THERMAL BEHAVIOR OF AN EXHAUST GAS CATALYTIC CONVERTOR

A combined theoretical-experimental study of the thermal behavior of a catalytic convertor for controlling air-polluting emissions in the exhaust gases of motor vehicles consisted of devising a numerical solution to a mathematical model describing the transient temperature profiles in the convertor and experimentally measuring the flow rates and temperatures of the exhaust gases to be treated. Data were obtained for two vehicles operating on a chassis dynamometer over the driving regime prescribed by the California Motor Vehicle Pollution Control Board for exhaust device testing. The measured exhaust gas data and the mathematical model were combined to predict the dynamic behavior of a catalytic convertor for various sets of conditions. Excellent agreement was obtained when predicted temperature profiles were compared with measured profiles in an experimental convertor. The study enabled a quantitative evaluation of the restrictions imposed on the usefulness of the catalytic convertor approach to reduce air pollution due to warm-up problems. © 1968, American Chemical Society. All rights reserved.