Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)最新文献

{"title":"Portable Parallel Code For Plasma Simulations: Development Experience And Initial Results","authors":"P. Liewer, J. Brackbill, S.R. Karmesin","doi":"10.1109/PLASMA.1994.589034","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.589034","url":null,"abstract":"Plasma physics covers a wide variety of phenomena that are beyond the reach of symbolic mathematics, and for which experiments are often difficult. It is necessary to rely on computer experiments to test theories and understand the data. The authors describe progress in constructing a portable parallel Particle in Cell (PIC) code for three dimensional plasma simulations, and initial physics results using it for the Global Heliosphere problem. The code is designed to scale well to large parallel machines to take advantage of the fastest computers that are likely to be found in the foreseeable future. It is designed to allow the user to do a straight fluid (MHD) simulation, a kinetic PIC simulation to sample the velocity-space behavior of a system or a FLIP PIC simulation to model a low dissipation continuum fluid. It is designed to allow as much as possible of the algorithm to be written in dimension-independent style to allow the code to be used in 1, 2 or 3 dimensional systems. It is designed to be able to handle moderately complex geometries efficiently through the use of multiple patches, each of which is a deformable logically cartesian mesh. It is designed for several types ofmore » portability: to different numerics, physics, architectures, and people.« less","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124582988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Collisional Plasmas: Monte Carlo Calculations Without Samplinq Errors","authors":"D. Lemons, M.E. Jones","doi":"10.1109/PLASMA.1994.588681","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588681","url":null,"abstract":"","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114591462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studies Of A Pre-bunched Backward Wave Oscillator","authors":"C. Alexander, D. Shiffler","doi":"10.1109/PLASMA.1994.589069","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.589069","url":null,"abstract":"Among various high-power microwave sources, multiwave Cerenkov Generators (MWCGs) developed by Bugaev et al., High Current E1ec:tronics Institute, Russia, have attained top data of output. Radiation powers 3 GW at wave length 9.7 mm and efficiency 20 % were reported. Here a large mean diameter D of the slow wave structure (SWS) is the key point. Although the physical processes involved in the MWCGs are complicated, we here design a large diameter backward wave oscillator (LDBWO) operating at 24 GHz high-power microwaves without decreasing D. The inner radius of the metal surface of the SWS is assumed to vary sinusoidally as R(z)=R0+hcos(2Xz/z ) . The oscillation frequency is raised by cfloosing carefully small values of z o and h. Numerical study is made within the scope of linear pinch point analysis [1 1 for a SWS available in 24 GHz LD-BWO. Especially, we find that there exists a starting energy in addition to starting current in electron beam for initiating microwave oscillation, if the finite length L of SWS is taken into account. The optimized size parameters of SWS are as follows: RO=30 mm, h=1.7 mm, zo=3.4 mm, L=70z -238 mm and annular beam radius R -26.7 mm. !$he beam energy V -65-100 keV an$the beam current Ib up to P-kA are assumed. For Vb=65 keV, I m ( a ) C O , no matter how large Ib would be. No oscillations can be expected. The starting energy is found to be 76.5 keV and it is a decreasing function of L. It must be noted that the starting energy is not the sufficient condition, but the necessary condition for starting oscillation. Additional condition is that the radiation must grow up against the leakage at the both ends. This condition gives the starting current that is increasing function of the leakage. Intensity of output radiation from the designed LD-BWO is expected to be weak, because of small h. However, the output can be drastically enhanced, in the case that the coupling of the radiation with anomalous Doppler electron cyclotron resonance exists. Our exper ment for high-power, high-efficiency oscil ation is presented elsewhere. 5Pll","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116167032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulations And Measurements Of Alumina Particles In Plasma Spraying","authors":"W. H. Zhuang, H.F. Chen, K. Etemadi, D. Benenson","doi":"10.1109/PLASMA.1994.588982","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588982","url":null,"abstract":"A plasma spraying torch (Miller SG-100) has been studied by numerical modeling and Laser Doppler Velocimetry (LDV) techniques. Results are presented for axisymmetric turbulent argon plasma jets flowing into a cold air environment with the injection of alumina particles. The mathematical model involves the simultaneous solution of the continuity, momentum and energy equations for the plasma jet, and the dynamics and heat transfer of the particles in the plasma. Calculations are performed using the both parabolic and elliptic approaches. Turbulent effects are represented by the k-E model. The turbulent dispersion effect on the particles is also included. Coupling between the plasma jet and the particles is considered. -At a current of 900 A, plasma temperatures determined by modeling are compared with experimental results [l]. The difference is less than 4% at a distance less than 2 cm from the nozzle exit. At longer distance, plasma temperatures, obtained from modeling are about 3040% higher than those measured in [I] . At a current of 300 A, particle velocities obtained by the simulation are compared to LDV measurements with single and double injection. At a distance of 5.2 cm from the torch nozzle exit, particle velocities show a peak off-axis profile as measured by L,DV and as calculated by numerical modeling. Particle velocities determined from modeling are 20% higher than those measured by LDV at the axis. Differences between particle velocities determined from the parabolic and elliptic approaches are within 5%.","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116343574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parametric Studies Of Electron-energy -distribution-function And Rate Constants For Plasma-etching Reactors","authors":"J. Shon, E. Meeks, R. Kee","doi":"10.1109/PLASMA.1994.588746","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588746","url":null,"abstract":"The resulting reaction-rate coefficients are used to generate standard Arrhenius fits for the rate constants as a function of average electron energy. These reaction-rate coefficients are then employed in a plasma reactor model through a Chemkin interface. Results from the reactor model indicate the dependence of ion, electron, and neutral species concentrations on the assumptions inherent in the reactionrate determinations. We present differences between results","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"898 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116391522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect On The Efficiency Of Plasmochemical Reaction By Electrodynamics Of Nanosecond Corona Discharge","authors":"R. Amirov, Y. Desyaterik, I. Samoilov, A. V. Shepelin","doi":"10.1109/PLASMA.1994.588855","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588855","url":null,"abstract":"","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123996136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repetitively Pulsed Power For Meat Pasteurization","authors":"E. Patterson, R. Kaye, E. Neau","doi":"10.1109/PLASMA.1994.588901","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588901","url":null,"abstract":"","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126136251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement Of Shear Alfven Waves In The Lapd Device","authors":"W. Gekelman, D. Leneman, J. Maggs","doi":"10.1109/PLASMA.1994.588696","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588696","url":null,"abstract":"","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129894215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence Of Ponderomotive Force For Inductive Plasma Sources","authors":"T. Rognlien, G.J. DcPeso, D. Hewett, V. Vahedi","doi":"10.1109/PLASMA.1994.588844","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588844","url":null,"abstract":"","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128365324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microwave Plasma Discharge Produced And Sustained By The Surface Wave Propagating Along A Metal Wire","authors":"N. Azarenkov, I. Denisenko, K. Ostrikov","doi":"10.1109/PLASMA.1994.588701","DOIUrl":"https://doi.org/10.1109/PLASMA.1994.588701","url":null,"abstract":"A theoretical model of the plasma discharge in a metal cylinder pumped by an operating gas of an arbitrary nature is presented. The ionization is carried out by the surface wave (SW) propagating along a coaxial metal wire. The model includes the local dispersion relation, the energy balance equation, and the relation between the absorbed power per unit length and the local plasma density. Two typical regimes of the discharge are analyzed. In both regimes the axial and radial profiles of the plasma density of the electromagnetic field components and of the SW intensity are obtained. The possible use of the obtained results in plasma technology are discussed.","PeriodicalId":254741,"journal":{"name":"Proceedings of 1994 IEEE 21st International Conference on Plasma Sciences (ICOPS)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127163600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}