• Title/Summary/Keyword: 볼츠만 분포

Search Result 25, Processing Time 0.02 seconds

Analysis of Electron Swarm Transport Coefficients by Collision Cross Section in Na-He Gas Mixtures (Na-He 혼합증기중에서 충돌단면적에 의한 전자군의 수송계수 해석)

  • 하성철;백수현
    • Electrical & Electronic Materials
    • /
    • v.3 no.2
    • /
    • pp.138-146
    • /
    • 1990
  • 볼츠만 수송방정식에 관한 홀스타인의 식을 사용하여 온도는 273.deg.K, 상대전계의 세기가 1.leq.E/P..leq.30(V/cm Torr)인 때의 Na와 He 단일기체중을 통과하는 전자의 에너지분포함수와 수송계수를 계산하였다. 그리고 전자 이동속도의 결과치를 실험값과 비교하였으며 실험치와 계산치가 일치하도록 충돌단면적을 수정하여 계산에 적용하였다. 이러한 방법으로 Hesms 0.1[eV]-50[eV]까지 Na는 0.1[eV]-5[eV]까지의 에너지범위에서 결정된 운동량변환단면적의 값은 제한된 범위에서 Crompton 및 Nakamura의 값과 거의 일치하였다. 또한 이와 같이하여 계산된 Na와 He 단일기체의 충돌단면적을 이용하여 온도는 273.degK, 상대전계의 세기는 1.leq.E/P$_{o}$ .leq.30(V/cm Torr)의 범위에서 Na-He 혼합증기의 혼합비율을 He:Na는 99.5:0.5, 99:1, 9:1. 1:1로 변화시켜 특성에너지, 평균에너지, 전자이동속도, 전자에너지 분포함수를 게산하였다.

  • PDF

A study on the determination of collision cross sections and the drift velocity of electron swarm in $H_2$,Co gas ($H_2$, CO 기체중에서 전자군의 이동속도 및 충돌단면적 결정에 관한 연구)

  • 하성철;하영선
    • Electrical & Electronic Materials
    • /
    • v.4 no.2
    • /
    • pp.143-149
    • /
    • 1991
  • 전계가 인가된 H$_{2}$와 CO기체중을 통과하는 전자의 탄성과 비탄성 충돌 단면적을 볼츠만방정식을 이용하여 추정하였는데 충돌 단면적은 운동량변환, 진동여기, 해리, 전자 여기 및 전리 충돌 단면적을 이동속도의 측정값 및 계산값을 비교하므로써 결정하였다. Gibson과 Phelps가 각각 계산한 H$_{2}$ 및 CO의 운동량변환 충돌단면적을 본 연구의 결과와 비교하였으며 이를 기초로하여 온도는 293.deg.K, 상대전계의 세기 E/N은 1*$10^{-17}$ [V$cm^{2}$].leq.E/N.leq.200*10 $^{17}$ [V$cm^{2}$]의 범위에서 전자에너지 분포함수를 산출하였으며 이렇게 산출된 에너지 분포함수 및 충돌단면적은 실험적으로 측정한 모든 수송계수의 값들을 만족하였다.

  • PDF

Feasibility Study on the Two-dimensional Free Surface Simulation Using the Lattice-Boltzmann Method (Lattice Boltzmann Method를 이용한 2차원 자유수면 시뮬레이션 기법연구)

  • Jung, Rho-Taek
    • Journal of the Korean Society for Marine Environment & Energy
    • /
    • v.15 no.4
    • /
    • pp.273-280
    • /
    • 2012
  • The numerical simulation using the Lattice Boltzmann Method in the field of computational fluid dynamics becomes wider in the engineering applications because of its simplicity of update rules compared to the conventional Navier-Stokes solvers. Here, a two-dimensional D2Q9 LB model is numerically tested with a few new computational treatment on the free surface. The single relaxation time is applied under the gravitational field where applied only in the higher density fluid because of its big density difference. At the free surface, the reconstruction techniques in combination with boundary conditions is adopted in order to get some distribution function coming into the fluid site from the air one, and surface tension, early stable test for the gravitional field is considered in it. With the implementation of the gravitational profile, conserving the overall mass and grid dependency are observed during the calculations and freesurface advance track is well captured with an experiment.

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

  • 서상현;하성철;유희영;김상남;송병두
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1998.11a
    • /
    • pp.159-162
    • /
    • 1998
  • This paper describes the electron transport characteristics in $SF_6$+He gas calculated for range of E/N values from 50~700[Td] by the Monte Carlo simulation and Boltzrnann equation method using a set of electmn collision cross sections determined by the authors and the values of electron swarm parameters are obtained by M F method. The results gained that the values of the electron swarm parameters such as the electron drift velocity, the electron ionization or attachment coefficents, longitudinal and h-ansverse diffusion coefficients agree with the experimental and theoretical for a range of E/N.

  • PDF

Study on the electron transport properties in $SF_6$+He mixtures gas used by MCS-BE ($SF_6$+He 혼합기체의 MCS-BE에 의한 전자수송계수 연구)

  • Kim, Sang-Nam;Seo, Sang-Hyeon;Ha, Sung-Chul;Yu, Heoi-Young;Song, Byung-Doo
    • Proceedings of the KIEE Conference
    • /
    • 1999.11a
    • /
    • pp.16-19
    • /
    • 1999
  • 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 and Boltzmann equation 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.

  • PDF

A Numerical Study of Heat transfer and Flow Analysis for a Micro-channel in The Slip Flow Regime (Slip flow 영역에서의 미소채널 내 열전달 및 유동에 관한 수치적 연구)

  • Jeong, Soo-In;Kim, Kui-Soon;Kang, Boem-Soo
    • 유체기계공업학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.391-394
    • /
    • 2006
  • In this paper, the thermal lattice Boltzmann method(TLBM) proposed by Guo et al.(2002) is applied to analyze the forced convective flow and heat transfer of 2-D micro channel. Nonequilibrium extrapolation boundary condition is adopted to simulate the velocity and temperature behavior at wall boundaries. Numerical results obtained by the present study give a good prediction of the micro fluidic characteristics with thermal effects.

  • PDF

Analysis of electron transport coefficients in Air (Air에서의 전자수송계수 특성파악)

  • Seo, Sang-Hyun;Ha, Sung-Chul;Jun, Byung-Hun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.05c
    • /
    • pp.181-184
    • /
    • 2002
  • The electron transport coefficients in Air is analysed in range of E/N values from 100~1000(Td) by a MCS and BE method. This paper have calculated W, $ND_L$,$ ND_T$, Mean energy mixtures by $N_2+O_2$. The results gained that the values of the electron swarm parameters such as the electron drift velocity, longitudinal and transverse diffusion coefficients.

  • PDF

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

  • 하설철;송병두;유회영;김상남;백승권
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.13 no.4
    • /
    • pp.359-364
    • /
    • 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.

  • PDF

Analysis of electron transport properties in $SF_6+N_2$ mixtures gas used by MCS-BE (MCS-BE에 의한 $SF_6+N_2$ 혼합기체의 전자수송특성 해석)

  • 서상현;하성철
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1999.05a
    • /
    • pp.696-699
    • /
    • 1999
  • The electron transport coefficients in $SF_6+N_2$ gas is analysed in range of E/N values from 100~900(Td) by a Monte Carlo simulation and Boltzmann method, using a set of electron collision cross sections determined by the authors. The result of the Monte Carlo simulation such as electron drift velocity, ionization and electron attachment coefficients, longitudinal and transverse diffusion coefficients in nearly agreement with the respective experimental and theoretical for a range of E/N.

  • PDF

The study of insulation-characteristic in a mixture gas includes $SF_6$ ($SF_6$를 포함하는 혼합가스의 절연특성에 관한 연구)

  • 박명진;김대연;전병훈;하성철
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1999.11a
    • /
    • pp.165-168
    • /
    • 1999
  • The electron transport coefficients in mixture gas includes SF/sub 6/ is analysed in range of E/N values from 60∼800(Td) by the Boltzmann method that using a set of electron collision crass sections determined by the researchers. Swarm parameters in the Boltzmann method simulation such as electron drift velocity, ionization and electron attachment coefficients is in nearly agreement with the respective experimental and theoretical for a range of E/N.

  • PDF