Claims
- 1. A method for controlling dilution air supply to a partial flow dilution tunnel of a gas sampling system, comprising:monitoring an excursion of intake air to an internal combustion engine during transient conditions; and varying the dilution air supply in response to the excursion of intake air.
- 2. The method for controlling dilution air supply of claim 1, including reacting to the excursion of intake air and varying the dilution air supply within 500 milliseconds or less.
- 3. The method for controlling dilution air supply of claim 2, including reacting to the excursion of intake air and varying the dilution air supply within 300 milliseconds or less.
- 4. The method for controlling dilution air supply of claim 1, including dividing the dilution air into a fixed dilution air stream and a variable air stream.
- 5. The method for controlling dilution air supply of claim 4, monitoring the excursion of intake air to the internal combustion engine during transient conditions includes creating an analog signal responsive to the excursion of intake air.
- 6. The method for controlling dilution air supply of claim 5, including receiving the signal; andvarying the variable air stream at an amount inversely proportional to the excursion of intake air.
- 7. The method for controlling dilution air supply of claim 1, including providing a filtered and scrubbed supply of air for the dilution air supply.
- 8. A method for sampling exhaust particles in an exhaust stream from an internal combustion engine comprising:connecting a partial flow dilution tunnel to the exhaust stream of the internal combustion engine; providing a filtered and scrubbed supply of dilution air to the partial flow dilution tunnel; varying the supply of dilution air in response to excursions of an amount of intake air supplied to the internal combustion engine; drawing the exhaust sample and the dilution air from the partial flow dilution tunnel; and filtering the exhaust sample and the dilution air to trap the exhaust particles at an outlet end of the partial flow dilution tunnel.
- 9. The method for sampling exhaust particles of claim 8, including positioning a sampling probe in the exhaust stream; andconnecting the sampling probe to the partial flow dilution tunnel.
- 10. The method for sampling exhaust particles of claim 8, including reacting to the excursion of intake air and varying the dilution air supply within 500 milliseconds or less.
- 11. The method for sampling exhaust particles of claim 10, including reacting to the excursion of intake air and varying the dilution air supply within 300 milliseconds or less.
- 12. The method for sampling exhaust particles of claim 8, including dividing the dilution air into a fixed dilution air stream and a variable air stream.
- 13. The method for sampling exhaust particles of claim 12, including monitoring the excursion of intake air to the internal combustion engine during transient conditions; andcreating an analog signal responsive to the excursion of intake air.
- 14. The method for controlling dilution air supply of claim 13, including responding to the signal; andvarying the variable air stream at an amount inversely proportional to the excursion of intake air.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of commonly-owned provisional application No. 60/304,254, filed Jul. 10, 2001.
US Referenced Citations (16)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0928962 |
Sep 1997 |
EP |
WO 0190741 |
May 2001 |
WO |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/304254 |
Jul 2001 |
US |