Topics in Catalysis

, Volume 56, Issue 1–8, pp 483–488 | Cite as

In-Operation Monitoring of the Soot Load of Diesel Particulate Filters: Initial Tests

  • Markus Feulner
  • Gunter Hagen
  • Andreas Piontkowski
  • Andreas Müller
  • Gerhard Fischerauer
  • Dieter Brüggemann
  • Ralf MoosEmail author
Original Paper


Diesel particulate filters (DPF) are indispensable parts of modern automotive exhaust gas aftertreatment systems due to the stringent emissions legislation. For a fuel-efficient control strategy, it would be beneficial to determine directly and in-operation their actual trapped soot mass. Two novel approaches—based on the electrical conductivity of trapped soot particles—emerged recently. By measuring the electrical resistance between different single walls inside the filter, the soot load is determined with local resolution. The microwave-based technique is a contactless approach that gives an integral value depending on the soot mass in the DPF. We present investigations on loading and regeneration of DPFs in a dynamometer test bench applying both methods. The results are compared with each other and correlated with the differential pressure and the soot mass. Especially the microwave-based technique has a potential for serial application.


Cavity perturbation Microwave Radio frequency (RF) Soot conductivity Diesel particulate filter (DPF) Soot and ash load 



The authors R.M. and G.F. are indebted to the German Research Foundation (DFG) for financial support under grant number MO 1060/6-2 and FI 956/3-2, respectively.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Markus Feulner
    • 1
  • Gunter Hagen
    • 1
  • Andreas Piontkowski
    • 1
  • Andreas Müller
    • 1
  • Gerhard Fischerauer
    • 1
  • Dieter Brüggemann
    • 1
  • Ralf Moos
    • 1
    Email author
  1. 1.Bayreuth Engine Research Center (BERC)BayreuthGermany

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