Full Content is available to subscribers

Subscribe/Learn More  >

Measuring and Comparing Accuracy of Emissions Analyzers for Use With IC Engines

[+] Author Affiliations
Dan Cordon, Steve Beyerlein, Karen DenBraven

University of Idaho, Moscow, ID

Judi Steciak

University of Idaho, Boise, ID

Paper No. IMECE2009-11295, pp. 249-254; 6 pages
  • ASME 2009 International Mechanical Engineering Congress and Exposition
  • Volume 3: Combustion Science and Engineering
  • Lake Buena Vista, Florida, USA, November 13–19, 2009
  • Conference Sponsors: ASME
  • ISBN: 978-0-7918-4376-5 | eISBN: 978-0-7918-3863-1
  • Copyright © 2009 by ASME


Automotive emission analyzers vary in price from under $1000 to well over $100,000. Different analyzers use various technologies to detect exhaust concentrations, and differ in how they condition the sample — leading to a difference in price and performance. Manufacturer claims on accuracy from less expensive analyzers are often similar to much more expensive analyzers. With a variety of analyzers available in the Small Engine Research Facility (SmERF) at the University of Idaho, this often leads to confusion in reporting accuracy of exhaust gas measurements. This study benchmarks the performance of three different analyzers: A portable 5-gas analyzer using NDIR and electrochemical cells which costs ∼$5000, a portable 7-gas analyzer using separate sensors for each gas which costs ∼$10,000, and a FTIR spectrometer which costs ∼$100,000. High and low concentrations of single-species calibration gases (methane, carbon monoxide, carbon dioxide, nitrous oxide, hydrogen, and oxygen) were run through each machine. Initial findings showed that all species measured by the 5-gas analyzer were precise around the point of calibration, with CO and CO2 quite accurate across their whole range. The 7-gas analyzer was less accurate than the 5-gas when measuring CO, CO2, and O2, but was far more accurate for THC, NO, and NO2 measurements. The FTIR was very precise provided that water vapor was effectively removed and sample lines were adequately heated. Both of the less expensive analyzers showed reduced accuracy the further away from their calibration points. Because of high setup time, use of the FTIR should be limited to detailed emissions studies, and is not recommended for coarse tuning of an engine.

Copyright © 2009 by ASME



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In