Systems and methods for non-flammable indication of incendivity

Patent metadata

Field	Value
Publication number	US-10620179-B2
Application number	US-201816181060-A
Country	US
Kind code	B2
Filing date	Nov 5, 2018
Priority date	Jul 19, 2016
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

Incendivity test systems and methods are disclosed. Incendivity test systems include a non-flammable gas mixture and a test article. The non-flammable gas mixture includes a thermally reactive reagent that is formulated to thermally react to produce a reaction product. Incendivity test systems also include an energy source configured to apply an energy discharge such as a simulated lightning strike to the test article. Incendivity test systems also include a detection device configured to measure an indicator species in the non-flammable gas mixture (e.g., the thermally reactive reagent and/or the reaction product). Incendivity test methods include contacting the test article with the non-flammable gas mixture, applying the energy discharge to the test article, and then measuring the amount of the indicator species and determining the incendivity of the test article in response to the energy discharge based upon the amount of the indicator species.

First claim

The invention claimed is:

1. An incendivity test method comprising:
contacting a test article with a non-flammable gas mixture, wherein the non-flammable gas mixture includes a thermally reactive reagent;
applying an energy discharge to the test article while the test article is in contact with the non-flammable gas mixture;
after applying the energy discharge, measuring an amount of one or more components of the non-flammable gas mixture that represents an amount of the thermally reactive reagent that reacted in response to applying the energy discharge; and
determining an incendivity of the test article in response to the energy discharge based upon the amount of the thermally reactive reagent that reacted in response to applying the energy discharge.

2. The method of claim 1 , wherein the non-flammable gas mixture is a mixture that is too lean to support self-propagating combustion of the thermally reactive reagent.

3. The method of claim 1 , wherein the applying the energy discharge includes applying a simulated lightning strike to the test article.

4. The method of claim 1 , wherein the energy discharge has a peak power of greater than 1 kW (kilowatt).

5. The method of claim 1 , wherein the measuring includes measuring an amount of a reaction product produced by thermal reaction of the thermally reactive reagent after applying the energy discharge.

6. The method of claim 1 , wherein the measuring includes measuring by a gas analysis technique selected from the group consisting of mass spectrometry, gas chromatography, and gas chromatography mass spectrometry.

7. The method of claim 1 , wherein the measuring includes measuring by an optical technique selected from the group consisting of optical spectrometry, optical absorbance, optical transmittance, optical reflectance, nephelometry, luminescence, fluorescence, phosphorescence, laser induced fluorescence, planar laser induced fluorescence, laser excited atomic fluorescence, and Fourier transform infrared spectrometry.

8. The method of claim 1 , wherein the non-flammable gas mixture includes a plurality of thermally reactive reagents, wherein each of the thermally reactive reagents is configured to react in response to a different ignition source to produce a corresponding reaction product.

9. The method of claim 1 , wherein the thermally reactive reagent is a combustion fuel.

10. The method of claim 1 , wherein the thermally reactive reagent is configured to thermally decompose.

11. The method of claim 1 , wherein the thermally reactive reagent is a halocarbon.

12. The method of claim 1 , wherein the contacting includes immersing the test article in the non-flammable gas mixture.

13. The method of claim 1 , wherein the contacting includes flowing a stream of the non-flammable gas mixture over the test article.

14. The method of claim 13 , wherein the flowing includes recirculating the non-flammable gas mixture over the test article.

15. The method of claim 1 , further comprising preparing the non-flammable gas mixture by mixing the thermally reactive reagent with one or more of an oxidant, a diluent, and another thermally reactive reagent.

16. The method of claim 1 , wherein the contacting includes contacting the test article with the non-flammable gas mixture at a pressure of at least 50 kPa.

17. The method of claim 1 , wherein the thermally reactive reagent includes at least one of a thermally reactive gas and a thermally reactive aerosol.

18. The method of claim 1 , wherein the non-flammable gas mixture includes an aerosol of the thermally reactive reagent.

19. The method of claim 1 , wherein the non-flammable gas mixture includes an oxidant, and wherein the non-flammable gas mixture includes a plurality of thermally reactive reagents and each of the thermally reactive reagents is configured to react with the oxidant in response to a different ignition source to produce a corresponding reaction product.

20. The method of claim 1 , wherein the non-flammable gas mixture includes a plurality of thermally reactive reagents, and wherein the non-flammable gas mixture includes a plurality of corresponding oxidants wherein each corresponding oxidant is configured to react with at least one of the thermally reactive reagents to produce a corresponding reaction product.

21. The method of claim 1 , wherein the determining the incendivity includes comparing a parameter related to the amount of thermally reactive reagent that reacted to a predefined threshold.

22. The method of claim 1 , wherein the determining the incendivity includes determining that the test article generated an ignition hazard in response to the energy discharge based upon whether the amount of thermally reactive reagent that reacted is greater than a predefined threshold.

23. The method of claim 1 , wherein the determining the incendivity includes determining a level of incendivity based upon the amount of thermally reactive reagent that reacted.

24. The method of claim 1 , further comprising, before or after the applying the energy discharge and the measuring the amount of one or more component, verifying the non-flammable gas mixture reacts to a thermal input by discharging a controlled ignition source in the non-flammable gas mixture and, after the controlled ignition source discharge, measuring the amount of one or more components of the non-flammable gas mixture to verify that at least a portion of the thermally reactive reagent reacted in response to discharging the controlled ignition source.

25. The method of claim 24 , wherein the verifying is performed after the determining the incendivity of the test article.

26. The method of claim 1 , wherein the test article is at least one of an aircraft skin, an aircraft frame, an aircraft wing, a fuel handling component, a fuel system, a fuel tank, a fuel pump, and an electrical enclosure.

27. An incendivity test system comprising:
a non-flammable gas mixture, wherein the non-flammable gas mixture includes a thermally reactive reagent that is formulated to thermally react to produce a reaction product;
a test article in contact with the non-flammable gas mixture;
an energy source configured to apply an energy discharge to the test article; and
a detection device configured to measure an amount of one or more indicator species selected from the group consisting of a component of the non-flammable gas mixture and the reaction product.

Assignees

• Boeing Co

Inventors

• Damazo Jason Scott
• Kwon Eddie
• Robb Andrew Michael

Classifications

• G01N31/12

  using combustion (G01N25/20 takes precedence) · CPC title

• G01N33/22 Primary

  Fuels; Explosives · CPC title

• Y10T436/24

  Nuclear magnetic resonance, electron spin resonance or other spin effects or mass spectrometry · CPC title

• Y10T436/196666

  Carbon containing compound [e.g., vinylchloride, etc.] · CPC title

• G01N25/52 Primary

  by determining flash-point of liquids · CPC title