Stefan Diehl
Associate Professor in Applied Mathematics (Docent i
tillämpad matematik)
Centre
for Mathematical Sciences
Lund University/Lund Institute of Technology
P.O. Box 118
SE-221 00 Lund
SWEDEN
Room: 551A
Direct phone: +46 46 222 0920
Dept phone: +46 46 222 8537
Fax: +46 46 222 4010
E-mail: diehl@maths.lth.se
Miscellaneous (in
Swedish)
Min
docentföreläsning om modellering av trafikflöde,
september 2006 (3.1 Mb)
Jag har skrivit en bok Inledande geometri för högskolestudier (innehåll) som ges ut av Studentlitteratur.
Förslag på examensarbeten
Sedimentering av biologiskt slam – parameterkalibrering av PDESimulering av vattenreningsverk med ODE och PDETredimensionell rekonstruktion av tvådimensionell uppklippt sfärisk yta
Research
Interests
- non-linear
conservation laws and convection-diffusion equations with discontinuous
coefficients
- identification of constitutive relations in PDE models
- modelling,
simulation and control of the separation process continuous
sedimentation, which can be found in, for example, most wastewater
treatment plants, the mineral, pulp-and-paper, food and chemical
industries
- modelling,
simulation and control of the activated sludge process, which can
be found in most wastewater treatment plants
- other
applications, for example, traffic flow
Old stuff
Swe: En mycket kortfattad beskrivning i populär form av kontinuerlig sedimentering och min
doktorsavhandling (1995).
Lecture
notes containing an
introduction to the scalar conservation law (1996).
Doctoral thesis
Stefan Diehl: Conservation Laws with Application to
Continuous Sedimentation, Lund University, ISBN 91-628-1632-2 (1995)
Journal publications
If you are interested in a publication that you cannot
find in the links below, please send me an email.
- S.
Diehl: On scalar conservation laws with point source and discontinuous
flux function. SIAM
J. Math. Anal., 26(6):1425-1451, 1995. Submitted version.
- S.
Diehl: Scalar conservation laws with discontinuous flux function: I. The
viscous profile condition.Comm.
Math. Phys., 176:23-44, 1996. Submitted version.
- S. Diehl, Nils-Olof Wallin: Scalar conservation laws with discontinuous flux
function: II. On
the stability of the viscous profiles. Comm. Math. Phys., 176:45-71, 1996.
- S. Diehl: A
conservation law with point source and discontinuous flux function
modelling continuous sedimentation. SIAM J. Appl. Math., 56(2):388-419, 1996.
- U.
Jeppsson and S. Diehl: An evaluation of a dynamic model of the secondary
clarifier. Water Sci. Tech., 34(5-6):19-26, 1996.
- U.
Jeppsson and S. Diehl: On the modelling of the dynamic propagation of
biological components in the secondary clarifier. Water Sci. Tech., 34(5-6):85-92, 1996.
- S. Diehl: Dynamic
and steady-state behaviour of continuous sedimentation. SIAM J. Appl. Math., 57(4):991-1018, 1997.
- S. Diehl: Continuous sedimentation of multi-component particles.Math. Meth. Appl. Sci.,20:1345-1364, 1997.
- S. Diehl and U. Jeppsson: A model of the settler coupled to the biological
reactor. Water Res., 32(2):331-342, 1998.
- S. Diehl: On bondary conditions and solutions for ideal clarifier-thickener
units. Chem.
Eng. J., 80:119-133, 2000. (A conference talk in 1999.)
- S. Diehl: Operating charts for continuous sedimentation I: Control of steady
states. J.
Eng. Math., 41:117-144, 2001. (Final draft)
- S. Diehl: Operating charts for continuous sedimentation II: Step responses. J. Eng.
Math.,
53:139-185, 2005. (Final draft)
- S. Diehl: Operating charts for continuous sedimentation III: Control of step
inputs. J. Eng.
Math.,
54:225-259, 2006. (Final draft)
- S. Diehl: Estimation of the batch-settling flux function for an ideal
suspension from only two experiments. Chem.
Eng. Sci.,
62:4589-4601, 2007. http://dx.doi.org/10.1016/j.ces.2007.05.025
- S. Diehl: Operating charts for continuous sedimentation IV: Limitations for
control of dynamic behaviour. J. Eng.
Math., 60:249-264,
2008. (Final draft)
- S. Diehl: A regulator for continuous sedimentation in ideal
clarifier-thickener units. J. Eng.
Math. 60:265-291,
2008. (Final draft)
- S. Diehl: The solids-flux theory – confirmation and extension by using
partial differential equations. Water
Res.
42:4976-4988, 2008. http://dx.doi.org/10.1016/j.watres.2008.09.005
- S. Diehl: A uniqueness condition for nonlinear convection-diffusion equations
with discontinuous coefficients. J.
Hyperbolic Differential Equations, 6:127-159, 2009. (submitted
version)
- R.
Bürger, S. Diehl and I. Nopens: A consistent modelling
methodology for secondary settling tanks in wastewater treatment. Water Res. 45:2247-2260, 2011. http://dx.doi.org/10.1016/j.watres.2011.01.020
- S.
Diehl and S. Farås: Fundamental nonlinearities of the reactor-settler
interaction in the activated sludge process. To apper in Water Sci.
Tech.
- E. Torfs, R.
Bürger, S.
Diehl, S. Farås and I. Nopens: A reliable numerical method for secondary settling modelling. Comm. Appl. Biol. Sci. 77(1), 151-156, 2012.
- R.
Bürger, S.
Diehl, S. Farås and I. Nopens: On reliable and unreliable
numerical methods for the simulation of secondary settling tanks in
wastewater treatment. Computers Chem. Eng. 41:93-105, 2012
- S.
Diehl and S. Farås: A reduced-order ODE-PDE model for the activated
sludge process in wastewater treatment: 1. Classification and stability
of steady states. To appear in Math. Models Meth. Appl. Sci.
Conference
publications
- S. Diehl, G. Sparr and G. Olsson: Analytical and numerical
description of the settling process in the activated sludge operation. In R.
Briggs, editor, Instrumentation, Control and Automation of Water and Wastewater
Treatment and Transport Systems, pages 471-478. IAWPRC, Pergamon Press, 1990.
- U.
Jeppsson and S. Diehl: Validation of a robust model of continuous
sedimentation. Proc.
9th Forum for Applied Biotechnology (FAB), Med. Fac. Landbouww. Univ. Gent, 60/4b,
1995, pp 2403-2414.
- R.
Bürger, S. Diehl, S. Farås and I. Nopens: Simulations of the secondary settling process with consistent numerical methods.WATERMATEX 2011: 8th IWA Symposium on Systems Analysis and Integrated Assessment, San Sebastian, Spain, 2011.
- S.
Diehl and S. Farås: Fundamental nonlinearities of the reactor-settler
interaction in the activated sludge process. WATERMATEX 2011: 8th IWA
Symposium on Systems Analysis and Integrated Assessment, San Sebastian,
Spain, 2011.
- S. Diehl. Shock-wave behaviour of sedimentation in wastewater treatment:
a rich problem. Analysis for Science, Engineering and Beyond.
The
Tribute Workshop in Honour of Gunnar Sparr held in Lund, May 8-9,
2008. Åström, K.;
Persson, L.-E.; Silvestrov, S. D. (Eds.). Springer Proceedings in Mathematics, Vol. 6, 175–214, 2012.
Submitted manuscripts
- S.
Diehl and S. Farås: A reduced-order ODE-PDE model for the activated
sludge process in wastewater treatment: 2. Control of steady states
- R.
Bürger, S. Diehl, S. Farås, I. Nopens and E. Torfs: A consistent modelling
methodology for secondary settling tanks: A reliable numerical method