Investigation on the Performance of Diesel Oxidation Catalyst during Cold Start at Low Temperature Conditions

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

Abstract

Cold start is a critical operating condition for diesel engines because of the pollutant emissions produced by the unstable combustion and non-performance of after-treatment at lower temperatures. In this research investigation, a light-duty turbocharged diesel engine equipped with a common rail injection system was tested on a transient engine testing bed to study the starting process in terms of engine performance and emissions. The engine (including engine coolant, engine oil and fuel) was soaked in a cold cell at −7°C for at least 8 hours before starting the test. The engine operating parameters such as engine speed, air/fuel ratio, and EGR rate were recorded during the tests. Pollutant emissions (Hydrocarbon (HC), NOx, and particles both in mode of nucleation and accumulation) were measured before and after the Diesel Oxidation Catalyst (DOC). The results show that conversion efficiency of NOx was higher during acceleration period at −7°C start than the case of 20°C start. The reduction of NOx and Total Hydrocarbons (THC) by the DOC was less during the idle period at −7°C cold start. Most of the nucleation particles were removed in both 20°C and −7°C conditions. Meanwhile, the accumulation particles were only reduced during the acceleration period at −7°C start due to the deposits caused by thermophoresis.

Details

Original languageEnglish
Article number2014-01-2712
Number of pages9
JournalSAE Technical Paper 2014-01-2712
Publication statusPublished - 13 Oct 2014
EventSAE 2014 International Powertrain, Fuels & Lubricants Meeting - University of Birmingham, United Kingdom
Duration: 20 Oct 201424 Oct 2014