IDENTIFICATION, QUANTIFICATION AND REDUCTION OF SOURCES OF VARIABILITY IN VEHICLE EMISSIONS AND FUEL ECONOMY MEASUREMENTS

A major problem in vehicle exhaust emissions and fuel economy testing has been the variability in the measurements. An extensive test program was undertaken to identify and quantify the sources of variation. The test program was designed using four test vehicles on five CTE-50 Clayton dynamometer cells whereby four repeats for each combination were provided for a total of 80 CVS-C/H emissions and fuel economy tests. The paper reports various results of this experiment and describes an instrumentation package that was developed for "on-line" data recording. A brief discussion of the software used for "off-line" processing of the voluminous data as well as several statistical analysis techniques which were developed especially for identifying and quantifying the sources of variation, are included. The benefits which result from reduced test variability, namely lower test cost because of improved test efficiency and increased confidence in results, are pointed out.

• Supplemental Notes:
  • From the Meeting held February 26-March 2, 1979.
• Corporate Authors:

  Society of Automotive Engineers (SAE)

  400 Commonwealth Drive
  Warrendale, PA  United States  15096
• Authors:
  • Sheth, N J
  • Rice, T I
• Publication Date: 1979

Media Info

• Features: References;
• Pagination: 40 p.
• Serial:
  • Society of Automotive Engineers Preprint
  • Publisher: Society of Automotive Engineers (SAE)

Subject/Index Terms

• TRT Terms: Air quality management; Benefit cost analysis; Dynamometers; Emissions testing; Exhaust gases; Fuel conservation; Fuel consumption; Internal combustion engines; Measurement; Motor vehicles; Pollutants; Software; Statistical analysis; Vehicle power plants
• Old TRIS Terms: Automobile engines; Vehicle fuel economy testing
• Subject Areas: Data and Information Technology; Energy; Highways; Vehicles and Equipment;

Filing Info

• Accession Number: 00310340
• Record Type: Publication
• Source Agency: Engineering Index
• Report/Paper Numbers: SAE 790232
• Files: TRIS
• Created Date: Jun 9 1980 12:00AM