• 제목/요약/키워드: Temperature measurement

검색결과 5,010건 처리시간 0.032초

Simultaneous Temperature and Velocity Fields Measurements near the Boiling Point

  • Doh, Deog-Hee;Hwang, Tae-Gyu;Koo, Bon-Young;Kim, Seok-Ro
    • Journal of Advanced Marine Engineering and Technology
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    • 제31권5호
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    • pp.531-542
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    • 2007
  • Simultaneous measurement technique for temperature and velocity fields near a heated solid body has been constructed. The measurement system consists of a 3-late CCD color camera, a color image grabber, a 1ighting system, a host computer and a software for the whole quantification process. Thermo Chromic Liquid Crystals (TCLC) was used as temperature sensors. A neural network was used to get a calibration curve between the temperature and the color change of the TCLC in order to enhance the dynamic range of temperature measurement. The velocity field measurement was attained by the use of the fray-level images taken for the flow field, and by introducing the cross-correlation technique. The temperature and the velocity fields of the forced and the natural convective flows neat the surface of a cartridge heater were measured simultaneously with the constructed measurement system.

엔진 고공 시험에서 연료 유량 측정용 터빈 유량계의 측정 불확도 분석 (Measurement Uncertainty Analysis of a Turbine Flowmeter for Fuel Flow Measurement in Altitude Engine Test)

  • 양인영
    • 한국유체기계학회 논문집
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    • 제14권1호
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    • pp.42-47
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    • 2011
  • Measurement uncertainty analysis of fuel flow using turbine flowmeter was performed for the case of altitude engine test. SAE ARP4990 was used as the fuel flow calculation procedure, as well as the mathematical model for the measurement uncertainty assessment. The assessment was performed using Sensitivity Coefficient Method. 11 parameters involved in the calculation of the flow rate were considered. For the given equipment setup, the measurement uncertainty of fuel flow was assessed in the range of 1.19~1.86 % for high flow rate case, and 1.47~3.31 % for low flow rate case. Fluctuation in frequency signal from the flowmeter had the largest influence on the fuel flow measurement uncertainty for most cases. Fuel temperature measurement had the largest for the case of low temperature and low flow rate. Calibration of K-factor and the interpolation of the calibration data also had large influence, especially for the case of very low temperature. Reference temperature, at which the reference viscosity of the sample fuel was measured, had relatively small contribution, but it became larger when the operating fuel temperature was far from reference temperature. Measurement of reference density had small contribution on the flow rate uncertainty. Fuel pressure and atmospheric pressure measurement had virtually no contribution on the flow rate uncertainty.

오일 냉각기용 온도센서의 동적 온도 민감도에 관한 연구 (Dynamic Temperature Sensitivity of Temperature Sensors for the Oil Coolers)

  • 이찬홍;이상호;박효찬
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2003년도 춘계학술대회 논문집
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    • pp.62-67
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    • 2003
  • In this Paper, the dynamic temperature sensitivity and mu. temperature measurement errors of oil and air sensor in oil cooler are evaluated to predict design validity of sensors under special oil and atmosphere temperature changes. The temperature tracking of oil sensors for periodic temperature changes is simulated by obtaining thermal response coefficient from experiment. By this method, it is possible to design the optimal sensors with the admitted temperature measurement errors.

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ON MEASURING THE WELDING TEMPERATURE OF CONNECTOR

  • Deng Jyh-jeng
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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    • pp.361-377
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    • 1998
  • The measurement of welding temperature of connector is usually performed with an infra red temperature gauge. However, the factors, which influence the temperature measurement, are rarely known. This research used the welding temperature measurement of the connector as an example, applying the experimental design, in two-phase experiments, to search the affecting factors. In phase-I experiment, we used a resolution III, seven-factor fractional factorial design with two levels for each factor. The result showed that none of the factor was significant in affecting the welding temperature when the type I error ${\alpha}$ was 0.05. Next, we did the phase-II factorial experiment with three factors and each factor had three levels. The experiment showed the experimental time was significant in affecting the temperature measurement when the type I error ${\alpha}$ was 0.05. Further Duncan's multiple range tests on the second experimental data showed that the later the experimental time, the weaker the light intensity could have on the temperature measurement and the average of the highest temperatures was lower. Moreover, the later the experimental time, the smaller was the variance of the temperature measurement and the difference between the averages of the highest and the lowest temperatures was also lower.

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Study on Automatic Human Body Temperature Measurement System Based on Internet of Things

  • Quoc Cuong Nguyen;Quoc Huy Nguyen;Jaesang Cha
    • International Journal of Internet, Broadcasting and Communication
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    • 제16권2호
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    • pp.50-58
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    • 2024
  • Body temperature plays an important role in medicine, some diseases are characterized by changes in human body temperature. Monitoring body temperature also allows doctors to monitor the effectiveness of medical treatments. Accurate body temperature measurement is key to detecting fevers, especially fevers related to infection with the SARS-CoV-2 virus that caused the recent Covid-19 pandemic in the world. The solution of measuring body temperature using a thermal camera is fast but has a high cost and is not suitable for some organizations with difficult economic conditions today. Use a medical thermometer to measure body temperature directly for a slow rate, making it easier to spread disease from person to person. In this paper, we propose a completely automatic body temperature measurement system that can adjust the height according to the person taking the measurement, has a measurement logging system and is monitored via the internet. Experimental results show that the proposed method has successfully created a fully automatic human body measurement system. Furthermore, this research also helps the school's scientists and students gain more knowledge and experience to apply Internet of Things technology in real life.

Measurement of local wall temperature and heat flux using the two-thermocouple method for a heat transfer tube

  • Ahn, Taehwan;Kang, Jinhoon;Jeong, Jae Jun;Yun, Byongjo
    • Nuclear Engineering and Technology
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    • 제51권7호
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    • pp.1853-1859
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    • 2019
  • The two-thermocouple method was investigated experimentally to evaluate its accuracy for the measurement of local wall temperature and heat flux on a heat transfer tube with an electric heater rod installed in an annulus channel. This work revealed that a thermocouple flush-mounted in a surface groove serves as a good reference method for the accurate measurement of the wall temperature, whereas two thermocouples installed at different depths in the tube wall yield large bias errors in the calculation of local heat flux and wall temperature. These errors result from conductive and convective changes due to the fin effect of the thermocouple sheath. To eliminate the bias errors, we proposed a calibration method based on both the local heat flux and Reynolds number of the cooling water. The calibration method was validated with the measurement of local heat flux and wall temperature against experimental data obtained for single-phase convection and two-phase condensation flows inside the tube. In the manuscript, Section 1 introduces the importance of local heat flux and wall temperature measurement, Section 2 explains the experimental setup, and Section 3 provides the measured data, causes of measurement errors, and the developed calibration method.

Analyzing the Influence of Spatial Sampling Rate on Three-dimensional Temperature-field Reconstruction

  • Shenxiang Feng;Xiaojian Hao;Tong Wei;Xiaodong Huang;Pan Pei;Chenyang Xu
    • Current Optics and Photonics
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    • 제8권3호
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    • pp.246-258
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    • 2024
  • In aerospace and energy engineering, the reconstruction of three-dimensional (3D) temperature distributions is crucial. Traditional methods like algebraic iterative reconstruction and filtered back-projection depend on voxel division for resolution. Our algorithm, blending deep learning with computer graphics rendering, converts 2D projections into light rays for uniform sampling, using a fully connected neural network to depict the 3D temperature field. Although effective in capturing internal details, it demands multiple cameras for varied angle projections, increasing cost and computational needs. We assess the impact of camera number on reconstruction accuracy and efficiency, conducting butane-flame simulations with different camera setups (6 to 18 cameras). The results show improved accuracy with more cameras, with 12 cameras achieving optimal computational efficiency (1.263) and low error rates. Verification experiments with 9, 12, and 15 cameras, using thermocouples, confirm that the 12-camera setup as the best, balancing efficiency and accuracy. This offers a feasible, cost-effective solution for real-world applications like engine testing and environmental monitoring, improving accuracy and resource management in temperature measurement.

완전평면 브라운관의 고온 변형률 측정에 관한 연구 (A Study on the High-Temperature Strain Measurement of Perfectly Flat CRT)

  • 강대진;김국원;한응교
    • 한국정밀공학회지
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    • 제16권8호
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    • pp.23-27
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    • 1999
  • The measurement of thr high-temperature strains is one of the challenging subjects in mechanical engineering. For the precise measurement, proper high-temperature strain gauge, cement and skilled technique are needed. In this paper, a high-temperature strain measurement is performed for the perfectly flat CRT. As this CRT is structurally very weak, cracking of the panel frequently occurs during the heat cycle in the furnace. From the measured strain variations of the panel with tension shadow mask, the crack behavior can be explained.

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인듐안티모나이드 포토 센서를 이용한 CRT 섀도우 마스크의 비접촉 온도 측정에 관한 연구 (A study on the non-contact measurement for the temperature of shadow mask of Cathode Ray Tube using InSb photo sensor)

  • 강대진;박정우;송창섭
    • 한국정밀공학회지
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    • 제14권3호
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    • pp.15-20
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    • 1997
  • This paper presents the experimental study of the non-contact temperature measurement for the shadow mask of cathode ray tube using InSb sensor. At present, High resolution of CRT(Cathode Ray Tube) is needed broadly; therefore, the measurement of temperature distribution of shadow mask in CRT during operation is important to analyze the thermal deformation of shadow mask. Most of the studies could not measure the temperature distribution of shadow mask precisely. We studied the temperature dis- tribution of shadow mask using InSb photo sensor for 17" cathode ray tube (CRT). Experiments using ther- mocouple are performed to validate the results of non-contact measurement. The results agree well with those results of non-contact method using InSb sensor.nsor.

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고온 접촉식 탐상용 초음파 탐촉자 개발 및 평가 (Development and Characterization of Ultrasonic transducers for High Temperature Contact Measurement)

  • 김기복;김병극;이승석;윤남원;윤동진;안윤국
    • 비파괴검사학회지
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    • 제23권1호
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    • pp.14-20
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    • 2003
  • 고온$(500^{\circ}C)$ 환경에서 접촉식 탐상이 가능한 초음파 탐촉자를 개발하고 평가하였다. 고온용 탐촉자는 Curie 온도가 $600^{\circ}C$ 이상인 bismuth titanate 계열의 압전세라믹 소자, 텅스텐 분말과 inorganic binder를 혼합한 후면재, 알루미나 튜브, 전면재, 하우징 등으로 구성되었다. 기본 공진주파수가 각각 1.04 및 2.08 MHz의 2 종류 탐촉자를 제작하였으며 각종 고온용 커플런트의 온도특성을 시험하였다. 개발된 고온용 탐촉자를 이용하여 강재 시편을 대상으로 시편에서의 초음파 반사신호를 측정한 결과 시편의 온도가 증가함에 따라 반사신호의 크기는 감소하였다. 고온에서 반복측정 실험결과 $500^{\circ}C$에서 연속적인 접촉식 초음파 탐상이 가능한 것으로 나타났다.