• 제목/요약/키워드: thermal characterization

검색결과 1,151건 처리시간 0.037초

고집광 태양열 시뮬레이터의 광학 특성 평가 (Optical Characterization of a High-Flux Solar Thermal Simulator)

  • 채관교;이현진;윤환기;김종규;강용혁;이성욱
    • 한국태양에너지학회 논문집
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    • 제35권3호
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    • pp.65-71
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    • 2015
  • A solar thermal simulator is suitable for indoor experiments of solar receivers and reactors when solar insolation and weather conditions are not favorable. Moreover, due to the easy control of electric power input, the solar thermal simulator allows the adjustment of power input incident on solar receivers and reactors and thus the implementation of accurate experiments. We manufactured a solar simulator, which is comprised of three sets of a xenon lamp and an elliptical reflector. In order to serve as a test facility, optical characterization of the solar simulator via radiation heat flux measurement is a critical prerequisite. We applied the flux mapping method to measuring the heat flux distribution of the three lamps. We presented the measurement results in terms of the heat flux distribution, the peak heat flux, the power distribution, the maximum power, and the efficiency for electric power conversion into radiation power. Characterization results show that our solar simulator provides the peak heat flux of $3,019kW/m^2$, the maximum power of 16.9 kW, and the conversion efficiency of 45%, additionally with a 10% operation margin for output increase.

Fabrication and Characterization of Thermally Actuated Bimorph Probe for Living Cell Measurements with Experimental and Numerical Analysis

  • Cho Young-Hak;Kang Beom-Joon;Hong Seok-Kwan;Kang Jeong-Jin
    • Journal of Mechanical Science and Technology
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    • 제20권3호
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    • pp.297-309
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    • 2006
  • This paper deals with a novel structure for single-cell characterization which makes use of bimorph micro thermal actuators combined with electrical sensor device and integrated microfluidic channel. The goal for this device is to capture and characterize individual biocell. Quantitative and qualitative characteristics of bimorph thermal actuator were analyzed with finite element analysis methods. Furthermore, optimization for the dimension of cantilevers and integrated parallel probe systems with microfluidic channels is able to be realized through the virtual simulation for actuation and the practical fabrication of prototype of probes. The experimental value of probe deflection was in accordance with the simulated one.

Characterization of Boron Nanoparticles Synthesized with a Thermal Plasma System

  • Shin, Weon-Gyu;Girshick, Steven L.;Oh, Dong-Ho
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.369-369
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    • 2011
  • In the current work, we demonstrate the gas phase plasma synthesis of ultrafine boron nanoparticles by decomposing boron trichloride (BCl3) gas in an argon-hydrogen thermal plasma and quenching the hot plasma by expansion through a ceramic nozzle, driving the homogeneous nucleation of nanoparticles. It is shown that ultrafine nanoparticles can be produced from the experiments. We also show the characterization results regarding the oxidation of boron nanoparticles at room temperature using X-ray Photoelectron Spectroscopy (XPS) and the combined Scanning Transmission Electron Microscope (STEM) and Electron Energy Loss Spectroscopy (EELS).

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대두유 에스테르계 절연유의 합성과 분석 (Study on the synthesis and characterization of soybean based transformer oils)

  • 한동희;조한구;한세원;안명상;오대희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.244-245
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    • 2005
  • Electrical insulation is one of the most important parts in a high voltage apparatus. Traditionally mineral oils and synthetic esters have been widely used as dielectric coolants for power transformers. Recently, researchers are interested in the environmental friendly vegetable oil from environmental viewpoint. This paper reports on the synthesis and characterization of soybean based ester oils. Two different types of soybean based transformer oils, named as methyl ester and isopropyl ester were synthesized. The synthesis of these esters was achieved by transesterification reactions of soybean oil and alcohol in the presence of catalyst. The GC and NMR spectroscopic analysis of the esters have been performed. The thermal stability of the esters was determined by thermal gravimetric analysis(TGA).

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TPS를 통한 열물성치 획득 및 네트워크모델을 이용한 열해석 (Measurement of thermal properties by TPS-technique and thermal network analysis)

  • 윤태섭;김영진
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.263-268
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    • 2010
  • Thermal characterization of geomaterials has significant implication on the geothermal energy, disposal of nuclear wastes, geological sequestration of carbon dioxides and recovery of hydrocarbon resources. Heat transfer in multiphase materials is dominated by the thermal conductivity of consisting components, porosity, degree of saturation and overburden pressure, which have been investigated by the empirical correlation at macro-scale. The thermal measurement by Transient Plane Source (TPS) and associated algorithm for interpretation of thermal behavior in geomaterials corroborate the robustness of sensing techniques. The method simultaneously provides thermal conductivity, diffusivity and volumetric heat capacity. The newly introduced thermal network model enables estimating thermal conductivity of geomaterials subjected to the effective stress, which has not been evaluated using previous thermal models. The proposed methods shows the applicability of reliability of TPS technique and thermal network model.

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