• Title/Summary/Keyword: Monte Carlo collision

Search Result 104, Processing Time 0.027 seconds

Ionization and Diffusion Coefficients in CH4 Gas by Simulation (시뮬레이션에 의한 CH4 기체의 전리 및 확산계수)

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.63 no.4
    • /
    • pp.317-321
    • /
    • 2014
  • This paper describes the information for quantitative simulation of weakly ionized plasma. We must grasp the meaning of the plasma state condition to utilize engineering application and to understand materials of plasma state. Using quantitative simulations of weakly ionized plasma, we can analyze gas characteristic. In this paper, the electron Ionization and diffusion Coefficients in CH4CH4 has been analysed over the E/N range 0.1~300[Td], at the 300[KK] by the two term approximation Boltzmann equation method and Monte Carlo Simulation. Boltzmann equation method has also been used to predict swarm parameter using the same cross sections as input. The behavior of electron has been calculated to give swarm parameter for the electron energy distribution function has been analysed in CH4CH4 at E/N=10, 100 for a case of the equilibrium region in the mean energy. A set of electron collision cross section has been assembled and used in Monte Carlo simulation to predict values of swarm parameters. The result of Boltzmann equation and Monte Carlo Simulation has been compared with experimental data by Ohmori, Lucas and Carter. The swarm parameter from the swarm study are expected to sever as a critical test of current theories of low energy scattering by atoms and molecules.

Modeling of 3D Monte Carlo Ion Implantation in the Ultra-Low Energy for the Fabrication of Giga-Bit Devices (기가 비트급 소자 제작을 위한 3차원 몬테카를로 극 저 에너지 이온 주입 모델링)

  • Ban, Yong-Chan;Kwon, Oh-Seob;Won, Tae-Young
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.37 no.10
    • /
    • pp.1-10
    • /
    • 2000
  • A rigorous modeling of ultra-low energy implantation is becoming increasingly more important as devices shrink to deep submicron dimensions. In this paper, we have developed an efficient three-dimensional Monte Carlo ion implantation model based on a modified Binary Collision Approximation(BCA). To this purpose, the modified electronic stopping model and the multi-body collision model have been taken into account in this simulator. The dopant and damage profiles show very good agreement with SIMS(Secondary Ion Mass Spectroscopy) data and RBS(Rutherford Backscattering Spectroscopy) data, respectively. Moreover, the ion distribution replica method has been implemented into the model to get a computational efficiency in a 3D simulation, and we have calculated the 3D Monte Carlo simulation into the topographically complex structure.

  • PDF

The simulation of electrons swarm parameter in He gas is used by Boltzman equation (볼츠만 방정식을 이용한 Helium 가스의 전자군 파라미터 시뮬레이션)

  • 송병두;하성철;김대연
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1998.11a
    • /
    • pp.155-158
    • /
    • 1998
  • This paper is calculated at electron swarm simulation by Back Prolongation of Boltzmann equation for range of E/N values from 0.1~200[Td], pressure P= 1.0[Torr], temperature T=300[ 。K], the electron swarm parameter(drift velocity, longitudinal . transverse diffusion coefficients, characteristic energy, etc) in He gas is used by electron collision cross section, particularly explicate the simulation technique, and consider electrical conduction characteristic of He gas.

  • PDF

Effect of Pore Geometry on Gas Adsorption: Grand Canonical Monte Carlo Simulation Studies

  • Lee, Eon-Ji;Chang, Rak-Woo;Han, Ji-Hyung;Chung, Taek-Dong
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.3
    • /
    • pp.901-905
    • /
    • 2012
  • In this study, we investigated the pure geometrical effect of porous materials in gas adsorption using the grand canonical Monte Carlo simulations of primitive gas-pore models with various pore geometries such as planar, cylindrical, and random pore geometries. Although the model does not possess atomistic level details of porous materials, our simulation results provided many insightful information in the effect of pore geometry on the adsorption behavior of gas molecules. First, the surface curvature of porous materials plays a significant role in the amount of adsorbed gas molecules: the concave surface such as in cylindrical pores induces more attraction between gas molecules and pore, which results in the enhanced gas adsorption. On the contrary, the convex surface of random pores gives the opposite effect. Second, this geometrical effect shows a nonmonotonic dependence on the gas-pore interaction strength and length. Third, as the external gas pressure is increased, the change in the gas adsorption due to pore geometry is reduced. Finally, the pore geometry also affects the collision dynamics of gas molecules. Since our model is based on primitive description of fluid molecules, our conclusion can be applied to any fluidic systems including reactant-electrode systems.

Ionization and Attachment Coefficients in CF4, CH4, Ar Mixtures Gas (CF4, CH4, Ar 혼합기체의 전리와 부착계수)

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.61 no.1
    • /
    • pp.13-17
    • /
    • 2012
  • Ionization and Attachment Coefficients in pure CH4CH4, CF4CF4 and mixtures of CF4CF4 and Ar, have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-term approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The calculations of electron swarm parameters require the knowledge of several collision cross-sections of electron beam. Thus, published momentum transfer, ionization, vibration, attachment, electronic excitation, and dissociation cross-sections of electrons for CH4CH4, CF4CF4 and Ar, were used. The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in CF4CF4-Ar mixtures shows the Maxwellian distribution for energy. That is, f(εε) has the symmetrical shape whose axis of symmetry is a most probably energy. The proposed theoretical simulation techniques in this work will be useful to predict the fundamental process of charged particles and the breakdown properties of gas mixtures.

New Monte-Carlo based simulation program suitable for low-energy ions irradiation in pure materials

  • Ghadeer H. Al-Malkawi;Al-Montaser Bellah A. Al-Ajlony;Khaled F. Al-Shboul;Ahmed Hassanein
    • Nuclear Engineering and Technology
    • /
    • v.55 no.4
    • /
    • pp.1287-1299
    • /
    • 2023
  • A new Monte-Carlo-based computer program (RDS-BASIC) is developed to simulate the transport of energetic ions in pure matter. This computer program is utilizing an algorithm that uses detailed numerical solutions for the classical scattering integral for evaluating the outcomes of the binary collision processes. This approach is adopted by several prominent similar simulation programs and is known to provide results with higher accuracy compared to other approaches that use approximations to shorten the simulation time. Furthermore, RDS-BASIC simulation program contains special methods to reduce the displacement energy threshold of surface atoms. This implementation is found essential for accurate simulation results for sputtering yield in the case of very low energy ions irradiation (near sputtering energy threshold) and also successfully solve the problem of simultaneously obtaining an acceptable number of atomic displacements per incident ions. Results of our simulation for several irradiation systems are presented and compared with their respective TRIM (SRIM-2013) and the state-of-the-art SDTrimSP simulation results. Our sputtering simulation results were also compared with available experimental data. The simulation execution time for these different simulation programs has also been compared.

Comparative analysis among deterministic and stochastic collision damage models for oil tanker and bulk carrier reliability

  • Campanile, A.;Piscopo, V.;Scamardella, A.
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.10 no.1
    • /
    • pp.21-36
    • /
    • 2018
  • The incidence of collision damage models on oil tanker and bulk carrier reliability is investigated considering the IACS deterministic model against GOALDS/IMO database statistics for collision events, substantiating the probabilistic model. Statistical properties of hull girder residual strength are determined by Monte Carlo simulation, based on random generation of damage dimensions and a modified form of incremental-iterative method, to account for neutral axis rotation and equilibrium of horizontal bending moment, due to cross-section asymmetry after collision events. Reliability analysis is performed, to investigate the incidence of collision penetration depth and height statistical properties on hull girder sagging/hogging failure probabilities. Besides, the incidence of corrosion on hull girder residual strength and reliability is also discussed, focussing on gross, hull girder net and local net scantlings, respectively. The ISSC double hull oil tanker and single side bulk carrier, assumed as test cases in the ISSC 2012 report, are taken as reference ships.

Particle swarm optimization-based receding horizon formation control of multi-agent surface vehicles

  • Kim, Donghoon;Lee, Seung-Mok;Jung, Sungwook;Koo, Jungmo;Myung, Hyun
    • Advances in robotics research
    • /
    • v.2 no.2
    • /
    • pp.161-182
    • /
    • 2018
  • This paper proposes a novel receding horizon control (RHC) algorithm for formation control of a swarm of unmanned surface vehicles (USVs) using particle swarm optimization (PSO). The proposed control algorithm provides the coordinated path tracking of multi-agent USVs while preventing collisions and considering external disturbances such as ocean currents. A three degrees-of-freedom kinematic model of the USV is used for the RHC with guaranteed stability and convergence by incorporating a sequential Monte Carlo (SMC)-based particle initialization. An ocean current model-based estimator is designed to compensate for the effect of ocean currents on the USVs. This method is compared with the PSO-based RHC algorithms to demonstrate the performance of the formation control and the collision avoidance in the presence of ocean currents through numerical simulations.

Mean energy of electrons in SF6SF6-Ar Mixtures Gas (SF6SF6-Ar 혼합기체(混合氣體)의 전자(電子) 평균(平均)에너지)

  • Kim, Sang-Nam;Seong, Nak-Jin
    • Proceedings of the KIEE Conference
    • /
    • 2003.07e
    • /
    • pp.75-78
    • /
    • 2003
  • Energy distribution function for electrons in SF6SF6-Ar mixtures gas used by MCS-BEq algorithm has been analysed over the E/N range 3030030300[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[%] SF6SF6-Ar mixtures were measured by time-of-flight(TOF) method. 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. The transport coefficients for electrons in (0.2[%])SF6SF6-Ar and (0.5[%]SF6SF6 - Ar mixtures were measured by time-of-flight method, and the electron energy distribution function and the parameters of the velocity and the diffusion were determined by the variation of the collision cross-sections with energy. The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

  • PDF

Analysis on the Mean energy of electrons in SF6ArSF6Ar Mixtures Gas used by MCS-BEq Algorithm (SF6ArSF6Ar 혼합기체(混合氣體)의 MCS-BEq알고리즘에 의한 전자(電子) 평균(平均)에너지 해석(解析))

  • Kim, Sang-Nam;Ha, Sung-Chul
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2004.05a
    • /
    • pp.281-284
    • /
    • 2004
  • Mean energy of electrons in SF6ArSF6Ar Mixtures Gas used by MCS-BEq algorithm has been analysed over the E/N range 30300[Td]30300[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[%] SF6ArSF6Ar, 0.1[%] and 5.0[%], SF6ArSF6Ar mixtures were measured by time-of-flight(TOF) method. The transport Coefficients for electrons in (100[%])SF6SF6. (100[%])Ar, (0.2[%])SF6ArSF6Ar and (0.5[%]) SF6ArSF6Ar, (5.0[%]) SF6ArSF6Ar, (0.1[%])SF6ArSF6Ar mixtures were measured by time-of-flight method, and the electron energy distribution function and the parameters of the velocity and the diffusion were determined by the variation of the collision cross-sections with energy. The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

  • PDF