CVS SYSTEM SAMPLE WATER VAPOR MANAGEMENT

• US 20120210803A1
• Filed: 05/03/2012
• Published: 08/23/2012
• Est. Priority Date: 09/15/2006
• Status: Active Grant

• Current Assignee: AVL Test Systems, Inc.
• Original Assignee: AVL Test Systems, Inc.
• Inventors: Silvis, William Martin, Williamson, James
• Granted Patent: US 9,097,623 B2
• Time in Patent Office: Days
• US Class Current: 73/863.02
• CPC Class Codes: G01M 15/102 by monitoring exhaust gases
• CPC Class Codes: G01N 1/2252 in a vehicle exhaust
• CPC Class Codes: G01N 2001/2255 with dilution of the sample
• CPC Class Codes: G01N 2001/2264 with dilution

Abstract

An exhaust sampling system includes a pre-fill gas source having a pre-fill gas. A sampling conduit is configured to collect exhaust gas and make-up gas. A sample bag is fluidly connected to the sampling conduit and the pre-fill gas source. A controller is programmed to run a test procedure in which a sample of exhaust gas and make-up gas is collected in the sample bag. The controller sends a command that fills the sample bag with pre-fill gas prior to the test procedure. The pre-fill gas remains in the sample bag during the test procedure. In one example, the amount of pre-fill gas is selected to prevent the sample from condensing in the sample bag during the test procedure. In another example, the amount of pre-fill gas is selected to provide a sufficient volume of gases for analysis during the test procedure.

Claims

1. An engine emissions test system comprising:

a tunnel configured to receive exhaust from an engine;

a sampler configured to extract a sample of exhaust from the tunnel;

at least one sample bag configured to store the sample of exhaust;

a bag fill circuit configured to communicate the sample of exhaust between the sampler and the at least one sample bag, the bag fill circuit including a pump and a flow meter; and

a fill gas line configured to communicate a fill gas from a fill gas source to the bag fill circuit dep;

(at a point between the flow meter of the bag fill circuit and the at least one sample bag).

2. The system as recited in claim 1, wherein the flow meter of the bag fill circuit is downstream of the pump of the bag fill circuit.

3. The system as recited in claim 2, wherein the bag fill circuit further includes at least one valve between the flow meter of the bag fill circuit and the at least one sample bag.

4. The system as recited in claim 3, wherein the bag fill circuit further includes a valve between the sampler and the pump of the bag fill circuit.

5. The system as recited in claim 1, wherein the fill gas line includes a pump and a flow meter.

6. The system as recited in claim 5, wherein the flow meter of the fill gas line is downstream of the pump of the fill gas line.

7. The system as recited in claim 6, wherein the fill gas line includes a valve between the pump of the fill gas line and the flow meter of the fill gas line.

8. The system as recited in claim 1, wherein the exhaust sampled from the tunnel is diluted with a make-up gas.

9. The system as recited in claim 1, wherein the fill gas is ambient air.

10. The system as recited in claim 1, further including a controller programmed to send a command that provides the at least one sample bag with the fill gas.

11. The system as recited in claim 10, wherein the controller is programmed to fill the at least one sample bag with the fill gas prior to a test procedure.

12. An engine emissions test system comprising:

a tunnel configured to receive exhaust from an engine;

at least one sample bag configured to store a sample of exhaust;

an read circuit configured to communicate the stored exhaust sample between the at least one sample bag and an analyzer; and

a fill gas line configured to communicate a fill gas to be mixed with the exhaust sample, the fill gas line extending between a fill gas source and the read circuit.

13. The system as recited in claim 12, wherein the read circuit includes first and second read line sections, wherein the first read line section doubles as a portion of a bag fill circuit configured to communicate the sample of exhaust between the sampler and the at least one sample bag, the bag fill circuit including a pump and a flow meter.

14. The system as recited in claim 13, wherein the second read line section includes a pump and a flow meter, the pump and flow meter each provided between the first read line section and the analyzer.

15. The system as recited in claim 14, wherein the second read line section includes a valve between the pump of the second read line section and the flow meter of the second read line section.

16. The system as recited in claim 12, wherein the fill gas is a diluent.