Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.166087
O. Ishihara
Charged particles in random electric fields are known to diffuse over the phase velocity resonant layer in velocity space, whereas charged particles placed in a sheared magnetic field diffuse over the mode rational surfaces due to E*B random fluctuations. The author has studied in detail the transition of particle diffusion in turbulent fields from the quasilinear (constant diffusion rate) to the nonlinear (time dependent rate) regime by numerical experiments with test particles. The author has observed that the particle diffusion rate deviates from the quasilinear value and depends on the time at which the amplitude of the random field becomes larger. Such a transition from quasilinear to nonlinear diffusion is observed without particle loss from the resonance region. The time-dependent diffusion coefficient can be explained by the effect of retarded friction caused by turbulent fluctuations.<>
{"title":"Particle diffusion in turbulent fields: transition from quasilinear to nonlinear stage","authors":"O. Ishihara","doi":"10.1109/PLASMA.1989.166087","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.166087","url":null,"abstract":"Charged particles in random electric fields are known to diffuse over the phase velocity resonant layer in velocity space, whereas charged particles placed in a sheared magnetic field diffuse over the mode rational surfaces due to E*B random fluctuations. The author has studied in detail the transition of particle diffusion in turbulent fields from the quasilinear (constant diffusion rate) to the nonlinear (time dependent rate) regime by numerical experiments with test particles. The author has observed that the particle diffusion rate deviates from the quasilinear value and depends on the time at which the amplitude of the random field becomes larger. Such a transition from quasilinear to nonlinear diffusion is observed without particle loss from the resonance region. The time-dependent diffusion coefficient can be explained by the effect of retarded friction caused by turbulent fluctuations.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130292561","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.166236
B. Poole, B. Chang, J. F. Camacho
Analytic computations and particle-in-cell (PIC) code simulations for the interaction of an intense relativistic electron beam (REB) and a plasma have been carried out. In the simulations, a fast risetime ( approximately 5 ns) 10-kA REB (1 MeV) was injected into a plasma-filled waveguide immersed in an axial magnetic field. Beam transport and microwave generation by beam-plasma instabilities were investigated in both the infinite- and finite-B-field cases. In the finite-B-field case, both the two-stream and cyclotron instabilities were important. Calculations of charge and current neutralization of the REB were performed in the intense beam regime. These calculations provided the appropriate parameters for the linear dispersion relation of the system, which was solved to determine the nature of the instabilities. For large magnetic fields the linearly unstable waves on the lower branch of the dispersion curve can backscatter off the accumulation of plasma electrons at the beam front produced in the charge neutralization process. These backscattered waves can then mix with the original unstable wave in a three-wave process to produce a wave on the upper branch of the dispersion curve at a higher-frequency. Still higher frequencies can be produced by a cascading of wave-mixing processes.<>
{"title":"Interaction of an intense relativistic electron beam with a plasma-filled waveguide in a magnetic field","authors":"B. Poole, B. Chang, J. F. Camacho","doi":"10.1109/PLASMA.1989.166236","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.166236","url":null,"abstract":"Analytic computations and particle-in-cell (PIC) code simulations for the interaction of an intense relativistic electron beam (REB) and a plasma have been carried out. In the simulations, a fast risetime ( approximately 5 ns) 10-kA REB (1 MeV) was injected into a plasma-filled waveguide immersed in an axial magnetic field. Beam transport and microwave generation by beam-plasma instabilities were investigated in both the infinite- and finite-B-field cases. In the finite-B-field case, both the two-stream and cyclotron instabilities were important. Calculations of charge and current neutralization of the REB were performed in the intense beam regime. These calculations provided the appropriate parameters for the linear dispersion relation of the system, which was solved to determine the nature of the instabilities. For large magnetic fields the linearly unstable waves on the lower branch of the dispersion curve can backscatter off the accumulation of plasma electrons at the beam front produced in the charge neutralization process. These backscattered waves can then mix with the original unstable wave in a three-wave process to produce a wave on the upper branch of the dispersion curve at a higher-frequency. Still higher frequencies can be produced by a cascading of wave-mixing processes.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129219454","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.166141
B. Freeman, D. Rickel
Results have been obtained from initial experiments in which a small plasma focus was used to drive DT microballoons. The DT microballoons were 1 mm in diameter and contained 75 atm of DT gas in a 50% mixture. The plasma focus driver achieves a maximum current of approximately 1 MA from its 20-kV, 72-kJ capacitor bank. The plasma sheath was formed from deuterium, helium, and argon for those tests. After several conditioning shots using the gas for the experiment, the microballoons were inserted into the focus region through an air lock in the device's anode, to avoid any electrical gradient between the positive electrode and the target.<>
{"title":"Preliminary plasma focus driven DT microballoon experiments","authors":"B. Freeman, D. Rickel","doi":"10.1109/PLASMA.1989.166141","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.166141","url":null,"abstract":"Results have been obtained from initial experiments in which a small plasma focus was used to drive DT microballoons. The DT microballoons were 1 mm in diameter and contained 75 atm of DT gas in a 50% mixture. The plasma focus driver achieves a maximum current of approximately 1 MA from its 20-kV, 72-kJ capacitor bank. The plasma sheath was formed from deuterium, helium, and argon for those tests. After several conditioning shots using the gas for the experiment, the microballoons were inserted into the focus region through an air lock in the device's anode, to avoid any electrical gradient between the positive electrode and the target.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125353271","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.165988
D. Kalluri
It is known that a sudden creation of a plasma medium of plasma frequency omega /sub p/ splits a traveling wave of frequency omega /sub 0/ into two new waves of frequencies omega /sub 1.2/=+or-( omega /sub 0//sup 2/+ omega /sub p//sup 2/)/sup 1/2/. The negative value for the frequency indicates a reflected wave. The effect of a sudden collapse of the plasma medium on a traveling wave of frequency omega /sub 0/ has been shown by the author to be the creation of two new waves of frequencies omega /sub 1.2/=+or-( omega /sub 0//sup 2/- omega /sub p//sup 2/)/sup 1/2/. These are propagating waves only if omega /sub 0/> omega /sub p/. The power in the reflected wave has a maximum of 3.7% of the power in the incident wave. The variation in the frequencies of the new waves and power carried by them with the incident wave frequency is shown. A numerical solution has been obtained for the case of a gradual collapse of the plasma medium. For the case of a slow decay of the particle density, an approximate WKB-type solution has been obtained.<>
{"title":"Effect of switching-off of a plasma medium on a traveling wave","authors":"D. Kalluri","doi":"10.1109/PLASMA.1989.165988","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.165988","url":null,"abstract":"It is known that a sudden creation of a plasma medium of plasma frequency omega /sub p/ splits a traveling wave of frequency omega /sub 0/ into two new waves of frequencies omega /sub 1.2/=+or-( omega /sub 0//sup 2/+ omega /sub p//sup 2/)/sup 1/2/. The negative value for the frequency indicates a reflected wave. The effect of a sudden collapse of the plasma medium on a traveling wave of frequency omega /sub 0/ has been shown by the author to be the creation of two new waves of frequencies omega /sub 1.2/=+or-( omega /sub 0//sup 2/- omega /sub p//sup 2/)/sup 1/2/. These are propagating waves only if omega /sub 0/> omega /sub p/. The power in the reflected wave has a maximum of 3.7% of the power in the incident wave. The variation in the frequencies of the new waves and power carried by them with the incident wave frequency is shown. A numerical solution has been obtained for the case of a gradual collapse of the plasma medium. For the case of a slow decay of the particle density, an approximate WKB-type solution has been obtained.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125409323","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.166158
S. Ahn, A. Ganguly
The nonlinear evolution of the gyrotron backward wave oscillator (gyro-BWO) has been investigated numerically in the presence of a tapered axial magnetic field. The set of coupled nonlinear differential equations that govern the self-consistent evolution of the TE modes and the trajectories of an ensemble of electrons in a gyrotron have been solved subject to boundary conditions for both the usual BWO (power extracted at the input end) and the reflection-type BWO (power extracted at the input end) and the reflection-type BWO (power extracted in the forward direction) configurations. The space-charge effects were neglected. The calculated saturation efficiency is about 10-15% in the K/sub a/-band with rectangular TE/sub 10/ modes and near 104 GHz with cylindrical TE/sub 10/ modes. However, the efficiency can be greatly enhanced (>30%) by tapering the magnetic field. The frequency of the oscillator can be magnetically tuned over a 15% bandwidth. Beam thermal effects have also been investigated.<>
{"title":"Optimization of the efficiency in gyrotron backward wave oscillator model via tapered axial magnetic field","authors":"S. Ahn, A. Ganguly","doi":"10.1109/PLASMA.1989.166158","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.166158","url":null,"abstract":"The nonlinear evolution of the gyrotron backward wave oscillator (gyro-BWO) has been investigated numerically in the presence of a tapered axial magnetic field. The set of coupled nonlinear differential equations that govern the self-consistent evolution of the TE modes and the trajectories of an ensemble of electrons in a gyrotron have been solved subject to boundary conditions for both the usual BWO (power extracted at the input end) and the reflection-type BWO (power extracted at the input end) and the reflection-type BWO (power extracted in the forward direction) configurations. The space-charge effects were neglected. The calculated saturation efficiency is about 10-15% in the K/sub a/-band with rectangular TE/sub 10/ modes and near 104 GHz with cylindrical TE/sub 10/ modes. However, the efficiency can be greatly enhanced (>30%) by tapering the magnetic field. The frequency of the oscillator can be magnetically tuned over a 15% bandwidth. Beam thermal effects have also been investigated.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126623180","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.166058
P. Parks
Fine-scale striations, with alternating rows of bright and dark zones, have been observed in the ablation clouds of carbon pellets injected into the TEXT tokamak. The striations extend along the magnetic field for about 1 cm with quite regular cross-field variations characterized by a wavelength of a few millimeters. It is proposed that the striations are the manifestation of the saturated state of growing fluctuations inside the cloud. The instability is generated by E*B rotation of the ablation cloud. The outward centrifugal force points down the ablation density gradient, inducing the Rayleigh-Taylor instability. The instability is not present for wave numbers along the field lines, which may explain why the striations are long and uniform in that direction. The E field develops inside the ablation cloud as a result of cold electron return currents that are induced to cancel the incoming hot plasma electron current streaming along the lines.<>
{"title":"Carbon pellet cloud striations","authors":"P. Parks","doi":"10.1109/PLASMA.1989.166058","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.166058","url":null,"abstract":"Fine-scale striations, with alternating rows of bright and dark zones, have been observed in the ablation clouds of carbon pellets injected into the TEXT tokamak. The striations extend along the magnetic field for about 1 cm with quite regular cross-field variations characterized by a wavelength of a few millimeters. It is proposed that the striations are the manifestation of the saturated state of growing fluctuations inside the cloud. The instability is generated by E*B rotation of the ablation cloud. The outward centrifugal force points down the ablation density gradient, inducing the Rayleigh-Taylor instability. The instability is not present for wave numbers along the field lines, which may explain why the striations are long and uniform in that direction. The E field develops inside the ablation cloud as a result of cold electron return currents that are induced to cancel the incoming hot plasma electron current streaming along the lines.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122971198","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.166083
K. Mizuno, P. Young, W. Seka, R. Bahr, J. S. De Groots, R. P. Drake, K. Estabrook, S. Kawata
Microwave experiments and computer simulations have shown that the ion acoustic parametric decay instability (IADI) can produce a significant number of hot electrons in a large-scale plasma. These hot electrons are a concern in proposed inertial confinement fusion (ICF) studies because they preheat the target and degrade compression. The ion wave turbulence excited by IADI will also be the source of anomalous resistivity, so that thermal electrons are strongly heated due to anomalous Joule heating. The authors have extensively studied the IADI in laser-pellet interactions. They have shown that the IADI threshold is quite low, so that IADI is potentially important in laser-driven fusion pellets. They have also shown that the ionic charge state Z can be measured using the Stokes signal. IADI is also a useful tool for plasma diagnostics at the critical surface. The experimental procedure is briefly described.<>
{"title":"Ion acoustic decay instabilities in laser pellet interactions","authors":"K. Mizuno, P. Young, W. Seka, R. Bahr, J. S. De Groots, R. P. Drake, K. Estabrook, S. Kawata","doi":"10.1109/PLASMA.1989.166083","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.166083","url":null,"abstract":"Microwave experiments and computer simulations have shown that the ion acoustic parametric decay instability (IADI) can produce a significant number of hot electrons in a large-scale plasma. These hot electrons are a concern in proposed inertial confinement fusion (ICF) studies because they preheat the target and degrade compression. The ion wave turbulence excited by IADI will also be the source of anomalous resistivity, so that thermal electrons are strongly heated due to anomalous Joule heating. The authors have extensively studied the IADI in laser-pellet interactions. They have shown that the IADI threshold is quite low, so that IADI is potentially important in laser-driven fusion pellets. They have also shown that the ionic charge state Z can be measured using the Stokes signal. IADI is also a useful tool for plasma diagnostics at the critical surface. The experimental procedure is briefly described.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123084901","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.165953
J. Margot-Chaker, M. Moisan, C. Barbeau
Summary form only. The authors have been conducting an extensive experimental study on one of the key parameters of high-frequency discharges, theta , which represents the average power dissipated to maintain an electron-ion pair. A self-consistent model (coupling the wave and plasma equations) can be used to predict the observed behavior of theta , especially in regard to whether the similarity law theta /p versus pa is obeyed. However, a closer examination of the experimental results shows discrepancies that could be connected with the frequency dependence of the electron energy distribution function (EEDF). In this model, another important factor that reflects the EEDF is the effective collision frequency for momentum transfer, nu . Knowledge of both theta and nu allows the discharge to be modeled completely, since the axial distribution of the electron density can then be predicted. An effective electric field intensity value can be estimated from the observed theta and nu , and the behavior of the EEDF with frequency can be qualitatively deduced.<>
{"title":"A critical review based on experiments of the self-consistent modelling leading to the power balance equation of surface waves produced plasmas","authors":"J. Margot-Chaker, M. Moisan, C. Barbeau","doi":"10.1109/PLASMA.1989.165953","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.165953","url":null,"abstract":"Summary form only. The authors have been conducting an extensive experimental study on one of the key parameters of high-frequency discharges, theta , which represents the average power dissipated to maintain an electron-ion pair. A self-consistent model (coupling the wave and plasma equations) can be used to predict the observed behavior of theta , especially in regard to whether the similarity law theta /p versus pa is obeyed. However, a closer examination of the experimental results shows discrepancies that could be connected with the frequency dependence of the electron energy distribution function (EEDF). In this model, another important factor that reflects the EEDF is the effective collision frequency for momentum transfer, nu . Knowledge of both theta and nu allows the discharge to be modeled completely, since the axial distribution of the electron density can then be predicted. An effective electric field intensity value can be estimated from the observed theta and nu , and the behavior of the EEDF with frequency can be qualitatively deduced.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125734000","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.166202
M. McCaughey, M. Kushner
Commercial and research devices using electric discharges (low-temperature, partially ionized plasmas) are inevitably contaminated by solid particulate matter. The plasma is therefore composed of two phases: solid and gas. If the size of the particulate matter is comparable to or larger than the Debye length, a sheath will develop at the surface of the dust in a manner similar to that at the surface of a macroscopic object in contact with the plasma. The sheath around the particulate matter occludes current flow and perturbs the electron energy distribution function (EEDF). The former process can lead to discharge instabilities; the latter can detrimentally effect the electron impact rate coefficients. To assess the impact of charged particulate matter on electron transport coefficients, a hybrid molecular-dynamics-Monte-Carlo simulation has been developed. The EEDF is obtained by integrating the trajectory of electrons in the sheath regions of the dust while simultaneously applying Monte Carlo techniques for collisions with gas atoms or molecules. A self-consistent value is obtained for the sheath potential at the surface of the dust by requiring that equal fluxes of electrons and ions flow to the surface. Electrons striking the dust are removed from the simulation, thereby effectively cutting off the EEDF at the sheath potential.<>
{"title":"Electron swarms in two-phase plasmas","authors":"M. McCaughey, M. Kushner","doi":"10.1109/PLASMA.1989.166202","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.166202","url":null,"abstract":"Commercial and research devices using electric discharges (low-temperature, partially ionized plasmas) are inevitably contaminated by solid particulate matter. The plasma is therefore composed of two phases: solid and gas. If the size of the particulate matter is comparable to or larger than the Debye length, a sheath will develop at the surface of the dust in a manner similar to that at the surface of a macroscopic object in contact with the plasma. The sheath around the particulate matter occludes current flow and perturbs the electron energy distribution function (EEDF). The former process can lead to discharge instabilities; the latter can detrimentally effect the electron impact rate coefficients. To assess the impact of charged particulate matter on electron transport coefficients, a hybrid molecular-dynamics-Monte-Carlo simulation has been developed. The EEDF is obtained by integrating the trajectory of electrons in the sheath regions of the dust while simultaneously applying Monte Carlo techniques for collisions with gas atoms or molecules. A self-consistent value is obtained for the sheath potential at the surface of the dust by requiring that equal fluxes of electrons and ions flow to the surface. Electrons striking the dust are removed from the simulation, thereby effectively cutting off the EEDF at the sheath potential.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"145 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120930980","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}
Pub Date : 1989-05-22DOI: 10.1109/PLASMA.1989.165964
R. Hawke, A. Susoeff, J. Asay, C. Hall, C. Konrad, R. Hickman, J. Sauvé
Summary form only. The use of a two-stage light-gas gun (2SLGG) as a preaccelerator in combination with a railgun is expected to reduce barrel ablation significantly and improve overall performance. In particular, the use of a hydrogen 2SLGG provides injection velocities of 6 to 8 km/s and a pure hydrogen environment immediately behind the projectile as it enters a railgun. To continue acceleration of the projectile, a plasma armature must be formed. The authors have explored two methods of converting a portion of the fast-moving hydrogen gas into a plasma armature. In particular, they carried out tests in which armatures were formed and used to further accelerate a projectile.<>
{"title":"Armature formation and performance in a railgun using a two-stage light-gas gun injector","authors":"R. Hawke, A. Susoeff, J. Asay, C. Hall, C. Konrad, R. Hickman, J. Sauvé","doi":"10.1109/PLASMA.1989.165964","DOIUrl":"https://doi.org/10.1109/PLASMA.1989.165964","url":null,"abstract":"Summary form only. The use of a two-stage light-gas gun (2SLGG) as a preaccelerator in combination with a railgun is expected to reduce barrel ablation significantly and improve overall performance. In particular, the use of a hydrogen 2SLGG provides injection velocities of 6 to 8 km/s and a pure hydrogen environment immediately behind the projectile as it enters a railgun. To continue acceleration of the projectile, a plasma armature must be formed. The authors have explored two methods of converting a portion of the fast-moving hydrogen gas into a plasma armature. In particular, they carried out tests in which armatures were formed and used to further accelerate a projectile.<<ETX>>","PeriodicalId":165717,"journal":{"name":"IEEE 1989 International Conference on Plasma Science","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124909251","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：