Analytical models for bar patterns and braiding threshold

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Analytical models for bar patterns and braiding threshold


Hydromorphological models

Basic principles

Linearized fundamental equations for conservation of water mass and water flow momentum, time-averaged over all turbulent fluctuations, spatially averaged over water depth (2DH) or nor spatially averaged (3D). Linearized parameterized relation for effect of helical flow on bed shear stress direction. Linearized equilibrium sediment transport predictor or advection-relaxation equation for sediment transport. Linearized empirical relation for effect of sloping beds on sediment transport magnitude and direction. Linearized Exner equation for conservation of sediment mass.


Number of bars per cross-section, bar length, bar stability.


Related Pressures

Related Measures

Useful references

Selected software systems


Theoretical background

Blondeaux P. and Seminara G. (1983): Bed topography and instabilities in sinuous channels. In: River Meandering, Proc. Conf. Rivers 1983, New Orleans, Ed. C.M. Elliott, ASCE, 1984, pp.747-758.

Colombini M., Seminara G., Tubino M. (1987): Finite-amplitude alternate bars. J. Fluid Mech., 181, pp.213-232.

Crosato A. and Mosselman E. (2009): Simple physics-based predictor for the number of river bars and the transition between meandering and braiding, Water Resources Res., AGU, 45, W03424.

Struiksma N., Olesen K.W., Flokstra C., de Vriend H.J. (1985): Bed deformation in curved alluvial channels. J. Hydr. Res., IAHR, 23, (1), pp.57-79.

Sample applications