Turbulence Characteristics in Mild and Steep Entrance Slopes of Pool-Riffle Sequences

This study investigates the distributions of velocity and Reynolds stress in an artificial pool-riffle sequence for two entrance slopes 5° 20° a laboratory compares results with similar gravel-bed river central Iran. Quadrant analysis is applied to find out contributions different events on turbulent flow structures. At slope 5°, distribution follows exponential trend without separation, but 20°, indicates S-shaped pattern separation. Variation does not influence convex form (RS) distribution, it influences location maximum value RS separation zone length. The reveal that outward ejection are dominant both field settings. sweep displays decreasing from near bed toward water surface, however, contribution increasing surface. agreement between will help engineers better manage complex fluvial processes. Bursting process depend aspect ratio same pool slope. bursting encouraging restoration rivers cost projects.