The ability to quantify particle mass and number concentrations in the exhaust stream of combustion engines during in-use operation is of critical importance for continuously monitoring and diagnosing the particulate matter removal efficiency of modern exhaust gas after-treatment systems. Extensive literature survey suggested a sensor operating on the diffusion-charging principle being optimally suited for particle measurements due to their proportional response towards particle surface area. This study was designed to determine and assess the possibility of quantifying particle emissions during on-road measurements using a prototype diffusion-charging type sensor. Such a sensor would not only allow for continuous monitoring capabilities of the exhaust particulate filters integrity, but moreover provide for a simplified tool to assess real-world particle number emissions to verify in-use emissions compliance of engines.
Evaluation of the sensor followed a three tier process, starting with fundamental sensor response analysis using a particle generator in order to develop and parameterize the underlying physical phenomena of the measurement principle. Next, examine the sensor in engine dynamometer experiments under controlled environment, and sampling from test vehicles during chassis dynamometer testing aimed at real-world like test conditions. Finally, the sensor was installed on vehicles while operated on the road over diverse driving conditions. This allowed for comparison to laboratory-grade measurement systems and the standard regulatory gravimetric particulate matter measurement method. The diffusion-charging type sensor employed in this study was observed to exhibit a response proportional to particle size Dp 1.09 and a measurement variability below 2% over consecutive tests. The sensor’s sensitivity allowed for distinguishing between Diesel particulate filter efficiencies due to soot cake layer build-up on the substrate walls. In summary, the study concluded that the diffusion-charging type sensor provided a viable method to quantify in-use particle number emissions.
|Commitee:||Ardanese, Raffaello, Clark, Nigel N., Li, Hailin, Shade, Benjamin C., Thompson, Gregory|
|School:||West Virginia University|
|Department:||Statler College of Engineering & Mineral Resources|
|School Location:||United States -- West Virginia|
|Source:||DAI-B 77/10(E), Dissertation Abstracts International|
|Keywords:||DPF filtration efficiency, Diffusion charging, In-line particle sensor, OBD, PN regulation|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be