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Title: The shallow water equations as a hybrid flow model for the numerical and experimental analysis of hydro power stations

Abstract

The numerical analysis of hydro power stations is an important method of the hydraulic design and is used for the development and optimisation of hydro power stations in addition to the experiments with the physical submodel of a full model in the hydraulic laboratory. For the numerical analysis, 2D and 3D models are appropriate and commonly used.The 2D models refer mainly to the shallow water equations (SWE), since for this flow model a large experience on a wide field of applications for the flow analysis of numerous problems in hydraulic engineering already exists. Often, the flow model is verified by in situ measurements. In order to consider 3D flow phenomena close to singularities like weirs, hydro power stations etc. the development of a hybrid fluid model is advantageous to improve the quality and significance of the global model. Here, an extended hybrid flow model based on the principle of the SWE is presented. The hybrid flow model directly links the numerical model with the experimental data, which may originate from physical full models, physical submodels and in-situ measurements. Hence a wide field of application of the hybrid model emerges including the improvement of numerical models and the strong coupling ofmore » numerical and experimental analysis.« less

Authors:
;  [1]
  1. AG Regenerative Energien, Institut für Statik, TU Braunschweig, Beethovenstrasse 51, 38106 Braunschweig (Germany)
Publication Date:
OSTI Identifier:
22391122
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1648; Journal Issue: 1; Conference: ICNAAM-2014: International Conference on Numerical Analysis and Applied Mathematics 2014, Rhodes (Greece), 22-28 Sep 2014; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; FLOW MODELS; FLUIDS; NUMERICAL ANALYSIS; OPTIMIZATION; SINGULARITY; THREE-DIMENSIONAL CALCULATIONS; TWO-DIMENSIONAL CALCULATIONS; WATER

Citation Formats

Ostermann, Lars, and Seidel, Christian. The shallow water equations as a hybrid flow model for the numerical and experimental analysis of hydro power stations. United States: N. p., 2015. Web. doi:10.1063/1.4912784.
Ostermann, Lars, & Seidel, Christian. The shallow water equations as a hybrid flow model for the numerical and experimental analysis of hydro power stations. United States. doi:10.1063/1.4912784.
Ostermann, Lars, and Seidel, Christian. Tue . "The shallow water equations as a hybrid flow model for the numerical and experimental analysis of hydro power stations". United States. doi:10.1063/1.4912784.
@article{osti_22391122,
title = {The shallow water equations as a hybrid flow model for the numerical and experimental analysis of hydro power stations},
author = {Ostermann, Lars and Seidel, Christian},
abstractNote = {The numerical analysis of hydro power stations is an important method of the hydraulic design and is used for the development and optimisation of hydro power stations in addition to the experiments with the physical submodel of a full model in the hydraulic laboratory. For the numerical analysis, 2D and 3D models are appropriate and commonly used.The 2D models refer mainly to the shallow water equations (SWE), since for this flow model a large experience on a wide field of applications for the flow analysis of numerous problems in hydraulic engineering already exists. Often, the flow model is verified by in situ measurements. In order to consider 3D flow phenomena close to singularities like weirs, hydro power stations etc. the development of a hybrid fluid model is advantageous to improve the quality and significance of the global model. Here, an extended hybrid flow model based on the principle of the SWE is presented. The hybrid flow model directly links the numerical model with the experimental data, which may originate from physical full models, physical submodels and in-situ measurements. Hence a wide field of application of the hybrid model emerges including the improvement of numerical models and the strong coupling of numerical and experimental analysis.},
doi = {10.1063/1.4912784},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1648,
place = {United States},
year = {Tue Mar 10 00:00:00 EDT 2015},
month = {Tue Mar 10 00:00:00 EDT 2015}
}
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  • In this paper, the authors report their work on applying Krylov iterative methods, accelerated by parallelizable domain-decomposed (DD) preconditioners, to the solution of nonsymmetric linear algebraic equations arising from implicit time discretization of a finite element model of the shallow water equations on a limited-area domain. Two types of previously proposed DD preconditioners are employed and a novel one is advocated to accelerate, with post-preconditioning, the convergence of three popular and competitive Krylov iterative linear solvers. Performance sensitivities of these preconditioners to inexact subdomain solvers are also reported. Autotasking, the parallel processing capability representing the third phase of multitasking librariesmore » on CRAY Y-MP, has been exploited and successfully applied to both loop and subroutine level parallelization. Satisfactory speedup results were obtained. On the other hand, automatic loop-level parallelization, made possible by the autotasking preprocessor, attained only a speedup smaller than a factor of two. 39 refs., 2 figs., 6 tabs.« less
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