Page 264 - Methods For Monitoring And Diagnosing The Efficiency Of Catalytic Converters A Patent - oriented Survey
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246 Methods for Monitoring and Diagnosing the Eeciency of Catalytic Converters
interpolation for the measured distribution of the temperature (see fig.
104b), or
c) locating a maximum temperature along the measurement path and
defining a maximum temperature location; determining an interval along
the measurement path around the maximum temperature location within
which the temperature deviates by less than a predetermined limit value
fiom the maximum value at the maximum temperature location, and
defining a boundary of the reaction zone
4) determining the degree of degradation of a catalytic converter by using the location of the
reaction zone with respect to the measurement path as a measure of the degree of
degradation.
As shown in fig. 104 and fig. 105, the more downstream of the inlet end of the catalytic
converter the reaction zone appears the more degraded the catalytic converter is.
Fig. 105 (from DE4038829)
The method of W09314305 (1993) refers to the monitoring the condition of an auxiliary
(light-off) catalytic converter installed upstream of a main catalytic converter (fig. 106) and
comprises the steps of:
