Relaxation approximations to secondorder traffic flow models by highresolution schemes
Abstract
A relaxationtype approximation of secondorder nonequilibrium traffic models, written in conservation or balance law form, is considered. Using the relaxation approximation, the nonlinear equations are transformed to a semilinear diagonilizable problem with linear characteristic variables and stiff source terms with the attractive feature that neither Riemann solvers nor characteristic decompositions are in need. In particular, it is only necessary to provide the flux and source term functions and an estimate of the characteristic speeds. To discretize the resulting relaxation system, highresolution reconstructions in space are considered. Emphasis is given on a fifthorder WENO scheme and its performance. The computations reported demonstrate the simplicity and versatility of relaxation schemes as numerical solvers.
 Authors:
 School of Production Engineering and Management, Technical University of Crete, University Campus, Chania 73100, Crete (Greece)
 Publication Date:
 OSTI Identifier:
 22391112
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 1648; Journal Issue: 1; Conference: ICNAAM2014: International Conference on Numerical Analysis and Applied Mathematics 2014, Rhodes (Greece), 2228 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; APPROXIMATIONS; BALANCES; FLOW MODELS; FUNCTIONS; NONLINEAR PROBLEMS; PERFORMANCE; RELAXATION; RESOLUTION; SOURCE TERMS
Citation Formats
Nikolos, I.K., Delis, A.I., and Papageorgiou, M.. Relaxation approximations to secondorder traffic flow models by highresolution schemes. United States: N. p., 2015.
Web. doi:10.1063/1.4912741.
Nikolos, I.K., Delis, A.I., & Papageorgiou, M.. Relaxation approximations to secondorder traffic flow models by highresolution schemes. United States. doi:10.1063/1.4912741.
Nikolos, I.K., Delis, A.I., and Papageorgiou, M.. 2015.
"Relaxation approximations to secondorder traffic flow models by highresolution schemes". United States.
doi:10.1063/1.4912741.
@article{osti_22391112,
title = {Relaxation approximations to secondorder traffic flow models by highresolution schemes},
author = {Nikolos, I.K. and Delis, A.I. and Papageorgiou, M.},
abstractNote = {A relaxationtype approximation of secondorder nonequilibrium traffic models, written in conservation or balance law form, is considered. Using the relaxation approximation, the nonlinear equations are transformed to a semilinear diagonilizable problem with linear characteristic variables and stiff source terms with the attractive feature that neither Riemann solvers nor characteristic decompositions are in need. In particular, it is only necessary to provide the flux and source term functions and an estimate of the characteristic speeds. To discretize the resulting relaxation system, highresolution reconstructions in space are considered. Emphasis is given on a fifthorder WENO scheme and its performance. The computations reported demonstrate the simplicity and versatility of relaxation schemes as numerical solvers.},
doi = {10.1063/1.4912741},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1648,
place = {United States},
year = 2015,
month = 3
}

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