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Differences in Pre- and Post-Converter Lambda Sensor Characteristics
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English
Abstract
The two characteristics of wide-range air/fuel ratio sensors when located in front of and behind a three-way catalytic converter are investigated. Input as well as output gas concentration measurements and sensor readouts are presented. Behind a new converter almost no oxygen can be measured for rich air/fuel ratios.
The wide-range sensor's signal is sensitive to changes in the gas composition when keeping the air/fuel ratio constant at a rich value. Since the gas compositions up- and down-stream of the converter differ, the sensor signals are not identical for the same rich air/fuel ratio before and after the converter.
The various diffusion coefficients of the exhaust gas species flowing through the porous coating of the sensor combinded with the different up- and downstream gas compositions are responsible for the different sensor characteristics.
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Citation
Germann, H., Taglaiferri, S., and Geering, H., "Differences in Pre- and Post-Converter Lambda Sensor Characteristics," SAE Technical Paper 960335, 1996, https://doi.org/10.4271/960335.Also In
References
- Takeushi T. Igarashi I. Limiting Current Type Oxygen Sensor Chemical Sensor Technology 1 79 95 Kodansha Tokyo & Elsevier Amsterdam 1988
- Atkins P. W. Physical Chemistry Fourth Oxford University Press Oxford 1990
- Onder C. H. Geering H. P. Model-Based Multivariable Speed and Air-to-Fuel Ratio Control of an SI-Engine SAE technical paper 930859 Electronic Engine Controls, SAE special publication SP-955 Detroit 1993
- Padeste L. Three-Way Catalysts in a Hybrid Drive System: Experimental Study and Kinetic Modelling Zurich 1994
- Hepburn J. S. Dobson D. A. et al. A Review of the Dual Oxygen Sensor Method for OBD-II Catalyst Efficiency Monitoring SAE technical paper 942057 1994
- Germann H. Onder C. H. Geering H. P. Fast Gas Concentration Measurements for Model Validation of Catalytic Converters SAE technical paper 950477 1995
- Shafai E. Roduner C. Geering H. P. Indirect Adaptive Control of a Three-Way Catalyst SAE technical paper SAE 96 International Congress Detroit 1996