Real-time exhaust gas modular flowmeter and emissions reporting system for mobile apparatus

• US 6,470,732 B1
• Filed: 11/20/2000
• Issued: 10/29/2002
• Est. Priority Date: 01/05/1998
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Breton, Leo Alphonse Gerard
• Primary Examiner(s): MCCALL, ERIC SCOTT
• Application Number:
  US09/715,067
• Time in Patent Office: 708 Days
• Field of Search: 73/233.1, 73/233.2, 731/16, 731/172, 731/173, 731/181
• US Class Current: 73/23.31
• CPC Class Codes: F01N 13/008 Mounting or arrangement of exhaust sensors in or on exhaust apparatus sensor arrangements for engine control F02D41/1439
• CPC Class Codes: G01F 1/46 Pitot tubes
• CPC Class Codes: G01F 9/001 with electric, electro-mechanic or electronic means G01F9/008 and G01F9/02 take precedence
• CPC Class Codes: G01M 15/102 by monitoring exhaust gases
• CPC Class Codes: G01M 15/106 using pressure sensors

Abstract

A real-time emissions reporting system includes an instrument module adapted to be detachably connected to the exhaust pipe of a combustion engine to provide for flow of exhaust gas therethrough. The instrument module includes a differential pressure probe which allows for determination of flow rate of the exhaust gas and a gas sampling tube for continuously feeding a sample of the exhaust gas to a gas analyzer or a mounting location for a non-sampling gas analyzer. In addition to the module, the emissions reporting system also includes an elastomeric boot for detachably connecting the module to the exhaust pipe of the combustion engine, a gas analyzer for receiving and analyzing gases sampled within the module and a computer for calculating pollutant mass flow rates based on concentrations detected by the gas analyzer and the detected flowrate of the exhaust gas. The system may also include a particulate matter detector with a second gas sampling tube feeding same mounted within the instrument module.

Claims

1. A real-time, emissions reporting system, for an internal combustion engine mounted on a mobile apparatus, comprising:

flow determination means, mounted for travel with said mobile apparatus and operative during movement of said mobile apparatus, for determining flow rate of exhaust gas of said mobile apparatus, during the movement;

a gas analyzer for detecting concentration of each of plurality of gaseous pollutants within the exhaust gas; and

calculating means for calculating and reporting mass flow rates for the gaseous pollutants in real-time based on the determined flow rate of the exhaust gas and on the detected concentrations.

2. An emissions reporting system according to claim 1 wherein mass flow rates are each calculated as a unit mass or gaseous pollutant per unit distance traveled and further comprising distance detecting means for continuously detecting distance traveled by the mobile apparatus.

3. An emissions reporting system according to claim 2 wherein said distance detecting means is a scan tool which receives data from an engine computer on-board the mobile apparatus and which transmits the received data to said calculating means.

4. An emissions reporting system according to claim 3 wherein said calculating means, based on the data received from the scan tool, correlates the calculated mass flow rates with at least one engine operating parameter.

5. An emissions reporting system according to claim 1 wherein said means for determining the flow rate of the exhaust gas is a flowmeter which directly measures an actual exhaust gas flow rate.

6. An emissions reporting system according to claim 5 wherein mass flow rates are each calculated as a unit mass or gaseous pollutant per unit distance traveled and further comprising distance detecting means for continuously detecting distance traveled by the mobile apparatus.

7. An emissions reporting system according to claim 6 wherein said distance detecting means is a scan tool which receives data from an engine computer on-board the mobile apparatus and which transmits the received data to said calculating means.

8. An emissions reporting system according to claim 7 wherein said calculating means, based on the data received from the scan tool, correlates the calculated mass flow rates with at least one engine operating parameter.

9. An emissions reporting system according to claim 6 wherein said distance detecting means is a global positioning system receiver for continuously receiving signals for calculating present speed and position of the mobile apparatus.

23. An emissions reporting system according to claim 5 additionally comprising:

a particulates detector for determining concentration of particulates in the exhaust gas.

24. An emissions reporting system according to claim 23 wherein said gas analyzer and said particulates detector have detecting elements mounted at the same location relative to the exhaust gas flow.

10. A real-time emissions reporting system, for an internal combustion engine mounted on a mobile apparatus for travel therewith, said system comprising:

a module for detachably mounting on the mobile apparatus and containing a flow sensing element;

support means for attaching said module to a body portion of the mobile apparatus;

connecting means for detachably connecting said module to an exhaust pipe of the internal combustion engine, whereby flow rate of exhaust gas of the internal combustion engine is detected by said flow sensing element;

a gas analyzer for detecting concentration of each of a plurality of gaseous pollutants within the exhaust gas; and

calculating means for calculating mass flow rates for each of said gaseous pollutants based on the detected concentrations and the detected flow rate of the exhaust gas.

11. An emissions reporting system according to claim 10 wherein gas concentration detection element, which sends signals to said gas analyzer, is mounted within said module.

12. An emissions reporting system according to claim 10 wherein the internal combustion engine is equipped with a catalytic converter and said gas analyzer is a downstream gas analyzer for detecting concentrations of each of said plurality of gaseous pollutants in the exhaust gas downstream of the catalytic converter, said emissions reporting system further comprising:

an upstream gas analyzer for detecting concentrations of each of said plurality of gaseous pollutants in the exhaust gas upstream of the catalytic converter, said calculating means determining an efficiency for the catalytic converter by comparing the concentrations detected by said upstream gas analyzer with the concentrations detected by said downstream gas analyzer.

13. An emissions reporting system according to claim 10 additionally comprising:

an open-ended gas sampling tube, mounted within said module for continuously sampling the exhaust gas inclusive of particulates; and

at least one removably mounted filter element whereby said one filter element may be weighed before and after a known period of time during which exhaust gas from said open-ended sampling tube is passed through said one filter element to determine concentration of particulates.

14. An emissions reporting system according to claim 10 wherein mass flow rates are each calculated as a unit mass of gaseous pollutant per unit distance traveled and further comprising distance detecting means for continuously detecting distance traveled by the mobile apparatus.

15. An emissions reporting system according to claim 14 wherein said distance detecting means is a scan tool which receives data from an engine computer on-board the mobile apparatus and which transmits the received data to said calculating means.

16. An emissions reporting system according to claim 15 wherein said calculating means, based on the data received from the scan tool, correlates the calculated mass flow rates with at least one engine operation parameter.

17. An emissions reporting system according to claim 10 additionally comprising:

a global positioning system receiver for continuously receiving signals for use in calculating present position of the mobile apparatus; and

wherein said calculating means repeatedly computes present position of the mobile apparatus based on the signals from said receiver and correlates the computed present positions with the calculated mass flow rates of said pollutants.

18. An emissions reporting system according to claim 10 wherein said calculating means also calculates fuel economy in real time.

19. An emissions reporting system according to claim 10 further comprising support means for attaching and fixing said module to a body portion of the mobile apparatus.

20. An emissions reporting system according to claim 10, wherein said module comprises:

a module housing including a straight pipe section having an open interior;

a flow sensing element mounted within said straight pipe section for determining the velocity of the exhaust gas flow through the open interior of said straight pipe section; and

a gas sampling mount extending into said open interior at a position fixed relative to said flow sensing element for obtaining a sample of the exhaust gas and for communicating with the gas analyzer.

21. An emissions reporting system according to claim 20 wherein said module further comprises:

a pressure detector for detecting pressure of the exhaust gas flow adjacent said flow sensing element; and

a temperature probe for detecting temperature of the exhaust gas flow adjacent said flow sensing element.

22. An emissions reporting system according to claim 21 wherein said pressure detector comprises an annular jacket sealed around the exterior of said straight pipe section and a plurality of spaced holes extending through said straight pipe section and around the circumference of said straight pipe section, said plurality of holes providing fluid communication between said open interior and said annular jacket and a pressure detector, in fluid communication with said annular jacket.

25. An emissions reporting system according to claim 10 additionally comprising:

a particulates detector for determining concentration of particulates in the exhaust gas.

26. An emissions reporting system according to claim 25 wherein said gas analyzer and said particulates detector have detecting elements mounted at the same location relative to the exhaust gas flow.