Claims
- 1. A method for analyzing and evaluation fluids which are subject to degradation and/or contamination comprising the steps of:
- bringing a single electrode into contact with a sample of a fluid to be analyzed such that the electrode is electrically connected to the ground potential by the fluid;
- applying a square voltage wave form to the electrode at a predetermined scan range and scan rate to cause a current to flow between the electrode and ground potential;
- maintaining the scan range between about +20V and about -20V to ensure that the monitored current is based entirely on the conductivity of the fluid;
- intermittently or continuously monitoring the current at the single electrode to determine a current output signal; and
- using the current output signal to measure the conductivity of the fluid and determine the remaining useful life thereof.
- 2. The method of claim 1 wherein the scan range is about +10V to about -10V.
- 3. The method of claim 2 wherein the scan rate is a value selected from about 1 to about 100 Hertz.
- 4. The method of claim 3 wherein the step of bringing the electrode into contact with the sample includes the step of attaching the electrode on-line.
- 5. The method of claim 4 further including the step of comparing the measured conductivity of the fluid with a known conductivity value for the fluid to determine the remaining useful life for the fluid and/or whether the fluid is contaminated.
- 6. The method of claim 5 wherein the fluid is selected from the group consisting of fuel oils, lubricating oils, lubricating fluids, transmission fluids, coolants, hydraulic fluids and cooking oils.
- 7. The method of claim 3 wherein the step of monitoring the current is done continuously.
- 8. The method of claim 3 wherein the step of monitoring the current is done intermittently.
- 9. The method of claim 1 wherein the step of bringing the electrode into contact with the sample includes the step of placing the electrode in an on-line sample reservoir and the method also includes the additional step of removing the electrode from the sample reservoir when the analysis is concluded.
- 10. The method of claim 1 wherein the electrode is a single stainless steel rod.
- 11. A method for analyzing and evaluating fluids which are subject to degradation and/or contamination comprising the steps of:
- attaching a single electrode on-line and in contact with a sample of a fluid to be analyzed such that the single electrode is electrically connected to the ground potential by the fluid;
- applying a square voltage wave form to the single electrode at a scan range of about .+-.10V to ensure that the monitored current is based entirely on the conductivity of the fluid and at a scan rate which is a single value selected from about 1 to about 100 Hertz, the square voltage wave form being applied to cause a current to flow between the single electrode and the ground potential;
- intermittently or continuously monitoring the current at the single electrode to determine a current output signal; and
- using the current output signal to measure the conductivity of the fluid and determine the remaining useful life thereof.
- 12. The method of claim 11 further including the step of comparing the measured conductivity of the fluid with a known conductivity value for the fluid to determine the remaining useful life of the fluid and/or whether the fluid is contaminated.
- 13. The method of claim 12 wherein the fluid is selected from the group consisting of fuel oils, lubricating oils, lubricating fluids, transmission fluids, coolants, hydraulic fluids and cooking oils.
- 14. The method of claim 11 wherein the electrode is a single stainless steel rod.
Government Interests
The United States Government has rights in this invention pursuant to Contract No. F33615-92-C-2207 awarded by the Department of the Air Force.
US Referenced Citations (18)
Foreign Referenced Citations (3)
Number |
Date |
Country |
20 27 947 |
Jun 1970 |
DEX |
WO 8801740 |
Mar 1988 |
WOX |
WO 9608711 |
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WOX |
Non-Patent Literature Citations (2)
Entry |
Le point sur les capteurs by Daniel Mansion, entitle "Mesure de conductivite de liquides" (XP 002047209). (no date). |
International Search Report, dated Jan. 5, 1998. |