title: Comparative Study of Different Methods for Soot Sensing and Filter Monitoring in Diesel Exhausts.
abstract: Due to increasingly tighter emission limits for diesel and gasoline engines, especially concerning particulate matter emissions, particulate filters are becoming indispensable devices for exhaust gas after treatment. Thereby, for an efficient engine and filter control strategy and a cost-efficient filter design, reliable technologies to determine the soot load of the filters and to measure particulate matter concentrations in the exhaust gas during vehicle operation are highly needed. In this study, different approaches for soot sensing are compared. Measurements were conducted on a dynamometer diesel engine test bench with a diesel particulate filter (DPF). The DPF was monitored by a relatively new microwave-based approach. Simultaneously, a resistive type soot sensor and a Pegasor soot sensing device as a reference system measured the soot concentration exhaust upstream of the DPF. By changing engine parameters, different engine out soot emission rates were set. It was found that the microwave-based signal may not only indicate directly the filter loading, but by a time derivative, the engine out soot emission rate can be deduced. Furthermore, by integrating the measured particulate mass in the exhaust, the soot load of the filter can be determined. In summary, all systems coincide well within certain boundaries and the filter itself can act as a soot sensor.
authors.affiliation: Bayreuth Engine Research Center (BERC), Department of Functional Materials, University of Bayreuth, 95447 Bayreuth, Germany. funktionsmaterialien@uni-bayreuth.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Feulner
authors.affiliation: Bayreuth Engine Research Center (BERC), Department of Functional Materials, University of Bayreuth, 95447 Bayreuth, Germany. funktionsmaterialien@uni-bayreuth.de.
authors.forename: Gunter
authors.initials: G
authors.lastname: Hagen
authors.affiliation: Bayreuth Engine Research Center (BERC), Department of Functional Materials, University of Bayreuth, 95447 Bayreuth, Germany. funktionsmaterialien@uni-bayreuth.de.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Hottner
authors.affiliation: Bayreuth Engine Research Center (BERC), Department of Functional Materials, University of Bayreuth, 95447 Bayreuth, Germany. funktionsmaterialien@uni-bayreuth.de.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Redel
authors.affiliation: Bayreuth Engine Research Center (BERC), Department of Functional Materials, University of Bayreuth, 95447 Bayreuth, Germany. funktionsmaterialien@uni-bayreuth.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Müller
authors.affiliation: Bayreuth Engine Research Center (BERC), Department of Functional Materials, University of Bayreuth, 95447 Bayreuth, Germany. funktionsmaterialien@uni-bayreuth.de.
authors.forename: Ralf
authors.initials: R
authors.lastname: Moos
keywords: DPF; cavity perturbation; dosimeter; filter monitoring; integrating sensor; microwave; particulate matter; resistive soot sensor; soot; soot load determination