1994-03-01

Progress in CVS Techniques - A Variable Flow CVS 940966

Although conventional CVS (Constant Volume Sampling) equipment is well established, future requirements for measuring the emitted concentrations of regulated components from ULEV (Ultra Low Emission Vehicles) cars will require optimized dilution ratios.
By means of a needle driven by a stepper motor the variable CFV (Critical Flow Venturi)-CVS will be able to adjust the CVS maintaining critical conditions to a predefined volume in less than one second.
Using this new design and operating it with software-controlled predefined volume modes, it will be possible to optimize dilution ratios by at least a factor of three. In this case ULEV measurements could be performed by using conventional analyzers.

SAE MOBILUS

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

Access SAE MOBILUS »

Members save up to 16% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Ultra Low Sulfur Diesel (ULSD) Sulfur Test Method Variability: A Statistical Analysis of Reproducibility from the 2005 US EPA ULSD Round-Robin Test Program

2006-01-3360

View Details

TECHNICAL PAPER

Analysis of the FTP Performance of Metal Foil and Ceramic Substrate Catalytic Converters Using Statistical Methods

940742

View Details

TECHNICAL PAPER

Development of Continuous Dilution Factor for CVS Emissions Sampling and Calculation

2001-01-2815

View Details

X