A5051390924- Advanced Fiber Optic Sensors
- Photonic and Optical Devices
- Photonic Crystal and Fiber Optics
- Adhesion, Friction, and Surface Interactions
- Semiconductor Lasers and Optical Devices
- Acoustic Wave Resonator Technologies
- Advanced Surface Polishing Techniques
- Structural Health Monitoring Techniques
- Advanced Fiber Laser Technologies
- Advanced MEMS and NEMS Technologies
- Advanced Sensor Technologies Research
- Advanced Sensor and Energy Harvesting Materials
- Silicone and Siloxane Chemistry
Munich University of Applied Sciences
2021-2025
An optical fiber with both temperature and strain Bragg grating sensors were embedded into an aluminum cast structure during the casting process. Temperature calibrations carried out respectively for metal-embedded sensors. external decoupling was further demonstrated in a range from 25 to 80 °C 0 ∼110 µɛ. With interpolated measured by two at different positions, could be decoupled thermal sensor. The values obtained our agreed well reference values, revealing good performance of difference...
In-situ temperature and strain during copper casting process were monitored for the first time based on regenerated fiber Bragg grating (RFBG) sensors, with maximum up to 1100 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{\circ }$</tex-math></inline-formula> C largest compressive approximately −14 000 notation="LaTeX">$\mu$</tex-math></inline-formula>...
In this study, the response of fiber Bragg gratings (FBGs) embedded in cast aluminum parts under thermal and mechanical load were investigated. Several types FBGs different fibers used order to verify general applicability. To monitor a temperature-induced strain, an regenerated FBG (RFBG) part was placed climatic chamber heated up 120 ∘C within several cycles. The results show good agreement with theoretical model, which consists shrink-fit model temperature-dependent material parameters....
Regenerated fiber Bragg gratings (RFBGs) have been created in large mode area (LMA) fibers, and their key properties for application as high-temperature sensors were experimentally characterized. UV written Type-I seed standard single-mode fibers (SMF-28) low numerical aperture LMA with 125 μm 250 cladding diameters regenerated, wavelength drift characteristics at high temperatures, temperature sensitivities, mechanical strengths tested compared each other. We found that dopant...
The high-temperature performance of a sapphire fiber Bragg grating (FBG) has been characterized by commercial single-mode interrogator. By using the mode field matching fusion splicing method, we proposed before, high-order modes in reflection spectrum FBG could be suppressed and quasi-single-mode obtained from fiber-based demodulation system. A 48-h isothermal annealing at 900 °C two temperature calibration processes, one up to 800 another 1200 °C, were carried out successively. There was...
A new calibration methodology for regenerated fiber Bragg grating (RFBG) temperature sensors up to 700 °C is proposed and demonstrated. generalized, wavelength-dependent function experimentally determined that describes the temperature-induced wavelength shifts all RFBG sensor elements are manufactured with same fabrication parameters in range from 1465 nm 1605 nm. Using this generalized absolute measurements, each element only needs be calibrated at one reference temperature, representing a...
The temperature distribution during a metal casting process is important because it influences structural properties and residual stresses of the casted part. In this paper, we report on multipoint monitoring based regenerated fiber Bragg grating (RFBG) array copper process, with maximum exceeding 1100°C. A calibration function up to 800°C was obtained experimentally linearly extended 1200°C. According experimental results, information from an RFBG sensor agreed well that thermocouple...
In recent years, multipoint temperature sensors based on regenerated fiber Bragg gratings have achieved a high degree of maturity. Specific sensor characteristics and applications in metallurgy, gas turbine, aircraft engine instrumentations are reviewed.
We propose and present a high temperature fiber optic sensor based on an intrinsic sapphire Fabry-Pérot interferometer single mode interrogation system for measurements up to 1200°C.
An aluminum embedded fiber Bragg grating (FBG) sensor configuration for a decoupled temperature and strain measurement was proposed demonstrated. This consists of three-point regenerated FBG (RFBG) array with distance 8 mm in one fiber. One RFBG direct contact the aluminum, whereas other RFBGs were protected from by steel capillary. The influenced strain, only temperature. casting mold used here had second symmetric arm an additional reference three Two experiments this made, measurements...
The strain evolution and distribution during an aluminum casting were monitored with regenerated fiber Bragg gratings, showing that the behavior was highly related to solidification characteristics of alloy.
Shaker tests were performed with RFBGs in the range of 0.1 – 10 kHz at 4.5 g acceleration. In successive tests, showed no failures, and vibrations had only a limited influence on measured temperatures.