Abstract
Intake throttling has been verified as an effective approach to increase the exhaust temperature of diesel engines, which could benefit the catalytic efficiency aftertreatment. To better understand the influence of intake throttling on the combustion characteristics and exhaust emissions of light-duty diesel engines operating under idle mode, a light-duty diesel engine was experimentally investigated. This study is a follow-on to previous studies on the effect of throttling on light-duty diesel engine exhaust temperatures and emissions. Tests were conducted at a fixed idle speed of 1100 rpm, and the throttle position and intake manifold air pressure (MAP) were varied. The in-cylinder pressure, pressure rise rate, heat release rate (HRR), in-cylinder temperature, exhaust temperature, and regular gaseous emissions were analyzed. The results indicated that under the influence of intake throttling, the MAP decreased from 101 kPa under wide-open-throttle (WOT) conditions to 52.5 kPa under the heaviest throttling conditions, and the exhaust temperature increased from 100 °C to 200 °C, with a fuel penalty associated with the increase in the pumping indicated mean effective pressure (IMEP). The in-cylinder pressure continuously declined with decreasing MAP, while the HRR generally increased with increasing MAP. Under WOT conditions, the ignition delay decreased, while the combustion duration decreased under heavier throttling conditions. The in-cylinder temperature with throttling was higher than that under WOT conditions, and after post-injection treatment, the in-cylinder temperature exhibited an increasing trend with decreasing MAP. The CO2, CO, NOx, and HC emissions increased with increasing throttling amounts.
Funder
Project of the Guangdong Education Department
High-Level Personnel Special Fund of the Guangdong Polytechnic of Industry and Commerce
Driverless and Vehicle-road collaboration Research & Innovation Team
China Scholarship Council
Subject
Energy (miscellaneous),Energy Engineering and Power Technology,Renewable Energy, Sustainability and the Environment,Electrical and Electronic Engineering,Control and Optimization,Engineering (miscellaneous),Building and Construction
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