Temperature monitoring is essential in a wide range of industrial and commercial applications. Traditionally, electric temperature sensors called thermocouples have been used but they have one very significant disadvantage: they measure temperature at only one discrete point. This is inadequate to create an average temperature distribution across the length of the material being measured. Any process in which temperature has to be measured accurately will involve more than one sensor, making measurements more complicated.
A Fiber Optic Temperature Sensor provides continuous temperature measurements along its entire length with spatial resolution as high as 1.6 mm. In contrast, the measurements from conventional sensors are at isolated points. Distributed sensing by fiber optic sensing systems (FOSS) allows the monitoring of thousands of points with one sensing fiber, providing far more insight into the distribution of temperatures.
Several key considerations should be made before installing a fiber optic temperature sensor. Firstly, fiber temperature sensitivity is necessary to eliminate mechanical stress and ensure the proper reading of the temperature. FOSS interrogators operate on changes in the core refractive index and thermally induced strain in determining the temperature reading. Minimizing the mechanical stress component enables apparent strain to result from the change in temperature alone. Coating effects are also heavily responsible for the sensor performance. Stiff polymer coatings, such as polyimide and Ormocer, are commonly used for sensor durability but are hygroscopic, causing the material to expand with absorbed moisture, leading to humidity-dependent hysteresis. Softer coatings like Ormocer-T are thus more suitable for temperature sensing to reduce these inaccuracies.
Sensor preparation is an important factor in achieving accuracy for distributed temperature sensing. Before installing the fiber, it needs to be conditioned to pre-condition the fiber for its likely operating temperature range. Packing serves to isolate the fiber from mechanical strain, a typical strategy being to house it within a capillary tube or similar structure. The installation has to be designed with care to limit friction effects and mechanical strain that may distort temperature measurements. Calibration is also necessary and depends on reference devices like thermocouples or resistance temperature detectors (RTDs) for an accurate measurement.
The Fiber Optic Temperature Sensor has revolutionized many industries by providing real-time thermal mapping and continuous monitoring of temperature gradients. They work well in areas where conventional sensors are not effective, such as in complex geometries or in the presence of electromagnetic interference. The benefits of this technology are particularly appreciated in aerospace, heat exchanger, and composite part manufacturing applications where precise temperature control is critical. Thus, with this solution overcoming the limitations of single-point sensors, robust fiber optic temperature sensors help to improve operational safety and efficiency. For more information, visit: https://www.sensuron.com/