Development of the Low-Emission GE-7FDL High-Power Medium-Speed Locomotive Diesel Engine

Abstract

This paper summarizes the technical development of the low-emission GE-7FDL series locomotive diesel engine. The development focused on reducing the engine exhaust NOx emission significantly while reducing and curbing other visible and nonvisible emissions with minimal adverse impact on the engine fuel efficiency and minimal changes to the engine system and components. Concepts were analyzed, and were investigated using a single-cylinder 7FDL research engine. A low-emission 16-cylinder 7FDL engine and a GE locomotive prototype were built and tested for performance demonstration, function evaluation, and design optimization. The GE low-emission 7FDL engines and locomotives have been in production. The newly developed low-emission locomotive engine meets the EPA Tier-0 levels without fuel efficiency penalty. This was accomplished with minimal changes to the engine system and components. The desired engine reliability performance is retained. The engines are interchangeable with the preceding 7FDL baseline models, and the upgrade of the existing baseline engines to the low-emission version is facilitated.

A retrospective assessment of the costs of EPA’s 1998 Locomotive Emission Standards

“…Two other technologies that were used to meet Tier 0 requirements were increasing the compression ratio and modifying the cylinder liner and piston rings to reduce lubricating oil consumption. EPA had expected compression ratio changes to be introduced for compliance with Tier 1, but GE did so for Tier 0 as well (Chen, Flynn, Gallagher, & Dillen, 2003).…”

“…Rather, they were likely used to minimize the loss in fuel economy from retarding injection timing to meet the NOx standards. In addition, EF&EE reports that new Tier 0 locomotives (Models C and E) used split cooling (Uzkan & Lenz, 1999), increased compression ratios, and combustion chamber design, and Chen et al (2003) comment in their conclusions that the same technology package can also be used to upgrade baseline engines to the same standards. As with EFI, EF&EE expects that it was not strictly necessary to add split cooling in order to meet the standards.…”

Air pollutant emissions from the development, production, and processing of Marcellus Shale natural gas

“…Therefore, emission factors for the 2009 inventory were taken from the EPA's AP-42 (EPA, 2011a) and literature data for similarly sized engines used in diesel-electric locomotives and diesel generators (e.g., Shah et al, 2006;Sawant et al, 2007;Chen et al, 2003). The NONROAD model (EPA, 2008) was not used to estimate emission factors because it estimates point values and not distributions.…”

Experimental investigations of comparative performance, emission and combustion characteristics of a cottonseed biodiesel-fueled four-stroke locomotive diesel engine

“…All research reported on locomotive engines has evaluated the engine at pre-determined notches. 12–17 Accordingly, engine performance, emissions and combustion measurements in the present research is also carried out on these nine pre-determined engine notches. The experiments were performed three times for each engine operating point and the average reading was used for further data analysis.…”