Fibre optic humidity sensor designed for highly alkaline environments

Bremer, Kort; Meinhardt‐Wollweber, Merve; Guenther, Stefan; Werner, G.; Sun, Tao; Grattan, K. T. V.; Roth, Bernhard

doi:10.1117/12.2059637

Cited by 3 publications

(5 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the study reported here underpins a body of research carried out by CUL in the development and application of photonic sensors (Alwis et al, 2017); Alwis et al, 2013a); Alwis et al, 2013a;Alwis et al, 2013b;Bremer et al, 2014a, Bremer et al, 2014bSun et al, 2012)…”

Section: Sensors Fabricationmentioning

confidence: 85%

Innovation in Corrosion Monitoring in Sewers

Bustamante¹,

Alwis²,

Grattan³

et al. 2017

Water e-Journal

View full text Add to dashboard Cite

Humidity plays a key role in microbiologically induced corrosion of concrete gravity sewers. Minor reductions in humidity can reduce corrosion rates. No reliable long lived (>1 week) humidity sensors are available, thus limiting the development of useful models to better manage corrosion. This paper describes the successful evaluation of purpose built photonic sensors for five months in the sewer. Survival of the photonic sensors in this environment demonstrated their suitability for longer-term sewer monitoring. The use of photonic sensors provided on-line, long term, continuous humidity data in a way that was not possible in gravity sewers prior to this study.

show abstract

Section: Sensors Fabricationmentioning

confidence: 85%

Innovation in Corrosion Monitoring in Sewers

Bustamante¹,

Alwis²,

Grattan³

et al. 2017

Water e-Journal

View full text Add to dashboard Cite

show abstract

“…A detailed description of the operation and packaging of the FBG based humidity sensor can be found elsewhere [16]. The FBG based humidity sensor employed consists of a bare and a polyimide (PI)-coated FBG, with both FBGs multiplexed in series along the fibre.…”

Section: Fbg Based Humidity Sensormentioning

confidence: 99%

“…Although not measured directly, based on prior work and a knowledge of how the characteristics of these devices change with coating thickness, the humidity sensitivity and response time, the thickness of the PI coating was estimated to be approximately 35 m [18]. As the packaging of the FBG based humidity sensor has no direct influence on the sensor response [16], the response time and sensitivity can be optimized by changing the coating thickness [18]. However, in terms of detecting leakages in sewerage tunnels the response time and sensitivity of the current device were designed to be well suited to this specific application.…”

Section: Evaluation Of Fbg Based Humidity Sensormentioning

confidence: 99%

“…Resistance of the FBG based humidity sensor to the presence of the alkaline pore water. RH measurements were performed using the climate chamber (Memmert CTC256) for increasing and decreasing humidity levels and the measurement of the Bragg wavelength of the PI-coated FBG before and after immersion in the prepared alkaline solution [16].…”

Section: Resistance To Alkaline Pore Watermentioning

confidence: 99%

See 1 more Smart Citation

Sewerage tunnel leakage detection using a fibre optic moisture-detecting sensor system

Bremer

Meinhardt‐Wollweber

Thiel³

et al. 2014

Sensors and Actuators A: Physical

Self Cite

View full text Add to dashboard Cite

This is the accepted version of the paper.This version of the publication may differ from the final published version. Permanent repository link a b s t r a c tThe design and development of a new fibre optic sensor system for the optical detection of leakages in sewerage tunnels is reported. The system developed overcomes the disadvantages of the usually employed camera based inspection systems which are relatively complex and, in addition, require cleaning of the structures to be monitored beforehand. The sensor concept created combines a Fibre Bragg Grating (FBG)-based humidity sensor and a swellable polymeric fibre optic sensor. Both sensors are located along the sewerage tunnel so that they can response immediately to any leakages that may occur. The swellable polymeric fibre optic sensor shows a response of 34.2 dB in the presence of water, a performance which is superior to that seen form other swellable polymeric fibre optic sensors reported so far. Furthermore, the resistance of both sensors to highly alkaline environments (pH 13.4), an important feature of such sensors was verified. Consequently, when compared to the use of conventional inspection techniques, the novel fibre optic sensor system provides a robust, relatively low-cost and continuous monitoring system well suited to use in sewerage tunnels.

show abstract

“…So far, many different non-invasive techniques have been tested [4], but they all have some limitations: some are not applicable in presence of magnetic fields (NMR), others are not capable of detecting small water content variations (gamma and x-rays), their investigation depth is limited (gamma and x-rays, radar based methods), or they need access to both sides of the investigated object (microwave methods) [5]. In recent years, many studies have demonstrated that optoelectronic technologies can be successfully used in several branches of civil engineering [6], including the determination of moisture content in porous media [7][8][9]. One emerging technology exploiting optical fibres is Distributed Temperature Sensing (DTS), a flexible and powerful technique that provides the measurement of the temperature profile along a standard optical fibre with high accuracy and spatial resolution.…”

Section: Introductionmentioning

confidence: 99%

Non-invasive water content estimation in a tuff wall by DTS

Agliata

Bogaard

Greco

et al. 2019

Construction and Building Materials

View full text Add to dashboard Cite

h i g h l i g h t s The sensitivity of a OF-DTS system to water changes in masonry materials is tested. An active DTS setup is used on a testing wall made of yellow Neapolitan tuff bricks. Acquisitions by DTS are coupled with gravimetric measurements of water content. The dependency of the measured temperature on water content is detected. Good thermal contact between cable and wall is crucial for representative readings.

show abstract

Fibre optic humidity sensor designed for highly alkaline environments

Cited by 3 publications

References 5 publications

Innovation in Corrosion Monitoring in Sewers

Innovation in Corrosion Monitoring in Sewers

Sewerage tunnel leakage detection using a fibre optic moisture-detecting sensor system

Non-invasive water content estimation in a tuff wall by DTS

Contact Info

Product

Resources

About