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Development of Emission Control Technology for Urban Bus Retrofit
Technical Paper
2000-01-0479
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Event:
SAE 2000 World Congress
Language:
English
Abstract
The EPA implemented the Urban Bus Retrofit/Rebuild (UBRR) Program for transit buses built before 1994 in an effort to lower the amount of PM emissions in densely populated urban areas. The objective of the program is to provide certified emission control technologies that reduce PM emissions from older buses by 25% or to below 0.1 g/bhp-hr. This paper reviews the development of a retrofit kit that has been certified under the UBRR program to meet the 0.1 g/bhp-hr PM emission requirements on DDC 6V92TA engines with both mechanical (MUI) and electronic (DDEC) fuel injection controls. The kit is a combination of specific and modified engine parts and a catalytic exhaust after-treatment device.
The kit replaces existing parts with a new camshaft, a uniquely configured cylinder kit and specified turbocharger, blower and injector. For the MUI engines the cam timing, injector height and fuel modulator are set at specific values to achieve the lowest possible PM level. For the DDEC engines, a specific engine control program and a timing offset key are used to fine-tune injection timing to minimize emission levels. An oxidation catalyst is used to provide additional PM reduction to meet the 0.1 g/bhp-hr emission level.
The retrofit technology was tested under the EPA Heavy-Duty Diesel transient FTP cycle. The retrofit kit development and performance test results are discussed. Field test results from buses with retrofit engines are also reviewed.
Authors
Citation
Conway, R., Chatterjee, S., and Windawi, H., "Development of Emission Control Technology for Urban Bus Retrofit," SAE Technical Paper 2000-01-0479, 2000, https://doi.org/10.4271/2000-01-0479.Also In
References
- “Urban Bus Rebuild Requirements” July 1 1998
- Brown K. Rideout G. “Urban Driving Cycle results of Retrofitted Diesel Oxidation Catalysts on Heavy Duty Vehicles” SAE 960134
- Green Edward “Low Emission Power Plant and Method of Making Same” 9 24 96
- Heywood, J. Internal Combustion Engine Fundamentals McGraw-Hill New York 1988 582
- 3 4
- Federal Register 61 75 April 17 1996