Papers by Author: Li Hua Cai

Abstract: The optical fiber corrosion sensor was applied to measure the steel corrosion based on Fe-C corrosion-sensitive metal film, the sensing principle of which was introduced. Because corrosion was a complex random phenomenon and the corrosion surface of Fe-C alloy film of the optical fiber corrosion sensor possessed fractal characteristics, the image fractal dimensions was as a quantitative index of the sensor corrosion degree. The experimental results showed that the complexity level of the sensor surface morphology increased and the optical output power increased along with the increase of fractal dimensions. Therefore, a new method was provided for the research of the optical fiber corrosion sensor.

Abstract: In this work a novel monitoring method was developed to measure the underground stray current in coal mine with fiber current sensing technique. According to the theory of optical fiber current sensor based on Faraday magneto-optic effect, a fiber sensing system was designed and the relative experiments with current generator simulating stray current were completed. The results indicate that the measurement was influenced by birefringence and temperature change. The sensing heads with high cylindrical birefringence optical fiber had a good suppressing effect on linear birefringence and the polarization state of polarized light was also more stable than that with low birefringence optical fiber. The fiber current sensing method is doable in underground stray current monitoring system in coal mine.