Bend theory of river meanders with spatial width variations

  title={Bend theory of river meanders with spatial width variations},
  author={Riccardo Luchi and Guido Zolezzi and Marco Tubino},
  journal={Journal of Fluid Mechanics},
  pages={311 - 339}
The present work revisits the classical, uniform-width bend theory with the aim to understand whether and how spatial width oscillations can affect the process of linear bend stability that initiates meander planform evolution. Although longitudinal oscillations of channel width are common along many meandering streams, little investigation of their properties and dynamic effects has been pursued so far. The theory therefore accounts for width variations as a geometrical forcing in a depth… 
Interaction between curvature-driven width oscillations and channel curvature in evolving meander bends
We study the morphodynamics of channel width oscillations associated with the planform development of river meander bends. With this aim we develop a novel planform evolution model, based on the
Modeling morphodynamic processes in meandering rivers with spatial width variations
Most morphodynamic models of river meandering assume spatially constant width; depending on the intensity of spatial width variations, different meandering styles actually exist, often associated
Spatial width oscillations in meandering rivers at equilibrium
In canaliform rivers channel width at bankfull stage is fairly uniform though, at bend apexes, it is typically smaller than at crossings. Conversely, in sinuous point bar rivers bankfull width peaks
A mathematical model for meandering rivers with varying width
The mathematical modeling of the long‐term evolution of meandering rivers needs an efficient computation of the flow field. Indeed, the estimate of the near bank velocity, needed to determine the
Coevolution of width and sinuosity in meandering rivers
Abstract This research implements a recently proposed framework for meander migration, in order to explore the coevolution of planform and channel width in a freely meandering river. In the model
The life of a meander bend: Connecting shape and dynamics via analysis of a numerical model
Analysis of bend‐scale meandering river dynamics is a problem of theoretical and practical interest. This work introduces a method for extracting and analyzing the history of individual meander bends
Flow and force-balance relations in a natural channel with bank vegetation
ABSTRACT The typical flow dynamics of meandering streams related to curvature and associated bed topography can be altered by stream width variations and vegetation. This paper presents laboratory


A nonlinear model for river meandering
We develop a nonlinear asymptotic theory of flow and bed topography in meandering channels able to describe finite amplitude perturbations of bottom topography and account for arbitrary, yet slow,
Planimetric instability of channels with variable width
We study the steady three-dimensional flow field and bed topography in a channel with sinusoidally varying width, under the assumptions of small-amplitude width variations and sufficiently wide
Downstream and upstream influence in river meandering. Part 1. General theory and application to overdeepening
Perturbations of channel geometry (like variations of channel curvature or channel width) in meandering rivers give rise to morphodynamic effects which display themselves through the development of
Bend theory of river meanders. Part 2. Nonlinear deformation of finite-amplitude bends
Meander bends typically show certain systematic deviations from simple Cartesian sinusoidal forms. Bends tend to be round and full, or ‘fat’, often to the point of possessing double-valued
Finite amplitude bed deformations in totally and partially transporting wide channel bends
We develop an analytic approach able to predict flow and bed topography in curved cohesionless wide channels. The novel feature of the present theory, compared with previous analytic approaches, is
Morphodynamic regime of gravel bed, single-thread meandering rivers
[1] This work attempts to link theoretical and experimental findings on the issue of two-dimensional morphodynamic influence with field data from natural single-thread rivers. Theoretical and
Weakly nonlinear theory of regular meanders
Flow and bed topography in a regular sequence of meanders is shown to be strongly influenced by nonlinear effects within a fairly wide range of aspect ratios of the channel and meander wavenumbers.
Downstream and upstream influence in river meandering. Part 2. Planimetric development
The exact solution of the problem of river morphodynamics derived in Part 1 is employed to formulate and solve the problem of planimetric evolution of river meanders. A nonlinear integrodifferential
Morphodynamic regime and long‐term evolution of meandering rivers
[1] In the present contribution we focus our attention on the long-term behavior of meandering rivers, a very common pattern in nature. This class of dynamical systems is driven by the coexistence of