Fibers and sensors for monitoring nuclear power plants operation

Solid-state additive manufacturing for metallized optical fiber integration

“…These fibers consisted of two Aluminum-coated optical fibers and two Copper-coated optical fibers with analogous core sizes. Initially developed for ultra-high reliability telecommunications applications, these metallized fibers are also used for ultrahigh temperature monitoring, material fatigue monitoring and down-hole exploration in the oil and gas industry [24,25]. The central silica core sizes of these coated fibers represent the most common commercially available core diameters of uncoated optical fibers.…”

All-Fiber Highly Sensitive Bragg Grating Bend Sensor

“…This measurement principle was used in combined structures of fiber bend sensors meant to control the curvature of the technological channels of an atomic reactor under repair [4], for the early warning of landslides and other geological tasks [5,6]. The principle of measurement using three- and four-core fibers is well described in literature [15,16,17,18,19,20,21].…”

“…However, to increase sensitivity, the sensor has to be installed as far as possible from the central axis of the bend. To measure bend deformations inside channels and pipes, special composite structures have to be designed, based on transducers that convert bending deformations to a linear deformation of the sensors [4,5,6,7,8,9,10] attached to the side surface of the transducer. Such sensor systems allow, for example, to conduct the measurements by inserting the sensing element into the channel of the object under investigation.…”

“…Application of such sensors in the nuclear industry deserve a special mention, namely for monitoring the technological parameters of nuclear reactors. For instance, it is essential to control the curvature of the reactor’s technological channels at high temperatures and increased background radiation [4]. Harsh operating conditions impose severe restrictions on the design of sensors.…”

Method for producing angled optical fiber tips in the laboratory

“…[5][6][7] Specifically for sensors, fibers have the advantage of being small in size and flexible, allowing them to reach remote locations. Their robustness and lack of requirement for electrical power at the sensing site also allow them to find uses including monitoring conditions in coal mines 2 and nuclear power stations 8 to medical blood gas sensing, 9,10 optical coherence tomography, 10 and laser tissue ablation. 7 Traditionally, optical fiber sensors use flat tips, cleaved and polished at 90 deg to the axis of the fiber.…”