Author
YING, XINYA - University Of Mississippi | |
JORGESON, JEFF - Us Army Corp Of Engineers (USACE) | |
WANG, SAM - University Of Mississippi |
Submitted to: Engineering Applications of Computational Fluid Mechanics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/6/2008 Publication Date: 6/1/2009 Citation: Ying, X., Jorgeson, J., Wang, S.S.Y. 2009. Modeling dam-break flows using finite volume method on unstructured grid. Engineering Applications of Computational Fluid Mechanics. 3(2), 184-194. Interpretive Summary: Real-life surface water flows such as river flows and floods often take place over complicated terrain. In such situations, unstructured numerical models are more preferable as they are highly adaptive to complicated geometry. However, conventional unstructured models usually require complicated algorithms for treating source terms and second-order schemes for computing the intercell fluxes in order to gain numerically balanced and accurate solutions, which often results in an excessively long computational time. In this paper, authors proposed a simpler and more efficient finite volume method. The accuracy and significant improvement in computational efficiency of the newly developed model are demonstrated through several test problems that are commonly encountered in hydraulic engineering practice. This indicates that the present unstructured model is more attractive for simulating real-life surface water flows. Technical Abstract: Two-dimensional shallow water models based on unstructured finite volume method and approximate Riemann solvers for computing the intercell fluxes have drawn growing attention because of their robustness, high adaptivity to complicated geometry and ability to simulate flows with mixed regimes and discontinuities. Such models usually require complicated algorithms for treating source terms and second-order schemes for computing the intercell fluxes in order to gain numerically balanced and accurate solutions, which often results in an excessively long computational time. With a view of developing an accurate and efficient model for real-life applications, this paper proposed a finite volume method, which uses the first-order HLL approximate Riemann solver for computing intercell fluxes and employs the form of the momentum equations in which effects of pressure and gravity are included in one source term. Such treatment can easily eliminate numerical imbalance between source and flux terms without introducing complicated algorithms. The accuracy and improvement in computational efficiency of the newly developed model are demonstrated through several test problems that are commonly encountered in hydraulic engineering practice, including oblique hydraulic jump and dam-break flows. |