Experimental Methods for Reducing Uncertainty of Measurement on Vehicle Emission Testing

Tadeu C. Cordeiro de Melo; André Luiz Fonseca Dias

doi:10.4271/2004-01-1961

2004-06-08

Experimental Methods for Reducing Uncertainty of Measurement on Vehicle Emission Testing 2004-01-1961

Uncertainty in measurements is a complex issue in the process of obtaining accurate results in a vehicle emission test. Based on the ISO GUM (Guide to the expression of uncertainty in measurement), a study was carried out to calculate the final uncertainty of measurement during a vehicle emission test following a feasible method that can be used in many laboratories. When applying the methods in other laboratories high uncertainty values may be obtained for some pollutants making the compliance with emission requirements a difficult task to attain.

To reduce expanded uncertainty of measurement, it is necessary to estimate and reduce the influence of several variables on the final result, including type B (calibration certificates, reference materials, transducers and sensors, calculations) and type A (repeatability) uncertainty budgets.

This paper describes the steps followed in some experimental methods for reducing the uncertainty in measurements in light duty vehicle emission tests, including gas pollutants (CO, NO_X, HC and CO₂) and aldehydes, both in g/km (grams/kilometer). This paper also provides an overview of Brazilian emission legislation and some procedures for vehicle emission testing.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Digital $37.00 Print $37.00

Preview Document

We also recommend:

Standards

SAE Mobilus®

Publications

News

Events

Professional Development

A World in Motion (PreK-12)

Participate with SAE

SAE Membership

Donate

Experimental Methods for Reducing Uncertainty of Measurement on Vehicle Emission Testing 2004-01-1961

SAE MOBILUS