• 제목/요약/키워드: The Boltzmann equation

검색결과 219건 처리시간 0.023초

시뮬레이션에 의한 $CF_4$ 기체의 전자수송특성 (A Study of the Insulation Characteristic in $CF_4$ Gas)

  • 김상남;황청호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.468-469
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    • 2007
  • In this paper, the electron transport characteristics in $CF_4$ has been analysed over the E/N range 1~300[Td] by a two-tenn approximation Boltzmann equation method and by a Monte Carlo simulation. The motion has been calculated to give swarm parameters for the electron drift velocity, longitudinal diffusion coefficient, the ratio of the diffusion coefficient to the mobility, electron ionization and attachment coefficients, effective ionization coefficient, mean energy, collision frequency and the electron energy distribution function. The swarm parameter from the swarm study are expected to serve as a critical test of current theories of low energy electron scattering by atoms and molecules, in particular, as well as crucial information for quantitative simulations of weakly ionized plasmas.

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MCS-BEq 알고리즘에 의한 $SiH_4$ 기체의 전자수송특성 (Characteristics of Electron Transport in $SiH_4$ Gas used by MCS-BEq Algorithm)

  • 김상남;성낙진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 학술대회 논문집 전문대학교육위원
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    • pp.159-162
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    • 2006
  • In this paper energy distribution function in $SiH_4$ has been analysed over the E/N range 0.5${\sim}$300Td and Pressure value 0.5, 1.0, 2.5 Torr by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The motion has been calculated to give swarm parameters for the electron drift velocity, diffusion coefficient, electron ionization, mean energy and the electron energy distribution function. The electron energy distribution function has been analysed in $SiH_4$ at E/N=30, 50Td for a case of the equilibrium region in the mean electron energy and respective set of electron collision cross sections. The results show that the deduced electron drift velocities, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values.

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MCS-BEq에 의한 $SF_6$-He 혼합기체의 에너지 분포함수 (Energy Distribution Function for Electrons in $SF_6$+He mixtures gas used by MCS-BEq)

  • 성낙진;김상남
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
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    • pp.41-44
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    • 2004
  • This paper describes the electron transport characteristics in $SF_6$-He gas calculated for range of E/N values from 50${\sim}$700[Td] by the Monte Carlo simulation(MCS) and Boltzmann equation(BEq) method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters are obtained by TOF method. The results gained that the values of the electron swarm parameters such as the electron drift velocity. the electron ionization or attachment coefficients. longitudinal and transverse diffusion coefficients agree with the experimental and theoretical for a range of E/N.

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$CF_4$ 기체의 MCS-BEq 알고리즘에 의한 전자에너지 분포함수 (Electron Energy Distribution Function in $CF_4$ Gas used by MCS-BE Algorithm)

  • 박재세;김상남;김일남
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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    • pp.102-105
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    • 2002
  • In this paper, the electron transport characteristics in $CF_4$ has been analysed over the E/N range 1${\sim}$300 [Td] by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The motion has been calculated to give swarm parameters for the electron drift velocity, longitudinal diffusion coefficient, the ratio of the diffusion coefficient to the mobility, electron ionization and attachment coefficients, effective ionization coefficient, mean energy, collision frequency and the electron energy distribution function. The swarm parameter from the swarm study are expected to serve as a critical test of current theories of low energy electron scattering by atoms and molecules, in particular, as well as crucial information for quantitative simulations of weakly ionized plasmas.

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SF6-Ar 혼합기체의 전자분포함수와 이동속도 (Distribution Function and Drift Velocities in Mixtures of SF6 and Ar)

  • 김상남
    • 전기학회논문지P
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    • 제59권2호
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    • pp.146-150
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    • 2010
  • Distribution Function and Drift velocities for electrons in $SF_6$-Ar mixtures gases used by MCS-BEq algorithm has been analysed over the E/N range 30~300[Td] by a two term Boltzmann equation and by a Monte Carlo simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6$-Ar mixtures were measured by time-of-flight method. The results obtained in this work will provide valuable information on the fundamental behaviors of electrons in weakly ionized gases and the role of electron attachment in the choice of better gases and unitary gas dielectrics or electro negative components in dielectric gas mixtures. The results show that the deduced electron drift velocities agree reasonably well with theoretical for a rang of E/N values.

MCS-BE에 의한 $SF_6$+He 혼합기체의 전자수송특성 해석 (Analysis of electron transport properties in $SF_6$+He mixture gas used by MCS-BE)

  • 하설철;송병두;유회영;김상남;백승권
    • 한국전기전자재료학회논문지
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    • 제13권4호
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    • pp.359-364
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    • 2000
  • The paper describes the electron transport characteristics in SP$_{6}$+He gas calculated E/N values 0.1~700[Td] by the Monte Carlos simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters obtained by TOF method. This study gained the values of the electron swarm parameters such as the electron drift velocity the electron ionization or attachment coefficients longitudinal and transverse diffusion coefficients for SF$_{6}$+He gas at a range of E/N.E/N.

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$GeH_4$기체의 전자수송계수에 관한 연구 (A study on the electron transport coefficients in $GeH_4$ gas)

  • 류선미;전병훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1404_1405
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    • 2009
  • For quantitative understanding of gas discharge phenomena, we should know electron collision cross section. $GeH_4$ is used in many applications with $Si_2H_6$ gas, such as amorphous alloy, a thin film of silicon and solar cell. Therefore, we understand the electron transport characteristics and analysed the electron transport coefficients, the electron drift velocity W, the longitudinal and transverse diffusion coefficient $ND_L$ and $ND_T$, and the ionization coefficient $\alpha$/N in $GeH_4$gas over the E/N range from 0.01 to 1000 Td by two-term approximation of the Boltzmann equation.

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TOF법에 의한 $CF_4+Ar$ 혼합기체의 전자수송특성 해석 (Analysis of electron transport properties of $CF_4+Ar$ mixtures gas by the TOF method)

  • 서상현;하성철;유회영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.279-283
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    • 1998
  • The electron swarm parameters in the$CF_4$(O.l%, 5%)+Ar mixtures are measured by time of flight method over the E/N(Td) range from 10 to 300LTdl. A two-term approximation of the Boltzmann equation analysis and Monte Carlo simulation have been also used to study electron transport coefficients. We have calculated W, NDL, NDT, $\alpha$ and the limiting breakdown electric field to gas mixtures ratio in pure $CF_4$ gas and$CF_4+Ar$ mixtures. The measured results and the calculated results have been compared each other paper.

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복사 장치를 이용한 온도와 형상계수의 변화에 따른 방사율에 관한 실험적 연구 (Experimental Study of Emissivity with the Variation of Temperature and Shape Factor Using the Radiation Apparatus)

  • 김청래;정병철;강형석
    • 산업기술연구
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    • 제25권B호
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    • pp.135-140
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    • 2005
  • Voltage of radiometer is measured experimentally using the radiation apparatus in each case of iron- and copper-plates as specimen heating device. The length between radiometer and conical shield and the temperature of specimen heating device are considered as variables. The length between radiometer and conical shield controls the amount of radiation from the specimen heating device. Emissivity for both iron-and copper-plates are calculated by using Stefan-Boltzmann equation. One of results shows that emissivity for both materials increases as the length between radiometer and conical shield increases.

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화학반응을 수반하는 극초음속 희박류 유동의 직접모사법 개발 (A DSMC Technique for the Analysis of Chemical Reactions in Hypersonic Rarefied Flows)

  • 정찬홍;윤성준
    • 한국전산유체공학회지
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    • 제4권3호
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    • pp.63-70
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    • 1999
  • A Direct simulation Monte-Carlo (DSMC) code is developed, which employs the Monte-Carlo statistical sampling technique to investigate hypersonic rarefied gas flows accompanying chemical reactions. The DSMC method is a numerical simulation technique for analyzing the Boltzmann equation by modeling a real gas flow using a representative set of molecules. Due to the limitations in computational requirements. the present method is applied to a flow around a simple two-dimensional object in exit velocity of 7.6 km/sec at an altitude of 90 km. For the calculation of chemical reactions an air model with five species (O₂, N₂, O, N, NO) and 19 chemical reactions is employed. The simulated result showed various rarefaction effects in the hypersonic flow with chemical reactions.

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