Idle Emissions from Heavy-Duty Diesel Vehicles: Review and Recent Data

• Published in: Journal of the Air & Waste Management Association (1995) Vol. 56; no. 10; pp. 1404 - 1419
• Main Authors: Khan, ABM S., Clark, Nigel N., Thompson, Gregory J., Wayne, W. Scott, Gautam, Mridul, Lyon, Donald W., Hawelti, Daniel
• Format: Journal Article
• Language: English
• Published: Pittsburgh, PA Taylor & Francis Group 01.10.2006; Air & Waste Management Association; Air and Waste Management Association; Taylor & Francis Ltd
• Subjects: Air conditioning; Air Pollutants - analysis; Applied sciences; Atmospheric pollution; Carbon dioxide; Carbon Dioxide - analysis; Carbon Monoxide - analysis; Data collection; Emissions; Emissions (Pollution); Energy policy; Environmental aspects; Environmental Monitoring; Exact sciences and technology; Gasoline; Hydrocarbons - analysis; Lubrication and lubricants; Monetary incentives; Motor Vehicles; Nitrogen Oxides - analysis; Particulate Matter - analysis; Pollution; Repair & maintenance; Studies; Vehicle Emissions - analysis; Vehicles; United States; Air conditioning; Carbon dioxide; Compressor; Fuel consumption; Diesel engine; Combustion; Motor vehicle; Pollutant emission; Fan; Lorry; Aerosols; Database; Air pollution; Road traffic
• ISSN: 1096-2247; 2162-2906
• DOI: 10.1080/10473289.2006.10464551

Heavy-duty diesel vehicle idling consumes fuel and reduces atmospheric quality, but its restriction cannot simply be proscribed, because cab heat or air-conditioning provides essential driver comfort. A comprehensive tailpipe emissions database to describe idling impacts is not yet available. This paper presents a substantial data set that incorporates results from the West Virginia University transient engine test cell, the E-55/59 Study and the Gasoline/Diesel PM Split Study. It covered 75 heavy-duty diesel engines and trucks, which were divided into two groups: vehicles with mechanical fuel injection (MFI) and vehicles with electronic fuel injection (EFI). Idle emissions of CO, hydrocarbon (HC), oxides of nitrogen (NO x ), particulate matter (PM), and carbon dioxide (CO 2 ) have been reported. Idle CO 2 emissions allowed the projection of fuel consumption during idling. Test-to-test variations were observed for repeat idle tests on the same vehicle because of measurement variation, accessory loads, and ambient conditions. Vehicles fitted with EFI, on average, emitted [~20 g/hr of CO, 6 g/hr of HC, 86 g/hr of NO x , 1 g/hr of PM, and 4636 g/hr of CO 2 during idle. MFI equipped vehicles emitted ~35 g/hr of CO, 23 g/hr of HC, 48 g/hr of NO x , 4 g/hr of PM, and 4484 g/hr of CO 2 , on average, during idle. Vehicles with EFI emitted less idleCO, HC, and PM, which could be attributed to the efficient combustion and superior fuel atomization in EFI systems. Idle NO x , however, increased with EFI, which corresponds with the advancing of timing to improve idle combustion. Fuel injection management did not have any effect on CO 2 and, hence, fuel consumption. Use of air conditioning without increasing engine speed increased idle CO 2 , NO x , PM, HC, and fuel consumption by 25% on average. When the engine speed was elevated from 600 to 1100 revolutions per minute, CO 2 and NO x emissions and fuel consumption increased by >150%, whereas PM and HC emissions increased by ~100% and 70%, respectively. Six Detroit Diesel Corp. (DDC) Series 60 engines in engine test cell were found to emit less CO, NO x , and PM emissions and consumed fuel at only 75%of the level found in the chassis dynamometer data. This is because fan and compressor loads were absent in the engine test cell.