• 제목/요약/키워드: thermoelectric effects

검색결과 93건 처리시간 0.031초

Thermoelectric properties of La(1-x)MxCoO3(M=Sr, Ca;x=0, 0.1) ceramics for thermal sensors

  • 강민규;조광한;강종윤;김진상;김상식;윤석진
    • 센서학회지
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    • 제18권3호
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    • pp.234-238
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    • 2009
  • We have investigated the effects of dopant on the thermoelectric properties that $La_{(1-x)}M_xCoO_3$(M=Sr, Ca;x=0, 0.1) bulk ceramics fabricated by the conventional solid state reaction method. The Seebeck coefficient of $La_{(1-x)}M_xCoO_3$(M=Sr, Ca;x=0, 0.1) bulk ceramics was measured at wide temperature range from 300 K to 673 K. The thermoelectric properties(Seebeck coefficient and electrical resistivity) depend strongly on the kinds of dopants. Sr and Ca dopant decrease the Seebeck coefficient. Density of sintered $La_{0.9}Sr_{0.1}CoO_3$ ceramic at 1523 K was 7.12 $g/cm^2$ and Seebeck coefficient was 35 ${\mu}V/K$ at 663 K. However, the electrical resistivity of the Sr doped sample was low and stable.

$Sn_zCo_{3.7}Ni_{0.3}Sb_{12}$의 열전특성 (Thermoelectric Properties of $Sn_zCo_{3.7}Ni_{0.3}Sb_{12}$)

  • 정재용;권영송;이정일;어순철;김일호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 추계학술대회 논문집
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    • pp.83-84
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    • 2007
  • Sn-filled and Ni-doped $CoSb_3$ skutterudites were prepared by encapsulated induction melting, and their filling and doping effects on thermoelectric properties were investigated. Single phase ${\delta}-CoSb_3$ was successfully obtained by encapsulated induction melting and subsequent heat treatment at 823K for 5 days. Nickel atoms acted as electron donors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by Sn filling and Ni doping.

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고파워 전자소자에 부착된 열전생성기에 대한 pellet의 기학학적 구조가 미치는 영향 (Pellet Geometric Effects on a Thermoelectric Generator with a High Power Electronic Component)

  • 김경준
    • 동력기계공학회지
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    • 제16권2호
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    • pp.36-42
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    • 2012
  • 본 논문은 고파워 전자소자로부터 에너지를 수확하는 열전생성기의 성능에 pellet의 기학학적 구조가 미치는 영향들을 보고한다. 열경계저항을 포함하는 열전모델을 적용하여, 다양한 경계조건들과 열원의 열율들에 대해 pellet의 높이, pellet의 단면적, thermocouple의 수를 최적화 하고, 이처럼 최적화된 pellet의 기하학적 구조를 갖는 열전생성기의 성능과 일반적인 pellet으로 구성된 열전생성기의 전력생성성능과 효율이 예측되고 비교되어진다. 예측된 결과는 최적화된 pellet으로 구성된 열전생성기가 일반적인 pellet으로 구성된 열전생성기보다 2-10배까지 생성효율이 우수함을 보여준다. 최적화된 pellet으로 구성된 열전생성기와 일반적인 pellet으로 구성된 열전생성기의 열적성능도 예측되고 비교된다.

An accurate analytical exploration for dynamic response of thermo-electric CNTRC beams under driving harmonic and constant loads resting on Pasternak foundation

  • Mohammadreza Eghbali;Seyed Amirhosein Hosseini
    • Advances in nano research
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    • 제16권6호
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    • pp.549-564
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    • 2024
  • This paper aims to analyze the dynamic response of thermoelectric carbon nanotube-reinforced composite (CNTRC) beams under moving harmonic load resting on Pasternak elastic foundation. The governing equations of thermoelectric CNTRC beam are obtained based on the Karama shear deformation beam theory. The beams are resting on the Pasternak foundation. Previous articles have not performed the moving load mode with the analytical method. The exact solution for the transverse and axial dynamic response is presented using the Laplace transform. A comparison of previous studies has been published, where a good agreement is observed. Finally, some examples were used to analyze, such as excitation frequency, voltage, temperature, spring constant factors, the volume fraction of Carbon nanotubes (CNTs), the velocity of a moving harmonic load, and their influence on axial and transverse dynamic and maximum deflections. The advantages of the proposed method compared to other numerical methods are zero reduction of the error percentage that exists in numerical methods.

Al 치환이 BiCuOSe의 열전 특성에 미치는 영향 (The Effects of Al-substitution on Thermoelectric and Charge Transport Properties of BiCuOSe Compounds)

  • 안태호;임영수;서원선;박철희;박찬
    • 한국전기전자재료학회논문지
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    • 제28권12호
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    • pp.847-851
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    • 2015
  • The effects of Al-substitution on thermoelectric and charge transport properties of BiCuOSe compounds were investigated. The compounds were prepared by a solid-state reaction and consolidated by SPS (spark plasma sintering). In spite of the increase in the hole concentration with increasing Al amounts in BiCuOSe compound, the electrical conductivity at room temperature was kept constant due to the reduction of mobility. However, electrical conductivities of Al-substituted BiCuOSe compounds at elevated temperature (> 600 K) were higher than those of BiCuOSe, and this result was discussed in terms of it's the band gap energy. The Seebeck coefficient was drastically reduced when Al was substituted in Bi site, which indicated that the electronic structure was influenced by the Al-substitution into Bi-site.

Thermoelectric Seebeck and Peltier effects of single walled carbon nanotube quantum dot nanodevice

  • El-Demsisy, H.A.;Asham, M.D.;Louis, D.S.;Phillips, A.H.
    • Carbon letters
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    • 제21권
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    • pp.8-15
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    • 2017
  • The thermoelectric Seebeck and Peltier effects of a single walled carbon nanotube (SWCNT) quantum dot nanodevice are investigated, taking into consideration a certain value of applied tensile strain and induced ac-field with frequency in the terahertz (THz) range. This device is modeled as a SWCNT quantum dot connected to metallic leads. These two metallic leads operate as a source and a drain. In this three-terminal device, the conducting substance is the gate electrode. Another metallic gate is used to govern the electrostatics and the switching of the carbon nanotube channel. The substances at the carbon nanotube quantum dot/metal contact are controlled by the back gate. Results show that both the Seebeck and Peltier coefficients have random oscillation as a function of gate voltage in the Coulomb blockade regime for all types of SWCNT quantum dots. Also, the values of both the Seebeck and Peltier coefficients are enhanced, mainly due to the induced tensile strain. Results show that the three types of SWCNT quantum dot are good thermoelectric nanodevices for energy harvesting (Seebeck effect) and good coolers for nanoelectronic devices (Peltier effect).

N형 $Bi_2Te_{2.4}Se_{0.6}$ 박막의 열전 특성에 미치는 두께 및 열처리 효과 (Thickness and Annealing Effects on the Thermoelectric Properties of N-type $Bi_2Te_{2.4}Se_{0.6}$ Thin Films)

  • 김일호;장경욱
    • 한국진공학회지
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    • 제14권3호
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    • pp.153-158
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    • 2005
  • 순간 증착법으로 제조한 n형 $Bi_2Te_{2.4}Se_{0.6}$ 박막에 대하여 유효 평균 자유 행로 모델을 적용하여 박막의 두께가 열전 특성에 영향을 미치지 않는 임계 두께를 구하였다. 또한 열처리 전후 전자 농도 및 이동도의 변화를 조사하여 열처리에 의한 열전 특성의 변화를 역구조 결함과 관련하여 설명하였다. Seebeck 계수와 전기 비저항 모두 두레의 역수와 직선적인 관계를 보였으며, 이로부터 구한 평균 자유 행로는 $5120\AA$이었다. 열처리에 의해 전자의 이동도가 증가하였지만, 역구조 결함의 감소로 인해 운반자의 전자 농도가 현저히 감소하여, 결국 전기전도도가 감소하고 Seebeck 계수가 증가하였다 473k에서 1시간 동안 열처리한 Seebeck 계수와 전기전도도는 각각 $-200\;\mu V/k$$510\omega^{-1}cm^{-1}$이었다 또한, 열처리에 의해 열전 성능 인자가 상당히 향상되어 $20\times10^{-4}\;W/(mK^2)$를 나타내었다.

열전모듈 제습기의 에너지 효율과 성능에 미치는 설계 인자의 영향 분석 (The Analysis of the Effects of Design Parameters on the Energy Efficiency and Performance of TEM Dehumidifiers)

  • 이태희
    • 한국지열·수열에너지학회논문집
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    • 제16권3호
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    • pp.1-7
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    • 2020
  • To provide a design direction for high efficiency thermoelectric module(TEM) dehumidifiers, the effects of design factors of TEM dehumidifiers on dehumidification energy efficiency and performance were numerically investigated. The design factors considered in this study are the TEM capacity, the performance of heat exchangers on the heating and cooling surfaces of the TEM. The higher capacity of the TEM results the higher dehumidification energy efficiency and performance at some operating voltage. The enhanced performance of the heat exchanger on heating surface increased the dehumidification energy efficiency and performance at all the operating voltage. The enhanced performance of the heat exchanger on cooling surface decreased the dehumidification energy efficiency and performance at all operating voltage.