(24a) Fiberoptic Hydrogen Leak Detector

Fiber optic sensors for hydrogen leak detection have unique advantages with the potential to address many of the shortcomings of other technologies. Fiber optic sensors have a small form factor and are lightweight. Due to the nature of their operation, they can be deployed in hazardous environments and monitored from a remote location. They are safe in explosive environments and are immune to electromagnetic interference. They can be optimized for any desired parameter-of-interest and in some cases measure multiple parameters simultaneously. Fiber optic hydrogen sensors can be orders of magnitude more sensitive than their counterparts using electrical technologies.

Like many electrical sensors, our approach incorporates palladium as the critical sensing component. Uniquely, we accurately measure the expansion of palladium when exposed to hydrogen and temperature with fiber optic sensors. Since temperature is a major factor in determining the concentration of the hydrogen leak, the ability to measure temperature and hydrogen concentration simultaneously is necessary. In this paper we report on results of our sensor development and testing. This includes tests at 2% hydrogen in nitrogen which result in a measured sensor response time of less than 10 seconds.