Constant Volume Sampler System for Exhaust Emissions Measurement(STABILIZED Sep 2011) J1094_201109

This SAE Information Report describes uniform laboratory techniques for employing the constant volume sampler (CVS) system in measuring various constituents in the exhaust gas of gasoline engines installed on passenger cars and light trucks. The techniques described relate particularly to CVS systems employing positive displacement pumps. This is essentially an almost obsolete system relative to usage in industry and government. Current practice favors the use of a critical flow venturi to measure the diluted exhaust flow. In some areas of CVS practice, alternative procedures are given as a guide toward development of uniform laboratory techniques.

The report includes the following sections:

Introduction
1. 1. Scope
2. 2. References
3. 2.1 Applicable Publications
4. 3. Definitions
5. 4. Test Equipment
6. 4.1 Sampler
7. 4.2 Bag Analysis
8. 4.3 Modal Analysis
9. 4.4 Instrument Operating Procedures
10. 4.5 Supplementary Discussions
11. 4.6 Tailpipe Connections
12. 4.7 Chassis Dynamometer
13. 5. Operating and Calibrating Procedure
14. 5.1 Calibration
15. 5.2 Operating Procedures
16. 6. Data Analysis
17. 6.1 Bag Analysis
18. 6.2 Modal Analysis
19. 6.3 Background
20. 6.4 Fuel Economy
21. 7. Safety
22. 8. Notes