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Fast reliable simulations of secondary settling tanks in wastewater treatment with semi-implicit time discretization

Diehl, Stefan LU ; Farås, Sebastian LU and Mauritsson, Gustav (2015) In Computers & Mathematics With Applications 70(4). p.459-477
Abstract
The bio-kinetic and sedimentation processes of wastewater treatment plants can be modelled by a large system of coupled nonlinear ordinary and partial differential equations (ODEs and PDEs). The subprocess of continuous sedimentation, which contains concentration discontinuities, is modelled by a degenerate parabolic conservation PDE with spatially discontinuous coefficients. A spatial discretization of this PDE described in Bürger et al. (2013) results in a large system of method-of-lines ODEs for the entire plant and simulation can be performed by integration in time. In practice, standard time integration methods available in commercial simulators are often used. Shortages of such methods are here shown, such as the smearing of shock... (More)
The bio-kinetic and sedimentation processes of wastewater treatment plants can be modelled by a large system of coupled nonlinear ordinary and partial differential equations (ODEs and PDEs). The subprocess of continuous sedimentation, which contains concentration discontinuities, is modelled by a degenerate parabolic conservation PDE with spatially discontinuous coefficients. A spatial discretization of this PDE described in Bürger et al. (2013) results in a large system of method-of-lines ODEs for the entire plant and simulation can be performed by integration in time. In practice, standard time integration methods available in commercial simulators are often used. Shortages of such methods are here shown, such as the smearing of shock waves by Runge–Kutta methods and long execution times. A semi-implicit time discretization, which is described in detail, provides substantially shorter computational times and is more efficient than standard methods. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Nonlinear conservation PDE, Method-of-lines (MOL), Efficiency, Activated sludge process, Activated Sludge Model no. 1 (ASM1), Benchmark Simulation Model (BSM)
in
Computers & Mathematics With Applications
volume
70
issue
4
pages
459 - 477
publisher
Elsevier
external identifiers
  • wos:000359963200006
  • scopus:84937727750
ISSN
0898-1221
DOI
10.1016/j.camwa.2015.05.005
language
English
LU publication?
yes
id
7d58467f-9a4c-4964-8cb6-9687006c8845 (old id 5421965)
date added to LUP
2015-06-17 12:18:43
date last changed
2017-10-22 04:16:33
@article{7d58467f-9a4c-4964-8cb6-9687006c8845,
  abstract     = {The bio-kinetic and sedimentation processes of wastewater treatment plants can be modelled by a large system of coupled nonlinear ordinary and partial differential equations (ODEs and PDEs). The subprocess of continuous sedimentation, which contains concentration discontinuities, is modelled by a degenerate parabolic conservation PDE with spatially discontinuous coefficients. A spatial discretization of this PDE described in Bürger et al. (2013) results in a large system of method-of-lines ODEs for the entire plant and simulation can be performed by integration in time. In practice, standard time integration methods available in commercial simulators are often used. Shortages of such methods are here shown, such as the smearing of shock waves by Runge–Kutta methods and long execution times. A semi-implicit time discretization, which is described in detail, provides substantially shorter computational times and is more efficient than standard methods.},
  author       = {Diehl, Stefan and Farås, Sebastian and Mauritsson, Gustav},
  issn         = {0898-1221},
  keyword      = {Nonlinear conservation PDE,Method-of-lines (MOL),Efficiency,Activated sludge process,Activated Sludge Model no. 1 (ASM1),Benchmark Simulation Model (BSM)},
  language     = {eng},
  number       = {4},
  pages        = {459--477},
  publisher    = {Elsevier},
  series       = {Computers & Mathematics With Applications},
  title        = {Fast reliable simulations of secondary settling tanks in wastewater treatment with semi-implicit time discretization},
  url          = {http://dx.doi.org/10.1016/j.camwa.2015.05.005},
  volume       = {70},
  year         = {2015},
}