This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Emissions Correlation Between a Partial-Flow Diluter and The Full-Flow Constant Volume Sampler (CVS) for a Heavy-Duty Vehicle Under Steady-State Operation
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 24, 2005 by SAE International in United States
Annotation ability available
The California Air Resources Board (CARB) examined the performance of a Partial Flow Sampling System (PFSS) against a reference Constant Volume Sampling (CVS) system in measuring emissions from a heavy-duty vehicle (HDV) during dynamometer testing at CARB's Stockton Heavy-Duty Emissions Laboratory (SL). The SL PFSS system is a Sierra BG-2 system that uses flow-based (rather than CO2-based) dilution. The CVS system uses the University of California, Riverside's (UCR) Mobile Emissions Laboratory (MEL). The test vehicle was a 2000 model-year HD tractor powered by a CAT C-15 engine. Exhaust samples were collected simultaneously with the SL and MEL systems and analyzed for total particulate matter (PM), oxides of nitrogen (NOx), carbon dioxide (CO2), carbon monoxide (CO), and total hydrocarbons (THC). The samples were taken during steady-state vehicle operation. Each test mode was repeated seven times in each of two patterns: consecutive and sequential. The test protocols used by Southwest Research Institute (SwRI) in their benchmark assessment of the performance of PFSS relative to the CVS were followed. R2 values of results for SL and the MEL were 0.92 or better. The comparison for PM measurements returned an R2 of 0.98. A systematic bias high of PFSS results relative to CVS results was detected. Percent differences in SL average results relative to MEL were mode and pollutant dependent, and on the order of 15%. Some suspect parameters, such as flow rate measurements, will be the subject of further investigation. Most importantly, a simplified low-cost alternative to the CVS for examining PM emissions from existing in-use HDVs using a chassis dynamometer was demonstrated. Although, some differences were note during modal analysis, our findings add to previous evidence that suggests statistical consistency between the two approaches for steady state testing.
- Alberto Ayala - California Air Resources Board
- Donald J. Chernich - California Air Resources Board
- Tao Huai - California Air Resources Board
- Kent C. Johnson - University of California, Riverside Department of Chemical and Environmental Engineering College of Engineering, Center for Environmental Research and Technology
- J. Wayne Miller - University of California, Riverside Department of Chemical and Environmental Engineering College of Engineering, Center for Environmental Research and Technology
CitationAyala, A., Chernich, D., Huai, T., Johnson, K. et al., "Emissions Correlation Between a Partial-Flow Diluter and The Full-Flow Constant Volume Sampler (CVS) for a Heavy-Duty Vehicle Under Steady-State Operation," SAE Technical Paper 2005-01-3798, 2005, https://doi.org/10.4271/2005-01-3798.
- Cocker, D.R. Shah, S.D. Johnson, K.C. Miller, J.W. Norbeck, J.M. “Development and Application of a Mobile Laboratory for Measuring Emissions from Diesel Engines. 1. Regulated Gaseous Emissions,” Environ. Sci. Technol. 2004 38 2182 2189
- Cocker, D.R. Shah, S.D. Johnson, K.C. Miller, J.W. Norbeck, J.M. “Development and Application of a Mobile Laboratory for Measuring Emissions from Diesel Engines. 2. Sampling for Toxics and Particulate Matter,” Environ. Sci. Technol. 2004 38 6809 6816
- Chernich, D.J. Burnitzki, M. Ianni, R. Flower, T. Riemersma, R. “Mapping Engine-out NO x Emissions Using a Chassis Dynamometer,” Proceedings of the 14 th CRC On-Road Vehicle Emissions Workshop San Diego, CA March 29-31 2004
- Khalek, I.A. Ullman, T.L. Shimpi, S.A. Jackson, C.C. Dharmawardhana, B. Silvis, W.M. Kreft, N. Harevy, R.N. Munday, D. Yamagishi, Y. Graze, R. Smitherman, J. Adkins, J. “Performance of Partial Flow Sampling Systems Relative to Full Flow CVS for Determination of Particulate Emissions under Steady-State and Transient Diesel Engine Operation,” SAE Tech. Paper 2002-01-1718
- Sierra Instruments Inc. Sierra Instruments BG-1 Micro-Dilution Test Stand Instruction Manual
- Traver, M.L. “Interlaboratory Crosscheck of Heavy-Duty Vehicle Chassis Dynamometers,” Coordinating Research Council Project E-55-1, Final Report May 2002