Optical Fiber Sensor boosts aircraft engine monitoring

A reflective, intensity-modulated optical fiber sensor enables monitoring of tip clearance and tip timing in aircraft engines at low cost and high resolution.This work has been sponsored by the institutions Ministerio de Economía y Competitividad under project TEC2012-37983-C03; Gobierno Vasco/Eusko Jaurlaritza under projects IT664-13, S-PE13CA004, SPE13UN151, and S-PE12CA001; and by the University of the Basque Country (UPV/EHU) through program UFI11/16.Publicatio

Plastic fiber-optic probes for characterizing fluidized beds in bubbling regime

Bubble measurements on a fluidized bed in bubbling regime using optical fibre probes (OFP) are reported. Comparisons between commercial pressure transducers (PT) measurements and OFP have also been carried out. OFP are able to detect smaller bubbles than the PT and reflect more localized phenomena in the bed.Publicad

Polymer Optical Fiber Temperature Sensor With Dual-Wavelength Compensation of Power Fluctuations

The design and development of a plastic optical fiber macrobend temperature sensor is presented. The sensor can operate in a temperature range from -55 to 70 degrees C and has a linear response versus temperature with a sensitivity of 8.95.10(-4) degrees C-1. The sensor system uses the ratio of transmittance at two wavelengths to implement a self-referencing technique in order to avoid undesirable power fluctuations influence. The transmittance ratio precision is 0.1%. An analysis has been developed to find the two wavelengths which ratio offers the highest linearity and sensitivity response. Experimental results are successfully compared with theoretical approaches.This work was supported by the Spanish Ministry of Economía y Competitividad and Madrid region under Grants TEC2012–37983-C03–02, P2013/MIT-2790.Publicad

Self-referenced temperature sensor based on a polymer optical fiber macro-bend

This proceeding at : 23 rd International Conference en Optical Fiber Sensors (OFS23). Took place in 2014, June, 02-06, in Santander (Spain).The design and development of a plastic optical fiber (POF) macrobend temperature sensor is presented. The sensor has a linear response versus temperature at a fixed bend radius, with a sensitivity of 8.2 ∙ 10−4(ºC)−1 〖8.2.10〗^(-4) 〖(°C) 〗^(-1) and a 8% non-linearity full scale error. The sensor system uses the power variation between two discrete wavelengths for auto reference purposes. An analysis for selecting operation wavelengths has been carried out in order to optimize the response of the sensor. The proposed sensor can be used in harsh environment and has a low-costThis work has been sponsored by the Spanish Ministry of Economía y Competitividad under grant TEC2012-37983-C03-02.Publicad

One photon and two photon spectroscopy in polymer optical fibres doped with conjugated polymer

The proceeding at: 22nd International Conference on Plastic Optical Fibers (POF 2013), took place in 2013 September,11-13, in Armação dos Buzios, Rio de Janeiro, (Brasil). The event Web site at: http://www.pof2013.org.br/ .In this work, we have compared the characteristics of the spectral emission of plastic optical fibers (POFs) doped with the conjugated polymer poly(9,9 dioctylfluorene)-alt-benzothiadiazole (F8BT), under oneand two-photon excitation. Measurements include evolutions of the fluorescence spectra with excitation wavelength and propagation distance, together with an analysis of the emission photostability.This work has been sponsored by the institutions Ministerio de Economía y Competitividad under projects TEC2009-147-C03-01, TEC2012-37983-C03-01, Gobierno Vasco/Eusko Jaurlaritza under projects AIRHEM-II, S-PE12CA001, IT664-13, and by the University of the Basque Country (UPV/EHU) through program UFI11/16.Publicad

Use of a novel fiber optical strain sensor for monitoring the vertical deflection of an aircraft flap

The present paper reports the use of a plastic optical fiber-based sensor for elongation measurements in an aircraft flap subjected to different types of flexural loading conditions. The sensor, bonded to the surface of the aircraft structure, relies on measuring the phase shift that occurs between two sinusoidally modulated light signals when the aircraft structure is bent. The light signals are guided through two optical fibers, one of them fixed to the top surface of the flap, and the other one to the bottom surface. The sensor offers good signal stability and repeatability and represents a cost-effective alternative to other more sophisticated health-monitoring systems currently used.Publicad

Polimerozko zuntz optiko dopatuen erabilera laser eta anplifikagailu gisa

This paper analyzes the peculiarities of light amplification in doped polymer optical fibres (POFs) by using our computational model under diverse conditions. Specifically, the influence of the numerical aperture and of the radial distribution of the dopant in the fibre, on the one hand, and the most convenient temporal width of the pump pulse, on the other hand, are investigated. Analyses are carried out for both step-index and graded-index POFs. The results presented correspond to fibres excited longitudinally with short light pulses of several energies.; Artikulu honetan, gure eredu konputazionalaren bitartez, argi-anplifikazioaren ezaugarriak aztertu dira dopaturiko polimerozko zuntz optikoetan (PZOetan). Hain zuzen ere, zenbakizko irekiduraren eta dopantearen distribuzio erradialaren eraginaz gain, ponpaketaren denborazko pultsu-zabalera egokiena ere ikertu da. Analisi hauek guztiak maila-indize eta indize gradualeko PZOentzat egin dira. Lorturiko emaitzak energia desberdinetako argi-pultsuen bitartez longitudinalki kitzikaturiko zuntz aktiboetan oinarritzen dira

Multiparameter sensor based on a chaotic fiber-ring resonator

A new kind of fiber-optic sensor, to our knowledge, is proposed: a chaotic sensor. The sensor is based on a fiber-ring resonator that is optically driven by a train of pulses whose period equals the round-trip delay of the resonator. This sensor exploits the extremely high dependence of chaotic systems on initial conditions to sense several physical parameters (elongation, attenuation, index of refraction). The measured information is encoded in different geometrical characteristics of the chaotic attractor. The proposed sensing scheme has been modeled and simulated. The simulations reveal high potential for this structure as a multiparameter sensor