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