Pyrometric Method of Temperature Measurement with Compensation for Solar Radiation

2010 ◽  
Vol 17 (1) ◽  
pp. 77-86 ◽  
Author(s):  
Henryk Madura ◽  
Mariusz Kastek ◽  
Tomasz Sosnowski ◽  
Tomasz Orżanowski
Keyword(s):  
Solar Radiation ◽  
Temperature Measurement ◽  
Error Rate ◽  
Thermal Emission ◽  
Infrared Range ◽  
Measured Temperature ◽  
Short Wavelength Band ◽  
Measuring Device ◽  
Long Wavelength ◽  
Spectral Bands

Pyrometric Method of Temperature Measurement with Compensation for Solar RadiationOutdoor remote temperature measurements in the infrared range can be very inaccurate because of the influence of solar radiation reflected from a measured object. In case of strong directional reflection towards a measuring device, the error rate can easily reach hundreds per cent as the reflected signal adds to the thermal emission of an object. As a result, the measured temperature is much higher than the real one. Error rate depends mainly on the emissivity of an object and intensity of solar radiation. The position of the measuring device with reference to an object and the Sun is also important. The method of compensation of such undesirable influence of solar radiation will be presented. It is based on simultaneous measurements in two different spectral bands, shor-twavelength and long-wavelength ones. The temperature of an object is derived from long-wavelength data only, whereas the short-wavelength band, the corrective one, is used to estimate the solar radiation level. Both bands were selected to achieve proportional changes of the output signal due to solar radiation. Knowing the relation between emissivity and solar radiation levels in both spectral bands, it is possible to reduce the measurement error several times.

Surface temperature measurement in the medium and long wavelength infrared range on MAST

2011 ◽  
Vol 415 (1) ◽  
pp. S1178-S1181 ◽  
Author(s):  
E. Delchambre-Demoncheaux ◽  
G. DeTemmerman ◽  
T. Loarer ◽  
E. Gauthier ◽  
G. Dunand ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Temperature Measurement ◽  
Infrared Range ◽  
Surface Temperature Measurement ◽  
Long Wavelength ◽  
Long Wavelength Infrared

scholarly journals Temperature Measurement at Curved Surfaces Using 3D Printed Planar Resistance Temperature Detectors

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1100
Author(s):  
Adam Steckiewicz ◽  
Kornelia Konopka ◽  
Agnieszka Choroszucho ◽  
Jacek Maciej Stankiewicz
Keyword(s):  
Temperature Measurement ◽  
Fused Deposition Modeling ◽  
Numerical Models ◽  
Elastic Base ◽  
Measuring Device ◽  
Fused Deposition ◽  
Influence Of Temperature On ◽  
Printed Sensors ◽  
Analytical Formulae ◽  
3D Printed

In this article, novel 3D printed sensors for temperature measurement are presented. A planar structure of the resistive element is made, utilizing paths of a conductive filament embedded in an elastic base. Both electrically conductive and flexible filaments are used simultaneously during the 3D printing procedure, to form a ready–to–use measuring device. Due to the achieved flexibility, the detectors may be used on curved and irregular surfaces, with no concern for their possible damage. The geometry and properties of the proposed resistance detectors are discussed, along with a printing procedure. Numerical models of considered sensors are characterized, and the calculated current distributions as well as equivalent resistances of the different structures are compared. Then, a nonlinear influence of temperature on the resistance is experimentally determined for the exemplary planar sensors. Based on these results, using first–order and hybrid linear–exponential approximations, the analytical formulae are derived. Additionally, the device to measure an average temperature from several measuring surfaces is considered. Since geometry of the sensor can be designed utilizing presented approach and printed by applying fused deposition modeling, the functional device can be customized to individual needs.

scholarly journals Infrared Spectroscopy of Jupiter and Saturn

2002 ◽  
Vol 12 ◽  
pp. 96-98
Author(s):  
Pierre Drossart
Keyword(s):  
Remote Sensing ◽  
Infrared Spectroscopy ◽  
Thermal Emission ◽  
Temporal Evolution ◽  
Imaging Spectroscopy ◽  
Giant Planets ◽  
Infrared Range ◽  
Physical Parameters ◽  
Temperature Structure ◽  
Reflected Light

AbstractThe spectroscopy of giant planets in the infrared range gives access to a remote sensing of many physical parameters. The composition, pressure/temperature structure, and the cloud structure all contribute to the spectrum, in solar reflected light below 3 micrometer as well as thermal emission above, from atmospheric levels ranging from the mesosphere down to the troposphere. Imaging spectroscopy revealing the variability of the atmosphere gives access to spatial and temporal evolution of these parameters, constraining the meteorological evolution of the planets.

Solar Radiation at 1200 MC/S., 600 MC/S., and 200 MC/S

1949 ◽  
Vol 2 (1) ◽  
pp. 48 ◽  
Author(s):  
FJ Lehany ◽  
DE Yabsley
Keyword(s):  
Magnetic Field ◽  
Body Temperature ◽  
Solar Radiation ◽  
Thermal Emission ◽  
Black Body ◽  
Sunspot Area ◽  
The Sun ◽  
Long Period ◽  
Period Variations ◽  
The Magnetic Field

Daily observations of solar radiation at frequencies of 1200 Mc/s., 600 Mc/s., and 200 Mc/s. taken between August 18 and November 30, 1947, are described. The characteristics of the radiation at 200 Mc/s. were in general agreement with those observed by earlier workers. At 600 Mc/s. and 1200 Mc/s., the received intensity was normally steady on any one day but underwent long-period variations over a range of about two to one. The radiation received when the sun was almost free of sunspots corresponded to an effective black-body temperature of 0.5 million �K. at 600 Mc/s. and 0.1 million �K. at 1200 Mc/s. As sunspots appeared, the temperature rose and showed marked oar- relation with sunspot area. It is considered that radiation at these frequencies is entirely thermal in origin and that the long-period variations are at least partly due to the influence of the magnetic field of sunspots on the mechanism of thermal emission from a magneto-ionic medium. On a few occasions, isolated disturbances were observed on 600 Mc/s. and 1200 Mc/s. some of which were associated with chromospheric flares and radio fade-outs. The difficulties arising in the calibration of the apparatus and the steps taken to overcome them are discussed in detail.

scholarly journals Influence of Size of Source Effect on Accuracy of LWIR Radiation Thermometers

2016 ◽  
Vol 23 (4) ◽  
pp. 661-667
Author(s):  
David Cywiak ◽  
Daniel Cárdenas-García ◽  
Hugo Rodriguez-Arteaga
Keyword(s):  
Radiation Thermometer ◽  
Electrical Signal ◽  
Field Of View ◽  
Measured Temperature ◽  
Temperature Deviation ◽  
Source Effect ◽  
Long Wavelength ◽  
Proposed Model ◽  
Long Wavelength Infrared ◽  
Infrared Radiation Thermometer

Abstract Determining the size of source effect of a radiation thermometer is not an easy task and manufacturers of these thermometers usually do not indicate the deviation to the measured temperature due to this effect. It is one of the main uncertainty components when measuring with a radiation thermometer and it may lead to erroneous estimation of the actual temperature of the measured target. We present an empiric model to estimate the magnitude of deviation of the measured temperature with a long-wavelength infrared radiation thermometer due to the size of source effect. The deviation is calculated as a function of the field of view of the thermometer and the diameter of the radiating source. For thermometers whose field of view size at 90% power is approximately equal to the diameter of the radiating source, it was found that this effect may lead to deviations of the measured temperature of up to 6% at 200ºC and up to 14% at 500ºC. Calculations of the temperature deviation with the proposed model are performed as a function of temperature and as a function of the first order component of electrical signal.

Magnetooptical Studies and Stimulated Emission in Narrow Gap HgTe/CdHgTe Structures in the Very Long Wavelength Infrared Range

2018 ◽  
Vol 52 (4) ◽  
pp. 436-441
Author(s):  
V. V. Rumyantsev ◽  
L. S. Bovkun ◽  
A. M. Kadykov ◽  
M. A. Fadeev ◽  
A. A. Dubinov ◽  
...  
Keyword(s):  
Stimulated Emission ◽  
Infrared Range ◽  
Narrow Gap ◽  
Long Wavelength ◽  
Long Wavelength Infrared

scholarly journals GF-5 Hyperspectral Data for Species Mapping of Mangrove in Mai Po, Hong Kong

2020 ◽  
Vol 12 (4) ◽  
pp. 656 ◽  
Author(s):  
Luoma Wan ◽  
Yinyi Lin ◽  
Hongsheng Zhang ◽  
Feng Wang ◽  
Mingfeng Liu ◽  
...  
Keyword(s):  
Hong Kong ◽  
Spectral Resolution ◽  
Hyperspectral Data ◽  
Support Vector ◽  
Species Discrimination ◽  
Infrared Range ◽  
Landsat 8 ◽  
Mangrove Species ◽  
Spectral Bands ◽  
Species Mapping

Hyperspectral data has been widely used in species discrimination of plants with rich spectral information in hundreds of spectral bands, while the availability of hyperspectral data has hindered its applications in many specific cases. The successful operation of the Chinese satellite, Gaofen-5 (GF-5), provides potentially promising new hyperspectral dataset with 330 spectral bands in visible and near infrared range. Therefore, there is much demand for assessing the effectiveness and superiority of GF-5 hyperspectral data in plants species mapping, particularly mangrove species mapping, to better support the efficient mangrove management. In this study, mangrove forest in Mai Po Nature Reserve (MPNR), Hong Kong was selected as the study area. Four dominant native mangrove species were investigated in this study according to the field surveys. Two machine learning methods, Random Forests and Support Vector Machines, were employed to classify mangrove species with Landsat 8, Simulated Hyperion and GF-5 data sets. The results showed that 97 more bands of GF-5 over Hyperion brought a higher over accuracy of 87.12%, in comparison with 86.82% from Hyperion and 73.89% from Landsat 8. The higher spectral resolution of 5 nm in GF-5 was identified as making the major contribution, especially for the mapping of Aegiceras corniculatum. Therefore, GF-5 is likely to improve the classification accuracy of mangrove species mapping via enhancing spectral resolution and thus has promising potential to improve mangrove monitoring at species level to support mangrove management.

Dual Wavelength Temperature Monitoring of TBC Coated Alstom 13E2 Turbine Blades

2003 ◽  
Author(s):  
R. A. Rooth ◽  
W. Hiemstra
Keyword(s):  
Temperature Measurement ◽  
Gas Turbine ◽  
Turbine Blades ◽  
Temperature Measurements ◽  
Primary Interest ◽  
Long Wavelength ◽  
Work Related ◽  
Fiber Technology ◽  
Measurement Results ◽  
First Time

Through rapid developments in fiber technology and data acquisition technology, pyrometry has become a successful tool for the measurement of gas turbine blade temperatures. The technology enables gas turbine owners and operators to monitor the blades and to optimise the exploitation of their assets in terms of efficiency and maintenance. With the application of thermal barrier coatings on turbine blades, pyrometry faces a new challenge as these coatings are not opaque at commonly used wavelengths. The application of TBC’s to protect the metal blades allows an increase of the firing temperature, increasing the efficiency of the installation, but is potentially an additional cause of locally overheating blades in the case the coating comes off. The present paper reports on the results of experimental work related to the temperature measurement on an in service Alstom 13E2 turbine with TBC coated first stage blades. Temperature measurements have been performed with both short- and long wavelength instruments (1 μm and 10 μm). The optical characteristics of ZrO2 material at a range of temperatures have been determined. These characteristics are important in the implementation of an algorithm that calculates the metal temperature from the temperature measurement results. These metal temperatures are of primary interest, This is the first time that experimental radiation temperature measurements on an industrial turbine, using both 1 and 10 μm technology, are reported. As the measurement trace over the turbine airfoil consists of areas on the blade that are covered with TBC as well as uncovered areas, a very interesting comparison on the merits of the various systems can be presented.

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