Hydrogen detection with FBG sensor technology for disaster prevention

Abstract

Three fiber Bragg grating (FBG) sensors systems for hydrogen detection are presented using the classic Pd (palladium) coating technique (500 nm) as the hydrogen sensitive film and titanium (Ti) as the adhesive layer with the etched cladding. These systems are compared and used for disaster environment prevention in hydrogen leakage environment where higher values than the normal are presented which increase the risk of explosion. With these systems, 0.1%-4% of the hydrogen volume concentration range in the volume ratio was detected and monitored experimentally in the test room with the very sensitive and stable value which reached 60 pm/1% H 2. In addition, a fast response time, about 6 s, was obtained with an advanced sensor.

Hydrogen FBG sensor using Pd/Ag film with application in propulsion system fuel tank model of aerospace vehicle

“…where Λ 0 and ' 0  are the nominal grating periods, and c p (nm/cm) is the linear chirp coefficient. In the previous work of our research group that is presented in [4] as we have talked before, the effectiveness of this special design of the FBG has been shown, in which it gave the robustness, acceptable sensitivities of strain and temperature with the higher stability. With the following parameters: the length of 4 mm, Λ 0 =0.53 µm, ' 0  =0.5284 µm, c p =1.5 nm/cm, n eff =1.456, and refractive index modulation equal to 2.5×10 -4 , we obtained: 1.5424 µm as λ B , 1 pm/µε and 10 pm/℃ as the strain and temperature sensitivities, and 100% as the reflectivity.…”

“…This idea was verified also in [15]. In this paper, we want to increase the published specifications of the hydrogen FBG sensors of our research group in [4] and [16]: the sensitivity, response time, and life time, in which we used the palladium (Pd) as the hydrogen sensitive film. With these works, we had the sensitivity of 60 pm/1% H 2 and the faster response time, less than 9 s, but with a shorter lifetime, i.e.…”

“…In this paper, our results are based on a special robust FBG sensor with a length of 4 mm which is developed by our research group. The experimental results of this sensor are presented in [4]. In addition, a new alliance of the Pd-Ag (palladium-silver) material (500 nm) as the hydrogen sensitive film is used with the titanium (Ti) layer (35 nm) as the adhesive layer to enhance the strength between the Pd-Ag layer and the optic cladding.…”

Femtosecond Laser Ablated FBG with Composite Microstructure for Hydrogen Sensor Application

“…Many optical fiber hydrogen sensors based on micro-mirror optical fiber sensors [5], fiber Bragg grating (FBG) sensors [6,7,8,9], interference sensors [10], and evanescent field sensors [11] have been investigated. Due to the advantages in wavelength division multiplex, self-reference, and anti-interference, FBG sensors are more suitable for monitoring hydrogen leaks for distribution measurement [12].…”

Fiber Bragg grating sensor network optimization

“…Two aspects should be considered in the design of FBG sensor network [3]: the using efficiency of sensors and the reliability of the FBG sensor network system. These two factors are opposite to some extent.…”