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Novel fiber optic sensor probe with a pair of highly reflected connectors and a vessel of water absorption material for water leak detection.

Cho TS, Choi KS, Seo DC, Kwon IB, Lee JR - Sensors (Basel) (2012)

Bottom Line: A novel fiber optic sensor probe is devised with a vessel of water absorption material called as water combination soil (WCS) located between two highly reflected connectors: one is a reference connector and the other is a sensing connector.In this study, the sensing output is calculated from the reflected light signals of the two connectors.The sensor probe with a high output value provides a high sensitivity with various detection levels while the number of total installable sensor probes decreases.

View Article: PubMed Central - PubMed

Affiliation: Center for Safety Measurement, Korea Research Institute of Standards and Science, 1 Doryong-dong Yuseong-gu, Daejeon 305-340, Korea. tscho@kriss.re.kr

ABSTRACT
The use of a fiber optic quasi-distributed sensing technique for detecting the location and severity of water leakage is suggested. A novel fiber optic sensor probe is devised with a vessel of water absorption material called as water combination soil (WCS) located between two highly reflected connectors: one is a reference connector and the other is a sensing connector. In this study, the sensing output is calculated from the reflected light signals of the two connectors. The first reflected light signal is a reference and the second is a sensing signal which is attenuated by the optical fiber bending loss due to the WCS expansion absorbing water. Also, the bending loss of each sensor probe is determined by referring to the total number of sensor probes and the total power budget of an entire system. We have investigated several probe characteristics to show the design feasibility of the novel fiber sensor probe. The effects of vessel sizes of the probes on the water detection sensitivity are studied. The largest vessel probe provides the highest sensitivity of 0.267 dB/mL, while the smallest shows relatively low sensitivity of 0.067 dB/mL, and unstable response. The sensor probe with a high output value provides a high sensitivity with various detection levels while the number of total installable sensor probes decreases.

No MeSH data available.


Related in: MedlinePlus

Bending loss according to bending diameters and arc angles of an optical fiber (SMF-28).
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f10-sensors-12-10906: Bending loss according to bending diameters and arc angles of an optical fiber (SMF-28).

Mentions: As shown in Figure 9, the bending losses at the location of two probes are almost same and the differences are less than 1 dB in the bending diameter range of 12–24 mm. However the bending losses are gradually increased according to the decrease of the bending diameter. In Figure 9, the curves show the bending loss effect due to the bending diameter. The bending loss is generally directly related to the radius of curvature and the arc length [17]. The output power of the sensor probe considering bending loss, Pout, will be as follows:(5)Pout=C1Pinexp(−C2γs)where C1 and C2 are constants that depend on the dimensions of the waveguide, and on the shape of the optical mode. Pin is an input power, γ is the radius of curvature, s is an arc length. By employing an arc angle, we can evaluate the radius of curvature. In order to investigate the radius and arc angle of our sensor probe, we measure the vertical location of the optical fiber and use trigonometric relations to determine the bending radius, as shown in Figure 10.


Novel fiber optic sensor probe with a pair of highly reflected connectors and a vessel of water absorption material for water leak detection.

Cho TS, Choi KS, Seo DC, Kwon IB, Lee JR - Sensors (Basel) (2012)

Bending loss according to bending diameters and arc angles of an optical fiber (SMF-28).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472865&req=5

f10-sensors-12-10906: Bending loss according to bending diameters and arc angles of an optical fiber (SMF-28).
Mentions: As shown in Figure 9, the bending losses at the location of two probes are almost same and the differences are less than 1 dB in the bending diameter range of 12–24 mm. However the bending losses are gradually increased according to the decrease of the bending diameter. In Figure 9, the curves show the bending loss effect due to the bending diameter. The bending loss is generally directly related to the radius of curvature and the arc length [17]. The output power of the sensor probe considering bending loss, Pout, will be as follows:(5)Pout=C1Pinexp(−C2γs)where C1 and C2 are constants that depend on the dimensions of the waveguide, and on the shape of the optical mode. Pin is an input power, γ is the radius of curvature, s is an arc length. By employing an arc angle, we can evaluate the radius of curvature. In order to investigate the radius and arc angle of our sensor probe, we measure the vertical location of the optical fiber and use trigonometric relations to determine the bending radius, as shown in Figure 10.

Bottom Line: A novel fiber optic sensor probe is devised with a vessel of water absorption material called as water combination soil (WCS) located between two highly reflected connectors: one is a reference connector and the other is a sensing connector.In this study, the sensing output is calculated from the reflected light signals of the two connectors.The sensor probe with a high output value provides a high sensitivity with various detection levels while the number of total installable sensor probes decreases.

View Article: PubMed Central - PubMed

Affiliation: Center for Safety Measurement, Korea Research Institute of Standards and Science, 1 Doryong-dong Yuseong-gu, Daejeon 305-340, Korea. tscho@kriss.re.kr

ABSTRACT
The use of a fiber optic quasi-distributed sensing technique for detecting the location and severity of water leakage is suggested. A novel fiber optic sensor probe is devised with a vessel of water absorption material called as water combination soil (WCS) located between two highly reflected connectors: one is a reference connector and the other is a sensing connector. In this study, the sensing output is calculated from the reflected light signals of the two connectors. The first reflected light signal is a reference and the second is a sensing signal which is attenuated by the optical fiber bending loss due to the WCS expansion absorbing water. Also, the bending loss of each sensor probe is determined by referring to the total number of sensor probes and the total power budget of an entire system. We have investigated several probe characteristics to show the design feasibility of the novel fiber sensor probe. The effects of vessel sizes of the probes on the water detection sensitivity are studied. The largest vessel probe provides the highest sensitivity of 0.267 dB/mL, while the smallest shows relatively low sensitivity of 0.067 dB/mL, and unstable response. The sensor probe with a high output value provides a high sensitivity with various detection levels while the number of total installable sensor probes decreases.

No MeSH data available.


Related in: MedlinePlus