Implementation of the Effectiveness-Ntu Methodology for Catalytic Converter Design

Paper #:
  • 980673

Published:
  • 1998-02-23
Citation:
Blanchet, S., Richmond, R., and Vaneman, G., "Implementation of the Effectiveness-Ntu Methodology for Catalytic Converter Design," SAE Technical Paper 980673, 1998, https://doi.org/10.4271/980673.
Pages:
15
Abstract:
Design of automotive catalytic converters is a complex process involving the optimization of many physical and chemical variables. Often, simple characteristics such as geometric surface area and space velocity are used to compare alternative designs. Unfortunately, these parameters do not account for all of the relative variables affecting emissions performance. The effectiveness-Ntu methodology, developed for heat exchanger design, can be extended to catalytic converter design through the heat and mass transfer analogy. This technique allows comparisons to include all physical variables affecting emissions performance. This paper presents Ntu-based, catalyst performance criteria for steady state and transient emissions and exhaust flow restriction. The theoretical analysis includes the effects of washcoat on cell geometry and, subsequently, on heat/mass-transfer performance. Additionally, the impact of chemical variables, such as PGM load, are coupled with the mass-transfer-limited analysis through a reaction resistance analogy. Experimental measurements of engine emissions and pressure drop support the theoretical results.
Access
Now
SAE MOBILUS Subscriber? You may already have access.
Buy
Select
Price
List
Download
$27.00
Mail
$27.00
Members save up to 40% off list price.
Share
HTML for Linking to Page
Page URL

Related Items

Training / Education
2013-02-20
Training / Education
2013-04-09