Uncertainty of Thermographic Temperature Measurement with an Additional close-up Lens

Abstract The thermographic temperature measurement is burdened with uncertainty. This non-contact temperature measurement method makes it possible to measure the temperature of the electrical device under load. When the observed object is small (a few square millimeters) the spatial resolution of the thermographic cameras is often insufficient. In this case, the use of the additional macro lens is needed. After using an additional lens, the uncertainty of the thermographic measurement is different from the uncertainty of thermographic measurement without an additional lens. The values of the uncertainty contributions depend on the conditions during the measurement and the used methodology. The authors constructed an uncertainty budget of thermographic temperature measurement with an additional macro lens, based on EA-4/02 (European Accreditation publications). The uncertainty contributions were also calculated. On the basis of the calculated values of the uncertainty contributions, it was determined which factor had the greatest impact on the value of the thermographic temperature measurement with an additional lens.

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Lack of Thermogram Sharpness as Component of Thermographic Temperature Measurement Uncertainty Budget

Sensors ◽

10.3390/s21124013 ◽

2021 ◽

Vol 21 (12) ◽

pp. 4013

Author(s):

Krzysztof Dziarski ◽

Arkadiusz Hulewicz ◽

Grzegorz Dombek

Keyword(s):

Measurement Uncertainty ◽

Temperature Measurement ◽

Uncertainty Budget ◽

Expanded Uncertainty ◽

European Accreditation ◽

Uncertainty Component ◽

Number Of Components ◽

B Method ◽

Thermographic Measurement ◽

Measurement Uncertainty Budget

The number of components of a thermographic temperature measurement uncertainty budget and their ultimate contribution depend on the conditions in which the measurement is performed. The acquired data determine the accuracy with which the uncertainty component is estimated. Unfortunately, when some factors have to be taken into account, it is difficult to determine the value of the uncertainty component caused by the occurrence of this factor. In the case of a thermographic temperature measurement, such a factor is the lack of sharpness of the registered thermogram. This problem intensifies when an additional macro lens must be used. Therefore, it is decided to commence research to prepare an uncertainty budget of thermographic measurement with an additional macro lens based on the B method described in EA-4/02 (European Accreditation publications). As a result, the contribution of factors in the uncertainty budget of thermographic measurement with additional macro lens and the value of expanded uncertainty were obtained.

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The effect of surface observation angle on accuracy of non-contact temperature measurement method

Technology audit and production reserves ◽

10.15587/2312-8372.2017.92869 ◽

2017 ◽

Vol 1 (2(33)) ◽

pp. 19-22

Author(s):

Gennady Oborsky ◽

Aleksandr Levinskiy ◽

Maryna Holofieieva

Keyword(s):

Temperature Measurement ◽

Measurement Method ◽

Contact Temperature ◽

Observation Angle ◽

Surface Observation ◽

Effect Of Surface

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Uncertainty of Thermographic Temperature Measurement of Electric Units Contained in Switchgear

Pomiary Automatyka Robotyka ◽

10.14313/par_242/31 ◽

2021 ◽

Vol 25 (4) ◽

pp. 31-36

Author(s):

Krzysztof Dziarski ◽

Arkadiusz Hulewicz

Keyword(s):

Temperature Measurement ◽

Measurement System ◽

Infrared Radiation ◽

Low Voltage ◽

Uncertainty Budget ◽

Determination Method ◽

Type B ◽

European Accreditation ◽

Camera Lens ◽

Uncertainty Determination

The result of the works presented is the uncertainty budget of a thermographic temperature measurement taken through an IR window. The type B uncertainty determination method has been employed. Publication of European Accreditation EA-4/02 has been patterned. Conditions prevailing in course of the thermographic temperature measurement of low-voltage electric units contained in the switchgear were recreated as part of the works. The measurement system has been presented. Components of the infrared radiation reaching the camera lens in case when an IR window was used and when an IR window was not used have been discussed. Uncertainties estimated for the measurement done with an IR window and without an IR window have been compared.

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Machining Mechanism of Minimum Quantity Lubrication Grinding

Enhanced Heat Transfer Mechanism of Nanofluid MQL Cooling Grinding - Advances in Chemical and Materials Engineering ◽

10.4018/978-1-7998-1546-4.ch003 ◽

2020 ◽

pp. 43-75

Keyword(s):

Temperature Measurement ◽

Measurement Method ◽

Sliding Friction ◽

Minimum Quantity Lubrication ◽

Grinding Force ◽

Contact Temperature ◽

Grinding Process ◽

Machining Mechanism ◽

Constant Cutting Force ◽

Thermocouple Temperature

To facilitate the analysis of experimental theory, this chapter studied the machining mechanism related to the grinding of NMQL and the three mechanisms of sliding, ploughing, and cutting of the abrasive grinding process. A mathematical model of the micro-grinding force was established, and the micro-grinding force can be used to express the force of the grinding zone. The grinding force component was divided into the force of cutting and sliding, removing the constant cutting force during the grinding process, retaining the varying sliding friction force, and determining the sliding friction coefficient to characterize the lubrication performance. It reflected the influence of different lubrication conditions on the friction part. The methods for measuring the temperature during grinding were introduced, including direct contact temperature measurement and non-contact temperature measurement. At present, thermocouple temperature measurement is a commonly used and more accurate temperature measurement method, and the characteristics of each temperature measurement method were analyzed.

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Non-contact temperature measurement method for dynamic rating of overhead power lines.

Electric Power Systems Research ◽

10.1016/j.epsr.2020.106392 ◽

2020 ◽

Vol 185 ◽

pp. 106392 ◽

Cited By ~ 3

Author(s):

Ramón Lecuna ◽

Pablo Castro ◽

Mario Manana ◽

Alberto Laso ◽

Rodrigo Domingo ◽

...

Keyword(s):

Temperature Measurement ◽

Measurement Method ◽

Contact Temperature ◽

Power Lines ◽

Overhead Power Lines

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Sequential dual Kalman filtering approach for non-contact temperature measurement in real-time PCR instrument

JOURNAL OF ELECTRONIC MEASUREMENT AND INSTRUMENT ◽

10.3724/sp.j.1187.2011.00564 ◽

2011 ◽

Vol 25 (6) ◽

pp. 564-572 ◽

Cited By ~ 1

Author(s):

Xuhai Chen ◽

Min Du

Keyword(s):

Temperature Measurement ◽

Real Time ◽

Kalman Filtering ◽

Real Time Pcr ◽

Contact Temperature ◽

Filtering Approach

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Enhancement of Strain/Temperature Measurement Range and Spatial Resolution in Brillouin Optical Correlation Domain Analysis Based on Convexity Extraction Algorithm

IEEE Access ◽

10.1109/access.2019.2901799 ◽

2019 ◽

Vol 7 ◽

pp. 32128-32136 ◽

Cited By ~ 1

Author(s):

Bin Wang ◽

Xinyu Fan ◽

Yuanxiu Fu ◽

Zuyuan He

Keyword(s):

Temperature Measurement ◽

Spatial Resolution ◽

Domain Analysis ◽

Measurement Range ◽

Optical Correlation ◽

Extraction Algorithm

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Turbine Blade Three-Wavelength Radiation Temperature Measurement Method Based on Reflection Error Correction

Applied Sciences ◽

10.3390/app11093913 ◽

2021 ◽

Vol 11 (9) ◽

pp. 3913

Author(s):

Kaifeng Zheng ◽

Jinguang Lü ◽

Yingze Zhao ◽

Jin Tao ◽

Yuxin Qin ◽

...

Keyword(s):

Temperature Measurement ◽

Turbine Blade ◽

Measurement Method ◽

Turbine Blades ◽

Target Surface ◽

Maximum Error ◽

Radiation Temperature ◽

Average Error ◽

Real Surface ◽

Wavelength Radiation

The turbine blade is a key component in an aeroengine. Currently, measuring the turbine blade radiation temperature always requires obtaining the emissivity of the target surface in advance. However, changes in the emissivity and the reflected ambient radiation cause large errors in measurement results. In this paper, a three-wavelength radiation temperature measurement method was developed, without known emissivity, for reflection correction. Firstly, a three-dimensional dynamic reflection model of the turbine blade was established to describe the ambient radiation of the target blade based on the real surface of the engine turbine blade. Secondly, based on the reflection correction model, a three-wavelength radiation temperature measurement algorithm, independent of surface emissivity, was proposed to improve the measurement accuracy of the turbine blade radiation temperature in the engine. Finally, an experimental platform was built to verify the temperature measurement method. Compared with three conventional colorimetric methods, this method achieved an improved performance on blade temperature measurement, demonstrating a decline in the maximum error from 6.09% to 2.13% and in the average error from 2.82% to 1.20%. The proposed method would benefit the accuracy in the high-temperature measurement of turbine blades.

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