Flow structure and shear stress in the presence of both ice cover on water surface and leafless vegetation in channel bed

This study aimed to investigate the previously unexplored effects of ice cover and submerged vegetation on flow structure. Experiments were undertaken under both open channel and ice-covered flow conditions. The bed material consisted of three non-uniform sands. The findings revealed that when vegetation patches were present on the bed and an ice cover was present, the velocity profiles exhibited a distinctive pattern with two peak values. Turbulent kinetic energy (TKE) also exhibited two peaks, one above the vegetation bending height and another at the sheath section, with a decreasing trend towards the ice cover. Furthermore, quadrant analysis showed that when the flow surface is covered by an ice cover, the contributions of inward and outward events increased compared with those observed in an open channel flow. In most cases, these contributions surpassed the sweep and ejection events. The findings enhance our understanding of vegetation's response to diverse surface conditions and have practical implications for river management and environmental engineering.