Figure 12. Flow separation in tidal meander bends according to Leeder & Bridges (1975). The normalized radius of curvature (\(\frac{R}{W_{Y}}\)) is plotted as a function of Froude number (Fr) for distinct tidal flow depth (\(Y\)) and velocity (\(U\)) at the apex of the studied meander bend. The parameter \(W_{Y}\) represents the effective bend width corresponding to different water depths (\(Y\)), whereasFr is calculated for different water depths \(Y\) and the corresponding uniform flow velocities \(U\), the latter being approximated by the depth-averaged velocity (DAV). Colors denote varying normalized water depths, computed as the ratio between instantaneous water depths and the maximum water depth (\(Y_{\max}\)) observed during the entire monitoring timespan. Filled dots denote below-bankfull water stages (\(Y\)<\(Y_{B}\), where \(Y_{B}\)is the bankfull depth), whereas empty squares highlight above-bankfull stages (\(Y\)>\(Y_{B}\)). Original data points from Leeder and Bridges (1975) are also reported using gray markers, along with their empirical line separating bends with and without flow separation.