Led was 10 hz, and the frame rate of the high speed camera was 8000 fps. Phosphor thermometry is a term describing an optical measurement technique for. However, this technique is not vulnerable to the issues of pyrometers, thermocouples, thermal paints, and many other thermal sensors. Simultaneous measurements of phosphor thermometry and piv. Noncontact and instant detection of phosphor temperature in phosphorconverted white leds.
Yag laser with a pulse duration of 25 ns and a pulse energy of 1. Application of phosphor thermometry to a galvanneal temperature measurement system david l. These advantages include a measurement of temperature by transfer to measurement standards for time, b remote sensing for surface thermometry, c high speed of measurement relative to many physical and mechanical phenomena, d narrowspectrum optical sensing suitable. Eu phosphors for white leds prepared by the gasreductionnitridation method free pdf. Laserinduced phosphorescence for surface thermometry in. With increasing temperature, the wide emission band exhibits a pronounced blue shift, which can be exploited for temperature imaging using a twocolour. Highspeed planar thermometry and velocimetry using thermographic phosphor particles highspeed planar thermometry and velocimetry using thermographic phosphor particles abram, christopher. Pdf phosphor thermometry techniques for the realization of. Oct 27, 2011 this contribution reports on the first realisation of a high speed phosphor thermometry system employing a highly repetitive laser in the khz regime and a fast decaying phosphor.
Phosphor thermometry is a semiinvasive surface temperature measurement technique utilising the luminescence properties of doped ceramic. Review article remote thermometry with thermographic. Development of new phosphors for high temperature thermometry. Somewhat confusingly, this includes both phosphorescent materials, which show a slow decay in brightness 1ms, and fluorescent materials, where the emission decay takes place over tens of nanoseconds. The application of laser measurement techniques to. Noncontact and instant detection of phosphor temperature in. Dy is a wellknown thermographic phosphor suitable for high temperature measurements.
The use of high speed cameras for quantitative measurements has previously been investigated using a similar camera of an earlier generation photron sa1. Phosphorescent materials are known for their use in radar screens and glowinthedark materials, whereas fluorescent. Photomultipliers and highspeed camera systems are used to transiently detect the subsequently emitted luminescence decay. Phosphor thermometry is another noncontact technique that uses optical signals to measure temperature remotely. Typical examples include centrifuges, turbine engine components, high speed motors, radioactive or very high temperature environments, or vibrating or. The fast, efficient tracer permits precise temperature measurements at khz rates, despite the low pulse energy of highspeed 355 nm lasers. This paper documents the application of high speed phosphor thermometry to measure cylinder head temperatures under fired engine conditions. Mn phosphor and an led excitation source to measure the temperature distribution on a heated aluminium.
Highspeed planar thermometry and velocimetry using. The principles, characteristics, recent progresses and advantages of the technology are described. This paper discusses the currently available techniques for 2d phosphor thermometry, and compares the performance of two lifetimebased methods. Influence of codoping on the luminescence properties of. The nist thermodynamic metrology group maintains and develops national standards of temperature in the range 0. An excitation source is used to excite the phosphor that is bonded onto the surface of interest. A suitable material was characterised regarding its temperature lifetime characteristic and its measurement precision. In this work, the phosphors osram phosphor sv 067 n magnesium. This paper documents the application of highspeed phosphor thermometry to measure cylinder head temperatures under fired engine conditions. The luminescence emission intensity at 300 k is on the order of 106 photons per particle and the lifetime is 26. Next, it outlines the several advantages of fluorescence thermometry. Phosphors are composed of a ceramic lattice doped with a small amount of luminescent ions and will. Influence of codoping on the luminescence properties of yag.
A thermometer is a device that measures temperature or a temperature gradient. Mar 29, 20 high speed planar thermometry and velocimetry using thermographic phosphor particles high speed planar thermometry and velocimetry using thermographic phosphor particles abram, christopher. Osa highprecision flow temperature imaging using zno. Heyes,4 and frank beyrau 2 1department of mechanical engineering, imperial college london, london sw7 2az, uk. Figure 1 shows the experimental setup for highspeed thermographic piv. Noncontact and instant detection of phosphor temperature.
Development of phosphor thermometry systems for use in. Development of the phosphor thermometry technique for. Twodimensional thermographic phosphor thermometry using a. Based on the work of heyes, who developed a method to design phosphors for high temperature, at the moment yag. Nonlinearity was found to increase with increasing signal and to be phosphor thermometry is an optical method for surface temperature measurement. To achieve this aim the numerical model must contain all the resolvable scalesin the. Up to now, primarily qswitched laser systems with repetition rates of 10 hz were employed for excitation. High speed imaging resolves luminescent decay with a fast frame rate, and has become a popular method for phosphor thermometry in recent years. The method exploits luminescence emitted by phosphor material. Archived from the original pdf on 20 september 2016. The phosphor thermometry was applied to measure the temperature. The fast, efficient tracer permits precise temperature measurements at khz rates, despite the low pulse energy of high speed 355 nm lasers. The phosphor thermometry utilizes temperaturedependent luminescence.
Osa investigation of the tindoped phosphor sr,mg3po4. Phosphor physics thermographic phosphors for high temperature applications consist of a ceramic host material doped with rareearth ions lanthanides at concentrations typically between 1%. Transient thermometry intensity ratios are attractive for measurement of systems where surface temperature is changing rapidly. By utilizing highspeed piv measurements, the objective of this study is to examine the performance of an algebraic equilibrium wallfunction model that has been widely employed in rans and les icengine simulations 14. Using spatially and temporally isothermal conditions in a tube furnace, a temperature lifetime characteristic was determined for the. Accuracy and precision of highspeed phosphor thermometry. Intensities can be followed continuously and ratioed to give time dependent temperatures. Jun 27, 2009 in the present study, a cmos high speed camera system was employed for twodimensional thermographic phosphor thermometry. Development staff members research professor oak ridge national laboratory university of virginia oak ridge, tn 378318058 charlottesville, va. Phosphor thermometry is a temperature measurement approach that uses the temperature dependence of certain phosphors for this purpose. Phosphor thermometry is a semiinvasive surface temperature measurement technique utilising the luminescence properties of doped ceramic materials. A brief history of phosphor thermometry advanced energy. Dy is the phosphor with the highest capability for thermometry at high temperatures. May 17, 2012 twodimensional thermographic phosphor thermometry using a cmos high speed camera system 27 june 2009 applied physics b, vol.
After excitation through a short uv laser pulse, a luminescence fig 2. Using spatially and temporally isothermal conditions in a tube furnace, a temperature lifetime characteristic was determined for the phosphor mg4fgeo6. Many phosphors tend to lose efficiency gradually by several mechanisms. Phosphor physics thermographic phosphors for high temperature applications consist of a ceramic host material doped with rareearth ions lanthanides at concentrations typically between 1% and 10%. Gap phosphor that makes these measurements possible at turbine engine temperatures is the exceptionally high strength. Sep 10, 20 phosphor thermometry is a semiinvasive surface temperature measurement technique utilizing the luminescence properties of thermographic phosphors.
The use of highspeed cameras for quantitative measurements has previously been investigated using a similar camera of an earlier generation photron sa1. By the pixelwise evaluation of the luminescence lifetimes, a temperature map of a phosphor layer can be obtained. Simultaneous measurements of phosphor thermometry and piv for hightemperature gas flows 2015012002 this study reports a novel alternative technique that can achieve simultaneous twodimensional temperature and velocity measurements in gas flow. Thermographic laser doppler velocimetry using the phase. The effects of codoping on the temperaturedependent luminescence of yag.
Pdf the possibility of using singlecrystals of thermographic phosphors in a new realization of the. Thermographic laser doppler velocimetry using the phaseshifted luminescence of bam. Development and analysis of wall models for internal. Hightemperature phosphor thermometry of rotating turbine. A generic phosphor thermometry system comprises of components illustrated in figure 5.
Highspeed planar thermometry and velocimetry using thermographic phosphor particles article pdf available in applied physics b 1112 may 20 with 5 reads how we measure reads. Such a phosphor consists of a host material and a doping agent from which the light is emitted. The beam was expanded using a galilean telescope and then formed into a 600. Imaging phosphor thermometry from t 20 c to 450 c using. Implementation of an ultrabright thermographic phosphor. Review on an advanced hightemperature measurement technology. Calibration measurements are given in the first section, providing the temperature.
Typically these ceramic materials are coated onto the object of interest and are excited by a short uv laser pulse. Application of phosphor thermometry to a galvanneal. Flow measurements are used to compare the temperature precision of zno to that obtained using a wellcharacterised thermographic phosphor, bam. Tpt thermographic phosphor thermometry v velocity vector df d doppler shift of light l wavelength of light 1 introduction the ultimate goal of the aerodynamicist is to solve the navierstokes equations for turbulent. Thermographic phosphors for high temperature measurements. The phosphor particles used in thermometry are usually inorganic materials having the form of a whitebrown powder some 1 10 m in diameter. Lifetimebased phosphor thermometry of an optical engine. Phosphors are fine white or pastelcolored inorganic powders which may be stimulated by any of a variety of means to luminesce, i. Phosphor thermometry techniques for the realization of thermal standards. The sensors include a light source that emits an excitation light through one or more optical fibers to one or more phosphors that produce fluorescent emissions when engaged by the excitation light. Consideration factors 1 july 2010 proceedings of the institution of mechanical engineers, part g. High speed thermographic particle image velocimetry. Phosphor thermometry is a semiinvasive surface temperature measurement technique utilizing the luminescence properties of thermographic phosphors.
Many blackbody, infrared, and fluorescence optical thermometers are developed for practical applications. Thermometry thermometry is the science and practice of temperature measurement. The activators can undergo change of valence usually oxidation, the crystal lattice degrades, atoms often the activators diffuse through the material, the surface undergoes chemical reactions with the environment with consequent loss of efficiency or buildup of a layer absorbing either the. Typically, these phosphor materials are coated onto the object of interest and are excited by a short uv laser pulse. Mn phosphor and an led excitation source to measure the temperature distribution on a. Typical examples include centrifuges, turbine engine components, high speed motors, radioactive or very high temperature environments, or vibrating or moving production machinery. Vacuum light sources high speed stroboscopic light sources data sheet pdf. Pdf highspeed planar thermometry and velocimetry using. Photomultipliers and high speed camera systems are used to transiently detect the subsequently emitted luminescence decay point wise. Zinc oxide zno particles are characterised as a tracer for temperature measurements in turbulent flows, in the context of the thermographic particle image velocimetry technique. Childs oak ridge national laboratory oak ridge, tennessee 378318058 joe vehec advanced. The fundamental principles and theory are presented, and the various spectral and temporal modes, including the lifetime decay, rise time and intensity ratio, are discussed. In situ contactless thermal characterisation and imaging. If hightimeresolution temperature measurements can be performed using a phosphor and a highspeed camera, it will be straightforward to combine phosphor thermometry with the abovementioned temperature and velocity measurement system by using phosphor particles as.
However, its decay time is too long for studying temperatures in fast transient technical processes. Oct 30, 20 this paper documents the application of high speed phosphor thermometry to measure cylinder head temperatures under fired engine conditions. Mar 29, 20 accuracy and precision of high speed phosphor thermometry. Yi et al 6, 7 utilise a highspeed camera 4000 fps, mg 4fgeo 6. Sec tion vii compares the performance of phosphor thermometry with that of. Nonlinearity was found to increase with increasing signal and to be 1 ms, and fluorescent materials, where the emission decay takes place over tens of nanoseconds. The photoluminescence properties of the phosphor sr,mg3po42. Dy were investigated for application in high temperature thermometry. For this, a phosphor coating is applied to a surface of interest and, usually, the decay time is the emission parameter that indicates temperature. Fluorogermanate, manganaktiviert, lot 48 were mixed with a high. Also, phosphor may be applied to the end of an optical fiber as an optical analog of a thermocouple.
In the present study, a cmos high speed camera system was employed for twodimensional thermographic phosphor thermometry. A large number of different phosphors are produced today. For thermometry, the phosphor particles were excited using the third harmonic of a diode pumped nd. The history of phosphor thermometry in the authors opin ion falls into three. Comparison of lifetimebased methods for 2d phosphor. Phosphorescent materials are known for their use in radar screens and glowinthedark toys, whereas. Jan 10, 2018 noncontact and instant detection of phosphor temperature in phosphorconverted white leds. A phosphor, most generally, is a substance that exhibits the phenomenon of luminescence.
Unknown parameter deadurl ignored seeing phosphor bands on u. Phosphor thermometry techniques for the realization of. Cylinder head temperature determination using highspeed. Cr,ce was synthesized with a special composition to meet the requirements of the measurement technique and the device under test. High precision phosphor temperature sensors are disclosed. The application of laser measurement techniques to aerospace. Jun 11, 2019 in this work, the phosphors osram phosphor sv 067 n magnesium.