고속응답 CO₂ 분석기의 제작 및 이를 이용한 SI엔진에서의 실시간 배기가스 분석에 관한 연구

Abstract

A fast-response CO₂ analyzer has been developed for measuring the CO₂ concentration during transient condition of a SI engine. The analyzer consists of the non-dispersive infrared absorption method, electrical chopping system and water cooling system. The analyzer has good repeatability, linearity and permissible drift characteristic. Besides, it showed 18ms of a response to measure the CO₂ concentration. The fast-response CO₂ analyzer was applied to a single cylinder SI engine and the CO₂ emission was examined during engine start. Simultaneously, the standard exhaust gas analyzer, which has slow response time, was used for confirming the accuracy of the exhaust gas analysis using the fast-response CO₂ analyzer. The developed analyzer showed much faster responsive characteristic than that of a standard analyzer and made cycle by cycle exhaust gas analysis possible. The transient engine operating characteristics will be estimated from the CO₂ concentration of engine-out emissions and engine operating variables.