Limitations on Mass Separation by the Weakly Ionized Plasma Centrifuge

1980 ◽  
Vol 35 (8) ◽  
pp. 883-893 ◽  
Author(s):  
M. M. B. Wijnakker ◽  
E. H. A. Granneman
Keyword(s):  
Magnetic Field ◽  
Viscous Dissipation ◽  
Axial Magnetic Field ◽  
Particle Temperature ◽  
Rotational Velocity ◽  
Heavy Particle ◽  
Pressure Rise ◽  
Mass Separation ◽  
Argon Discharge ◽  
Weakly Ionized

bstractA In weakly ionized argon and xenon rotating plasmas the rotational velocity and the temperature and pressure distribution have been measured. The stationary discharge is generated by two opposed cathode-anode configurations. The arc current of 100 A is drawn across an axial magnetic field up to 0.26 T. The filling pressure ijs varied between 1 and 10 torr. The rotational velocity is found to be proportional to the discharge current and the magnetic field and inversely proportional to the viscosity of the neutral gas. The rotational kinetic energies of the particles in the argon and xenon discharge are about equal. Because the temperature of the argon discharge is lower than that of the xenon discharge, the pressure rise in radial direction due to centrifugal forces is steeper for the former. A theoretical analysis taking into account viscous dissipation as the only heating mechanism yields a heavy particle temperature T which imposes an upper limit to the ratio X =½m υθ2/kT of order unity. The maximum attainable separation factor α is therefore limited in these types of centrifuges. Experimentally, in the parameter region studied, X is found not to exceed a value 0.4 in argon discharges and 0.2 in xenon discharges. A rough estimate shows that besides viscous dissipation other heating mechanisms are also important. Ohmic heating, for instance, is at least a factor 6 larger than the viscous dissipation.

Experimentelle Untersuchung der Rayleigh-Taylor-Instabilität eines rotierenden Wasserstoff-Lichtbogens im axialen Magnetfeld

1969 ◽  
Vol 24 (8) ◽  
pp. 1249-1258
Author(s):  
H Döbele
Keyword(s):  
Magnetic Field ◽  
Light Intensity ◽  
Growth Rates ◽  
Axial Magnetic Field ◽  
Rotational Velocity ◽  
Arc Plasma ◽  
Hollow Anode ◽  
Dissipative Effects ◽  
Periodic Fluctuations ◽  
Experimentelle Untersuchung

Abstract A hydrogen arc with a hollow anode in an axial magnetic field is subjected to Rayleigh-Taylor instabilities as a result of rotation due to the radial current components at the anode. These instabilities take the form of periodic fluctuations in the light intensity emitted from the boundary regions of the arc. The modes m = 4 to m = 7 which occur in succession with increasing magnetic field are identified by measuring the signal phases in end-on observation of the arc. The rotational velocity of the arc plasma is determined spectroscopically and comparison is made with the non-dissipative MHD theory, which yields growth rates ∼ .The deviations from this theory that were observed in this experiment are ascribed to dissipative effects.

Slippage phenomenon in hydromagnetic peristaltic rheology with hall current and viscous dissipation

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Aamir Ali ◽  
Sana Mumraiz ◽  
Hafiz Junaid Anjum ◽  
Saleem Asghar ◽  
Muhammad Awais
Keyword(s):  
Magnetic Field ◽  
Viscous Dissipation ◽  
Hall Current ◽  
Perturbation Technique ◽  
Pressure Rise ◽  
Biomedical Science ◽  
Slip Parameter ◽  
Peristaltic Activity ◽  
Bolus Size ◽  
Opposite Behavior

Abstract The current research explores the slippage phenomenon in hydromagnetic peristaltic activity of a non-Newtonian fluid with porous media in an asymmetric channel. The analysis is performed under the influence of thermal radiation, Hall current, Joule heating and viscous dissipation. The problem is formulated with the assumption of small Reynolds number and large wavelength. Analytical solutions are achieved through perturbation technique and the impacts of involved influential parameters are examined through graphs. It is observed that the pressure gradient rises with fourth grade fluid parameter and decreases with increasing phase difference. The pressure rise increases in pumping regime and decreases in co-pumping regime for increasing magnetic field parameter, whereas it has opposite effects for hall parameter. It is also noted that the velocity drops in the middle of the channel, while it increases near the boundaries for growing slip parameter and magnetic field parameters and it has the opposite behavior for hall and permeability parameters. The slip parameter increases the temperature of the fluid and decreases the concentration. Also, in trapping phenomena, the bolus size reduces by enlarging Deborah parameter. The present research has profound use in biomedical science, polymer technology and artificial heart polishing.

A Study of a Weakly Ionized Rotating Plasma

1979 ◽  
Vol 34 (6) ◽  
pp. 672-690 ◽  
Author(s):  
M. M. B. Wijnakker ◽  
E. H. A. Granneman ◽  
J. Kistemaker
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Pressure Distribution ◽  
Rotational Velocity ◽  
Symmetry Plane ◽  
Radial Pressure ◽  
Plasma Potential ◽  
Theoretical Treatment ◽  
Ion Temperature ◽  
Weakly Ionized

Abstract Measurements are reported on a weakly ionized rotating argon plasma generated by two identical gas discharges facing each other. In each discharge a current up to 100 A is drawn between a point-like cathode and a ring-shaped anode. Axial magnetic fields up to 0.26 T are applied. All measurements have been done at 1 torr.For magnetic field strengths below 0.17 T the plasma has a more or less uniform radial distribution; above 0.17 T a contracted plasma column is present along the axis of the cylinder. In the symmetry plane between the two discharges measurements have been done on the rotational velocity of neutrals and ions, the electron density and temperature, the ion temperature, the plasma potential and the radial pressure distribution. The rotational velocity, the plasma potential and the pressure distribution are also calculated. The theoretical treatment is based on the theory developed by Klüber and Wilhelm and Hong.In the low magnetic field case velocities of 700 m/sec are found for ions as well as neutrals. The agreement between theory and experiment is good in this case. At high magnetic fields, the ions and neutrals are found to have azimuthal velocities of 1900 and 700 m/sec, respectively.The radial pressure enhancement due to the centrifugal forces is found to be approximately a factor of two whereas the theory predicts only a factor of 1.2. In a discharge in which a mixture of argon and xenon is used a relative separation factor of 2.15 is found.

scholarly journals A simulation study of argon discharge in PIG ion source with axial magnetic field

2020 ◽  
Vol 1601 ◽  
pp. 022044
Author(s):  
Jie Li ◽  
Shaojia Ju ◽  
Aizhong Yue ◽  
Xiaolei Zhang ◽  
Hu Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Simulation Study ◽  
Axial Magnetic Field ◽  
Ion Source ◽  
Argon Discharge ◽  
Pig Ion Source

EXPANSION OF LASER-PRODUCED ION BEAMS IN AN AXIAL MAGNETIC FIELD

2002 ◽  
Vol 6 (4) ◽  
pp. 8
Author(s):  
J. Wolowski ◽  
J. Badziak ◽  
P. Parys ◽  
E. Woryna ◽  
J. Krasa ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Axial Magnetic Field ◽  
Ion Beams

A Slotless PM Variable Reluctance Resolver with Axial Magnetic Field

2021 ◽  
pp. 1-1
Author(s):  
Le Sun ◽  
Zhejun Luo ◽  
Jun Hang ◽  
Shichuan Ding ◽  
Wei Wang
Keyword(s):  
Magnetic Field ◽  
Axial Magnetic Field ◽  
Variable Reluctance

Analytical solution for unsteady flow behind ionizing shock wave in a rotational axisymmetric non-ideal gas with azimuthal or axial magnetic field

2021 ◽  
Vol 76 (3) ◽  
pp. 265-283
Author(s):  
G. Nath
Keyword(s):  
Magnetic Field ◽  
Shock Wave ◽  
Analytical Solution ◽  
Axial Magnetic Field ◽  
Order Approximation ◽  
Ideal Gas ◽  
Field Region ◽  
First Order ◽  
First Order Approximation ◽  
Flow Variables

Abstract The approximate analytical solution for the propagation of gas ionizing cylindrical blast (shock) wave in a rotational axisymmetric non-ideal gas with azimuthal or axial magnetic field is investigated. The axial and azimuthal components of fluid velocity are taken into consideration and these flow variables, magnetic field in the ambient medium are assumed to be varying according to the power laws with distance from the axis of symmetry. The shock is supposed to be strong one for the ratio C 0 V s 2 ${\left(\frac{{C}_{0}}{{V}_{s}}\right)}^{2}$ to be a negligible small quantity, where C 0 is the sound velocity in undisturbed fluid and V S is the shock velocity. In the undisturbed medium the density is assumed to be constant to obtain the similarity solution. The flow variables in power series of C 0 V s 2 ${\left(\frac{{C}_{0}}{{V}_{s}}\right)}^{2}$ are expanded to obtain the approximate analytical solutions. The first order and second order approximations to the solutions are discussed with the help of power series expansion. For the first order approximation the analytical solutions are derived. In the flow-field region behind the blast wave the distribution of the flow variables in the case of first order approximation is shown in graphs. It is observed that in the flow field region the quantity J 0 increases with an increase in the value of gas non-idealness parameter or Alfven-Mach number or rotational parameter. Hence, the non-idealness of the gas and the presence of rotation or magnetic field have decaying effect on shock wave.

Sign in / Sign up

Export Citation Format

Share Document