ISSN:
0271-2091
Keywords:
St. Venant equations
;
Hyperbolic system
;
Characteristic-dissipative-Galerkin
;
Taylor-Galerkin
;
Least squares finite element
;
Engineering
;
Engineering General
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Finite element schemes for hyperbolic systems are applied to the St. Venant equations for one-dimensional, unsteady, open channel flow. The comparative performances of the characteristic-dissipative-Galerkin, Taylor-Galerkin and least squares finite element schemes are assessed by means of linear Fourier analysis and solution of idealized non-linear wave propagation problems. Of particular interest is the behaviour of these schemes for the regressive wave component in both subcritical and supercritical flows. To assess the quality of the basic solution, the methods are compared without any additional artificial diffusion or shock-capturing formulations. The balanced treatment of both wave components in the characteristic-dissipative-Galerkin method is illustrated. Also, the method displays little sensitivity to parameters variations. The Taylor-Galerkin scheme provides good solutions, although oscillations due to wave dispersion and minimal diffusion of the regressive wave are displayed. Also, this method is somewhat sensitive to the time step increment. The least squares method is considered unsuitable for unsteady, open channel flow problems owing to its inability to propagate a regressive wave in a supercritical flow.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/fld.1650200202
