A Sampling System for the Measurement of PreCatalyst Emissions from Vehicles Operating Under Transient Conditions General Motors Corporation

Format:

Conference/Event

Author/Creator:

McLeod, Jon, author.

Conference Name:

International Congress & Exposition (1993-03-01 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 1993

Summary:

A proportional sampler for vehicle feedgas and tailpipe emissions has been developed that extracts a small, constant fraction of the total exhaust flow during rapid transient changes in engine speed. Heated sampling lines are used to extract samples either before or after the catalytic converter. Instantaneous exhaust mass flow is measured by subtracting the CVS dilution air volume from the total CVS volume. This parameter is used to maintain a constant dilution ratio and proportional sample. The exhaust sample is diluted with high-purity air or nitrogen and is delivered into Tedlar sample bags. These transient test cycle weighted feedgas samples can be collected for subsequent analysis of hydrocarbons and oxygenated hydrocarbon species. This "mini-diluter" offers significant advantages over the conventional CVS system. The concentration of the samples are higher than those collected from the current CVS system because the dilution ratio can be optimized depending on the fuel. Contaminants in dilution air are eliminated since dilution is carried out using high-purity gases. This report describes the design, construction, and experimental studies to validate the performance of the mini-diluter for the collection and measurement of total carbon and individual hydrocarbon species in vehicle exhaust ahead of the catalytic converter

Notes:

Vendor supplied data

Publisher Number:

930141

Access Restriction:

Restricted for use by site license