Sensing Technology.
Applications. 2 Basic_Sensing_e.ppt / ad
Laser. LASER λ 0 [nm] Intensity λ [nm] λ 0 3 Basic_Sensing_e.ppt / ad
Rayleigh, Brillouin, Raman Scattering. LASER λ 0 [nm] Rayleigh Intensity Anti Stokes Components T T Raman Brillouin Brillouin Stokes Components T T λ [nm] Raman 4 Basic_Sensing_e.ppt / ad
Optical fiber <> Silicium dioxyde SiO 2. Raman effect Silica: SiO 2 O Si - O Back scattered light AS & S LASER probe 5 Basic_Sensing_e.ppt / ad
Measuring system. Raman effect. For temperature sensing only. Intensity change method. Uses multimode fibres. Cost effective solution for distances up to 8-10 km. Brillouin effect. For Temperature and strain sensing. Frequency shift method. Uses singlemode fibres. For distances up to 30 km and more. Can be combined with singlemode communication transmission. 6 Basic_Sensing_e.ppt / ad
Raman vs. Brillouin sensing techniques. Raman-based temperature sensing. Raman scattering is sensitive only to temperature. Low scattering intensity. Requires multimode optical fibers (high numerical apperture). Very efficient for distances up to 8km distance. Issues related to intensity-based techniques. Availability of multimode fibers? 7 Basic_Sensing_e.ppt / ad
Raman vs. Brillouin sensing techniques. Brillouin-based temperature/strain sensing. Brillouin scattering is sensitive to strain and temperature. Possibilities to be stimulated through dedicated optical processing. Requires singlemode optical fibers. Offers greater distance range (up to more than 30km). Advantage of frequency-based measurement technique. More advanced measurement system. Compatibility with singlemode fiber communication system (sensing can be multiplexed with data transmission. 8 Basic_Sensing_e.ppt / ad
An optical fiber as a sensing element. The DTS is based on the measurement of the Brillouin Scattering characteristics. Natural scattering process associated to the propagation of light. Intrisic properties of the fiber. Interaction of light with the propagation medium. Attributed to the presence of inhomogeneities associated to acoustic waves in the silica (acoustic phonons). Léon Brillouin (1889-1969): French physicist Léon Brillouin pioneered the field of quantum mecanics and solid state physics. He was the first to describe the properties of thermally excited acoustic waves in solids and liquids and their interactions with light, leading to the scattering of light. 9 Basic_Sensing_e.ppt / ad
Methods. Raman for temperature monitoring. Transmitted light Light input Back scattered light Optical fibre Analysis of back scattered spectrum Intensity I s I a T 10 Basic_Sensing_e.ppt / ad
Measuring methods. Raman based temperature measures. Intensity of back scattered laser pulse temperature. Time delay of back scattered laser pulse location. Temperature profile can be recorded and displayed along the whole optical fibre length. 11 Basic_Sensing_e.ppt / ad
Methods. Brillouin for temperature monitoring. Transmitted light Optical fibre Light input Back scattered light Analysis of back scattered spectrum Frequency domain analysis 12 Basic_Sensing_e.ppt / ad
Measuring methods. Brillouin based temperature measures. Frequency shift of back scattered laser pulse temperature. Time delay of back scattered laser pulse location. Temperature profile can be recorded and displayed along the whole optical fibre length. 13 Basic_Sensing_e.ppt / ad
Applications & markets. 14 Basic_Sensing_e.ppt / ad
Applications & markets (general). Oil and gas industries. Pipelines, storage tanks, off-shore platforms, subsea exploration Civil engineering. Structural monitoring (dams, dikes, highways,...). Surveillance and Safety systems. Tunnels, buildings, heating systems, waste disposal sites, power cables, air-con systems, dikes Land slide. Environmental sciences. Telecommunications. Maintenance activities on fiber cables. 15 Basic_Sensing_e.ppt / ad
Advantages of FO temperature monitoring. Continuous, distributed temperature sensing with high resolution along sensor cable. Many possible variants for disposition of the system. Installation possible on location, which are not accessible afterwards (ex. dams). No influence by electro-magnetic fields. Easy installation. No influence of temperature field by process of measure. No active electronic components are necessary (protection against explosion). 16 Basic_Sensing_e.ppt / ad
Temperature monitoring. Temperature monitoring sensor. Robust design. Stainless steel armouring. Up to 8 fibers in SS loose tube. -55 C to 85 C temperature range (standard). -65 C to 300 C temperature range (extreme Temp version). Flame retardant non-corrosive (FRNC) and other sheath options. Stainless steel wires Sheath Stainless steel loose tube Optical fibres 17 Basic_Sensing_e.ppt / ad
Fire Prevention.
Applications. Metro & railway stations. Metro trains. Parking houses. Bus terminals. Airplane hangars. Mining tunnels. Road tunnels. Elevator shafts.
Metro & railway stations.
Metro trains.
Parking houses.
Bus terminals.
Airplane hangars.
Mining tunnels.
Road tunnels.
Heat detection system. Features & benefits. 8 km, 16km and 24km range. Robust and easy to install sensing cables. Automatic unattented operation. Rapid detection and localization of fire. Interface with standard control systems. Automatic generation of alarms signals. Remote control and configuration. 33 Basic_Sensing_e.ppt / ad
Application example. Fire protection in tunnels. Quick detection of hot spots. Detection of location of fire. Coordination of rescue and intervention against fire can be done in a quick and efficient way. 34 Basic_Sensing_e.ppt / ad
Elevator shafts.
Power generation & distribution.
Applications. Power cables in plants & distribution. Transformers in power plants. Power cable tunnels/ducts.
Power cables in plants & distribution.
Transformers in power plants.
Power cable tunnels/ducts.
Process control.
Applications. Pipeline leakage. Monitoring of ovens or storage tanks. Elevator shafts. Metro trains. Conveyor belts. Cold stores.
Pipeline leakage.
Other applications. DTS Leakage Detection System for pipelines, dams, dikes, etc. Features & benefits. Up to 30km distance range. Estension to more than 250 km with a single instrument and DRM. Robust and easy to install sensing cables. Automatic unattented operation. High accuracy temperature monitoring (< 0.5 C) for reliable leak detection. Automatic generation of alarms signals. Remote control and configuration capabilities. 50 Basic_Sensing_e.ppt / ad
Sensing cable installation. Cable installation at the time of the oil pipeline construction. Pipeline construction and sensing cable embedding: The sensing fiber cable is burried in the sand prior to the oil pipeline laying. 51 Basic_Sensing_e.ppt / ad
Pipeline leakage.
Maintenance activities on pipelines. Temperature monitoring during pressure tests on a pipeline. Bi-annual pipeline integrity check. High accuracy temperature monitoring on 15 km sections of pipe. 54 Basic_Sensing_e.ppt / ad
Monitoring of ovens or storage tanks. Reduce costs of maintenance and operation. Intervention can be planned in a perfect way (just in time). 65 70 75 80 85 90 95 100 105 110 115 120 125 2.0 1.0 0.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 56 Basic_Sensing_e.ppt / ad
Elevator shafts.
Metro trains.
Conveyor belts.
Cold stores.
Environmental protection.
Applications. Dams/barrages. Dike dams.
Dams/barrages.
Temp. monitoring in a dam/barrage. Temperture monitoring of the concrete during setting. Overheating introduces microcracks (T > 50 C). dam: 17 m added to the original height of the dam in order to increase the lake capacity. 69 Basic_Sensing_e.ppt / ad
Temp. monitoring in a dam/barrage. Setup of the sensing fiber in the concrete layer (15m x 20m). 70 Basic_Sensing_e.ppt / ad
Temp. monitoring in a dam/barrage. Setup of the sensing fiber in the concrete layer (15m x 20m). 71 Basic_Sensing_e.ppt / ad
Temp. monitoring in a dam/barrage. Temperature evolution over 6 months. 72 Basic_Sensing_e.ppt / ad
Dike dams.
River dikes monitoring advanced erosion warning. Possibility to cover long distances. Possibility to locate erosion problems (early warning) or overflow before catastrophic dike failures. Dike River Dike 75 Basic_Sensing_e.ppt / ad
Geothermal investigations.
Applications. Geothermal drilling.
Geothermal drilling.
Questions, Remarks? 80 Basic_Sensing_e.ppt / ad
Thank you for your attention! 81 Basic_Sensing_e.ppt / ad