.8–18.5% and 4–10.6%, respectively with downward seepage. Calculation of Kolmogorov complexity and the Kolmogorov complexity spectrum suggests higher randomness in the outer region, which can be associated with excess momentum transport. In the lower flow depth \( \left( {{\text{z}}/{\text{h}}} = 0.2 \right)\), the randomness in the transverse velocities is higher in the outer region of the bend for about 25% and 38% compared to the central and inner region of the bend, respectively. With downward seepage, randomness increased especially in the outer region. This increase in randomness may report the erosive action in the outer part of the bend. Permutation entropy provided an informative measure to study the complex behavior of the transverse velocity time-series, which we found to be higher in the outer flow zone. For downward seepage, mean of entropy increased across the bend. The turbulent flow alterations and increase in randomness with seepage may be helpful to understand the flow in seepage affected sinuous alluvial channels.

具有波纹度的冲积通道遵循改变的流动特性，与直流相反。在地表水和地下水的界面处，渗流是在冲积河道边界处发生的重要现象。因此，研究渗流影响的弯曲冲积通道中的湍流将使我们对它们的水力形态行为有更好的了解。为了解决向下渗流的弯曲通道中湍流的性质，设计了一个实验框架。该文报道了无渗流和无渗流的弯道内湍流的结构。随着向下的渗漏，近床层的雷诺剪切应力发生了明显变化，这表明了更多的动量传递。平均湍流和横向湍流强度分别增加了3.8–18.5％和4–10.6％，分别具有向下的渗流。计算Kolmogorov复杂度和Kolmogorov复杂度谱表明，外部区域具有较高的随机性，这可能与动量传递过多有关。在较低的流动深度\（\ left（{{\ text {z}} / {\ text {h}}} = 0.2 \ right）\），弯头外侧区域的横向速度随机性较高，约为25％，与折弯的中央和内部区域相比分别为38％。随着向下的渗漏，随机性增加，尤其是在外部区域。这种随机性的增加可能会报告弯曲外部的侵蚀作用。置换熵为研究横向速度时间序列的复杂行为提供了有益的手段，我们发现横向速度时间序列在外部流动区域中表现得更高。对于向下的渗流，整个弯道的熵均值增加。湍流的变化和渗流随机性的增加可能有助于了解渗流影响的弯曲冲积通道中的流量。