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Determination of an LNT Regeneration Condition Based on a NOx Storage Fraction in a 2.2L Direct Injection Diesel Engine

2.2L 디젤 엔진에서 NOx 흡장률 기반 LNT 재생 조건 결정

  • Received : 2015.10.28
  • Accepted : 2016.01.13
  • Published : 2016.05.01

Abstract

This study was carried out to determine an optimal lean $NO_x$ trap (LNT) regeneration condition based on a $NO_x$ storage fraction. The LNT regeneration was performed by an in-cylinder post fuel injection method. A $NO_x$ storage fraction is defined by the ratio of current cumulated $NO_x$ amount in the LNT to the $NO_x$ storage capacity: 0 means empty and 1 fully loaded. In this study five engine operating conditions were chosen to represent the New European Driving Cycle. With various $NO_x$ storage fractions each engine operating condition, the LNT regeneration was executed and then $NO_x$ conversion efficiency, additional fuel consumption, CO and THC slip, peak catalyst temperature were measured. The results showed that there exist an optimal condition to regenerate the LNT, eg. 1500 rpm 6 bar BMEP with below 0.7 $NO_x$ storage fraction in this experimental constraint.

Keywords

Lean $NO_x$ trap;In-cylinder post fuel injection;$NO_x$ storage fraction;$NO_x$ conversion efficiency

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Acknowledgement

Supported by : 지식경제부