Research

Oxidation Catalyst Studies on a Diesel Engine


Reference:

Ye, S., 2010. Oxidation Catalyst Studies on a Diesel Engine. Thesis (Doctor of Philosophy (PhD)). University of Bath.

Related documents:

[img]
Preview
PDF (UnivBath_PhD_2010_S_Ye.pdf) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (29MB) | Preview

    Abstract

    In this thesis, the experimental test facilities consisted of a well instrumented live Ford 2.0 litre turbocharged diesel engine connected to a specially made exhaust can, which contained a diesel oxidation catalyst (DOC). Experiments were performed on DOCs, which were specially prepared by Johnson Matthey, and had thermocouples mounted in their walls to measure axial temperature profiles. These DOCs consisted of a Pt catalyst dispersed in an alumina washcoat on a cordierite monolith supports, and were representative of a commercial application. Experiments were performed on Full-scale DOCs (o.d. = 106 mm, length = 114 mm), and also on Thin-slice DOCs (length = 5 and 10 mm), which generate some interesting data, and enabled a technique that is normally only used in laboratory bench-top experiments to be applied to a live engine. A number of different methodologies were developed based on (a) the operation of the engine at pseudo-steady-state operating conditions, and (b) transient experiments (e.g. a pulse of CO was injected into the exhaust gas just before the DOC). For example, it was shown how experiments on a live engine can be used to explore: (a) the hysteresis between light-off and extinction curves, (b) how catalyst temperature rise during warm-up of a DOC, (c) the promotion effect that hydrogen has on the conversion of CO, (d) the extent of competition for active catalytic sites, e.g. between CO, THCs, propane or hydrogen. The main findings are: (a) the hysteresis between light-off and extinction curves are mainly caused by CO inhibition, (b) the promotion effect of hydrogen on CO oxidation is largely attributed to thermal effect, (c) LHHW form rate expression is not adequate for catalytic converter modelling under transient conditions, (d) the competition for active catalytic sites is not apparent at the test conditions performed in this thesis. Moreover, a number of case studies were also used to illustrate how the experimental results/techniques developed in this thesis, may be used to support modelling studies. iii

    Details

    Item Type Thesis (Doctor of Philosophy (PhD))
    CreatorsYe, S.
    Uncontrolled Keywordsexperimental studies, diesel oxidation catalyst, promotion effect of hydrogen, catalyst light-off
    DepartmentsFaculty of Engineering & Design > Mechanical Engineering
    Publisher StatementUnivBath_PhD_2010_S_Ye.pdf: © The Author
    StatusUnpublished
    ID Code23886

    Export

    Actions (login required)

    View Item

    Document Downloads

    More statistics for this item...