Topics in Catalysis

, Volume 60, Issue 3–5, pp 374–380 | Cite as

Influencing Parameters on the Microwave-Based Soot Load Determination of Diesel Particulate Filters

  • Markus Feulner
  • Florian Seufert
  • Andreas Müller
  • Gunter Hagen
  • Ralf Moos
Original Paper


Diesel Particulate Filters (DPF) are an essential part of today’s diesel exhaust gas aftertreatment systems. For an effective filter regeneration strategy, the precise knowledge of the actual trapped soot mass is essential. Besides the state-of-the-art technology of determining the soot load via pressure drop and/or model-based, a microwave-based method enables direct and in situ soot load detection. Thereby, an electric field is impressed into the filter housing and the power transmission is measured, which correlates with the soot load. In this study, influencing parameters, especially temperature and humidity, are examined and compared to the sensitivity towards soot accumulation. Measurements were conducted in a laboratory test bench with a filter-core, which had been previously loaded with soot in an engine dynamometer. While humidity does not have a notable effect, the influence of temperature needs to be considered for real world application. Finally, a complete filter regeneration of the DPF-core in the laboratory test bench could be monitored with the microwave-based system. The carbon balance-derived burned soot mass coincides very well with the microwave derived transmission parameter.


Diesel particulate filter (DPF) On-board diagnostics Exhaust gas aftertreatment Microwave Cavity perturbation 



The author R.M is indebted to the German Research Foundation (DFG) for financial support under Grant Number MO 1060/6-2.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Markus Feulner
    • 1
  • Florian Seufert
    • 1
  • Andreas Müller
    • 1
  • Gunter Hagen
    • 1
  • Ralf Moos
    • 1
  1. 1.Department of Functional Materials, Bayreuth Engine Research Center (BERC), Zentrum für Energietechnik (ZET)University of BayreuthBayreuthGermany

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