TU Darmstadt / ULB / TUbiblio

A Semi-Implicit Semi-spectral Primitive Equation Model for Lake Circulation Dynamics and Its Stability Performance

Wang, Yongqi and Hutter, Kolumban (1998):
A Semi-Implicit Semi-spectral Primitive Equation Model for Lake Circulation Dynamics and Its Stability Performance.
In: Journal of Computational Physics, Elsevier Science, pp. 209-241, 139, (1), ISSN 0021-9991,
DOI: 10.1006/jcph.1997.5850,
[Online-Edition: http://www.sciencedirect.com/science/article/pii/S0021999197...],
[Article]

Abstract

We present a three-dimensional numerical model for the shallow water equations, suitable for determining the wind driven currents in homogeneous and stratified lakes. The model is based on the semispectral primitive equation model (SPEM) originally developed by Haidvogelet al.; however, because of the relatively small water depths of inland lakes in comparison to the ocean, the explicit integration technique, employed in SPEM, requires excessively small time steps which lead to very long integration times. In this paper a semi-implicit temporal integration scheme is proposed with the aid of which time integrations through realistic time spans for inland lakes become economical. By means of a large number of test runs in which the time step, the mesh size, and the austausch coefficients are changed and the numerical stability and the convergence performances of the code are determined. Moreover, the new semi-implicit SPEM is tested as to whether it is now capable to predict or reproduce physically relevant processes that are commonly observed by physical limnologists. To this end, computational results for a homogeneous and stratified rectangle and Lake Constance are presented.

Item Type: Article
Erschienen: 1998
Creators: Wang, Yongqi and Hutter, Kolumban
Title: A Semi-Implicit Semi-spectral Primitive Equation Model for Lake Circulation Dynamics and Its Stability Performance
Language: English
Abstract:

We present a three-dimensional numerical model for the shallow water equations, suitable for determining the wind driven currents in homogeneous and stratified lakes. The model is based on the semispectral primitive equation model (SPEM) originally developed by Haidvogelet al.; however, because of the relatively small water depths of inland lakes in comparison to the ocean, the explicit integration technique, employed in SPEM, requires excessively small time steps which lead to very long integration times. In this paper a semi-implicit temporal integration scheme is proposed with the aid of which time integrations through realistic time spans for inland lakes become economical. By means of a large number of test runs in which the time step, the mesh size, and the austausch coefficients are changed and the numerical stability and the convergence performances of the code are determined. Moreover, the new semi-implicit SPEM is tested as to whether it is now capable to predict or reproduce physically relevant processes that are commonly observed by physical limnologists. To this end, computational results for a homogeneous and stratified rectangle and Lake Constance are presented.

Journal or Publication Title: Journal of Computational Physics
Volume: 139
Number: 1
Publisher: Elsevier Science
Uncontrolled Keywords: semi-implicit; semispectral; stability; convergence; lake circulation; limnology; oscillation
Divisions: 16 Department of Mechanical Engineering > Fluid Dynamics (fdy)
16 Department of Mechanical Engineering
Date Deposited: 30 Aug 2011 14:33
DOI: 10.1006/jcph.1997.5850
Official URL: http://www.sciencedirect.com/science/article/pii/S0021999197...
Additional Information:

doi:10.1006/jcph.1997.5850

Export:
Suche nach Titel in: TUfind oder in Google

Optionen (nur für Redakteure)

View Item View Item