Filters








33 Hits in 6.2 sec

Modeling of ionizing hypersonic flows in nonequilibrium

F. Grasso, G. Capano
1995 Journal of Spacecraft and Rockets  
For weakly ionized flows, an ambipolar diffusion coefficient is introduced to describe ion diffusion.  ...  It must be pointed out that most of the nonequilibrium hyper- sonic flow simulations with ionization consider the flow weakly ionized, and plasmadynamic effects are generally neglected.  ... 
doi:10.2514/3.26599 fatcat:yjipkq7vf5attjruwr744kyusm

Effectiveness of a Magnetohydrodynamics System for Mars Entry

Minkwan Kim, Iain D. Boyd
2012 Journal of Spacecraft and Rockets  
In Eq. (24), the Hall and ion- slip effects are considered.  ...  Flowfield Equations The hypersonic flow condition causes many physical phenomena in the flowfield including chemical nonequilibrium, vibrational and electronic excitation, thermal nonequilibrium, and ionization  ... 
doi:10.2514/1.a32256 fatcat:t7kahcgylbdj7gxi6nwrgjougy

Modeling Plasma via Electron Impact Ionization

Joseph Shang
2018 Aerospace (Basel)  
Variable and potential plasma applications in aerospace engineering are exemplified by ion thrusters, flow control by plasma actuator, enhanced ignition and combustion stability.  ...  The fundamental ionization mechanisms by electron impact consist of electron secondary mission and the cascading process.  ...  In short, the computational simulations by the Lagrangian formulation are analyzing plasmadynamics in the rarefied gas regime, and the computational resource requirement is extremely demanding.  ... 
doi:10.3390/aerospace5010002 fatcat:vfvp2ptqcva4lez24orgql5yhm

Kinetic and Continuum Simulations of Electromagnetic Control of a Simulated Reentry Flow

Hiroshi Katsurayama, Masaaki Kawamura, Atsushi Matsuda, Takashi Abe
2008 Journal of Spacecraft and Rockets  
Conclusions \ weakly ionized rarefied supersonic flow of K, = 0.05 and M = 1.7 past a blunt body was simulated using DSMC and NS computation.  ...  and electron-ion collisional frequencies [18].  ... 
doi:10.2514/1.31702 fatcat:x2ypek3iqvemfkf64zgimk4v6a

Experimental Verification of Heat-Flux Mitigation by Electromagnetic Fields in Partially-Ionized-Argon Flows

Ali Gülhan, Burkard Esser, Uwe Koch, Frank Siebe, Johannes Riehmer, Domenico Giordano, Detlev Konigorski
2009 Journal of Spacecraft and Rockets  
impetus to computational investigations of ionized super- and hypersonic flowfields in the presence of electromagnetic fields.  ...  Expectedly, the total electromagnetic field (externally applied plus induced) influences the path of ions and free electrons and leads to a change in the topology of the flowfield in such a way that the  ... 
doi:10.2514/1.39256 fatcat:ebpjydtdh5h3pnkcv62ooqxjlm

Modeling of the Electrogun Metal Vapor Plasma Discharge

Laxminarayan L. Raja, Philip L. Varghese, Dennis E. Wilson
1997 Journal of thermophysics and heat transfer  
= plasma nonideality parameter e = correction parameter for electron-electron scattering ion,s = lowering of ionization energy of heavy species s, J ion,s = ionization energy of heavy species  ...  For a partially ionized plasma, electron collisions with both neutral atoms and ions determine the electrical conductivity.  ... 
doi:10.2514/2.6273 fatcat:n6dng76w4bf3rlo3gvblxxc64q

Magnetic field effects on the computed flow over a Mars return aerobrake

GRANT PALMER
1993 Journal of thermophysics and heat transfer  
The sharp rise in the atomic nitrogen mole fraction along the stagnation line near the body is due to the drop in both the ions and electron mole fractions in this re- gion.  ...  Candler, G., “The Computation of Weakly Ionized Hypersonic Flows in Thermo-Chemical Nonequilibrium,” Ph.D. Dissertation, Stanford Univ., Stanford, CA, June 1988. *Gnoffo, P. A., Gupta, R.  ... 
doi:10.2514/3.419 fatcat:633fftgpere53bou55arjhkn3m

Energy Partitions in Inductively Heated Plasma Sources for Reentry Simulations

S. Lenzner, M. Auweter-Kurtz, J. Heiermann, P. C. Sleziona
2000 Journal of thermophysics and heat transfer  
Lotz, W., “Electron-Impact Ionization Cross-Sections and Ionization Rate Coefficients for Atoms and Ions from Hydrogen to Calcium,” Zeitschrift fiir Physik, Vol. 216, 1968, pp. 241-247.  ...  In Fig. 3, the computational results of the electron and heavy par- ticle temperatures are shown.  ... 
doi:10.2514/2.6536 fatcat:o7s4b6shlrd5xlhjis5axfvijy

High-enthalpy hypersonic flows

Joseph J. S. Shang, Hong Yan
2020 Advances in Aerodynamics  
When the air mixture is ionized to become an electrically conducting medium, the governing physics now ventures into the regimes of quantum physics and electromagnetics.  ...  Nearly all illuminating classic hypersonic flow theories address aerodynamic phenomena as a perfect gas in the high-speed range and at the upper limit of continuum gas domain.  ...  Acknowledgements In preparation of the manuscript, authors have received constant encouragement and inspiration for pursuing of excellence from Prof.  ... 
doi:10.1186/s42774-020-00041-y fatcat:vmsjhvdqunbfbclso3ohs7cdiy

Numerical Studies of Magnetohydrodynamic Flow Control Considering Real Wall Electrical Conductivity

Takayasu Fujino, Yusuke Matsumoto, Jiro Kasahara, Motoo Ishikawa
2007 Journal of Spacecraft and Rockets  
From the of the electron Hall parameter, the ion Hall parameter 1s estimated at the order of O.1, and so the product of electron and ion Hall parameters, whic!  ...  The idea of the MHD flow control is that the Lorentz force, which is induced by applying 626 FUJINO ET AL the magnetic field to the weakly ionized plasma flow in the shock layer, decelerates the flow velocity  ... 
doi:10.2514/1.25824 fatcat:5xcad3bumvc4pivb32kqccfdqu

Multigrid Method for Numerical Simulation of Faraday Probe Measurements

Jeremiah J. Boerner, Iain D. Boyd
2009 IEEE Transactions on Plasma Science  
arcana of electron plasma measurements.  ...  Mom cares and worries and prays for the best, and doesn't let me forget the greats in my past.  ...  Most plasmas are partially ionized, meaning that the bulk plasma consists of neutral gas particles, ions, and electrons.  ... 
doi:10.1109/tps.2009.2033358 fatcat:gpfa3qm73za5pm2rv2g5h5jjle

A Global Enhanced Vibrational Kinetic Model for Radio-Frequency Hydrogen Discharges and Application to the Simulation of a High Current Negative Hydrogen Ion Source [article]

Sergey N. Averkin
2017 arXiv   pre-print
The volume-averaged steady-state continuity equations coupled with the electron energy equation, the total energy equation and heat transfer to the chamber walls are solved simultaneously to obtain the  ...  negative hydrogen ion production region where H^- are generated by the dissociative attachment of low energy electrons to rovibrationally excited hydrogen molecules.  ...  species and the ions are produced by ionization in the bulk, then continuity and momentum equations for positive in addition, the electrons are in Boltzmann equilibrium and the background gas has a uniform  ... 
arXiv:1709.07071v1 fatcat:efmkchv6nzbxxkkbztlunhhwye

Computational Study of Impregnated Ablator for Improved Magnetohydrodynamic Heat Shield

Nicholas J. Bisek, Ryan Gosse, Jonathan Poggie
2013 Journal of Spacecraft and Rockets  
The concept relies on magnetohydrodynamics to generate a force in the weakly ionized postshock air, which decelerates the incoming flow.  ...  temperature, K velocity vector (u, v, w) degree of ionization, n,/N Hall parameter (electrons), 4B Hall parameter (ions) volume void fraction permeability of free space, 42 x 10~’ N/A?  ... 
doi:10.2514/1.a32357 fatcat:uvxqryuktfahpixmohzdshscti

DYNAMICS OF PLASMA DISCHARGES USED FOR SPACE PROPULSION

Christopher V Young, Mark A Cappelli
2016 Zenodo  
The collection of plasma oscillations, instabilities, and turbulent fluctuations present in Hall thrusters make for rich electron and ion dynamic behavior that is the subject of this investigation.  ...  fundamental experimental and computational studies persist.  ...  impact ionization and excitation, radiative decay and local electron and ion transport mechanisms.  ... 
doi:10.5281/zenodo.3831450 fatcat:s5odd262ungjhastfo2ljxtlze

Ion-Energy Diagnostics in an SPT-100 Plume from Thrust Axis to Backflow

Lyon B. King, Alec D. Gallimore
2004 Journal of Propulsion and Power  
These data uncovered the existence of high-energy ions departing the thruster at angles exceeding 90 deg from the thrust vector and continuing well into the backflow region of the plume.  ...  With this instrument ion energy was measured over a complete 360-deg circumference about the thruster at 0.5-m radius from the exit plane and over a total inclusive arc of 260 deg at 1.0-m radius.  ...  , Sang-wook Kim, and George Williams for their discussions in the preparation of this manuscript.  ... 
doi:10.2514/1.1427 fatcat:opa56ho7bjctveyq23roqiieii
« Previous Showing results 1 — 15 out of 33 results