# An amplitude equation for the non-linear analysis of river beds

* R.M.J. Schielen *

* Delft Hydraulics *

* P.O. box 152 *

* 8300 AD Emmeloord *

* The Netherlands *

* Keywords: river bed *

## Abstract

An amplitude equation for weak non-linear interactions of waves is derived
in order to describe the time and spatial evolution of a so-called alternate
bar pattern that arises, in auspicious conditions, on a river bed.
The coefficients of the equation are determined in an asymptotic expansion
of the drag coefficient, which is small in natural circumstances. This
expansion has the advantage that the influence of the model parameters
on the amplitude equation can be seen immediately.
* Computer Algebra in Industry *
Edited by A.M. Cohen © 1993 John Wiley & Sons Ltd

Reproduced by permission of John Wiley & Sons Ltd, 1995

** Go to:**

Applications

*Computer Algebra in Industry*

webmaster@can.nl

Last Update: June 24, 1997.