A4.1 - Setup to eliminate the gas flow dependency of a hydrocarbon sensor for automotive exhaust applications

Event
AMA Conferences 2017
2017-05-30 - 2017-06-01
Nürnberg, Germany
Band
Proceedings Sensor 2017
Chapter
A4 - Gas Sensors I
Author(s)
G. Hagen, A. Harsch, R. Moos - University of Bayreuth (Germany)
Pages
84 - 86
DOI
10.5162/sensor2017/A4.1
ISBN
978-3-9816876-4-4
Price
free

Abstract

Recently, a thermoelectric hydrocarbon sensor was developed for application in exhaust gas atmospheres by using materials which are well-known in the exhaust and stable against poisoning or ageing and at high temperatures. The temperature difference, which is generated between a catalytic activated area during exothermic oxidation of hydrocarbons and an inert area of the sensor, is measured by a special screen-printed thermopile structure. As a matter of principle, this thermovoltage significantly depends on the mass flow of the exhaust. The present contribution helps to understand this cross-effect and proposes a possible setup for its avoidance. By installing the sensor in the correct position of a bypass-solution, the gas flow around the sensor is mostly free of turbulences. Now, the signal depends only on the hydrocarbon concentration and not on the gas flow.