Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields
A general approach to Monte Carlo methods for Coulomb collisions is proposed. Its key idea is an approximation of Landau-Fokker-Planck (LFP) equations by Boltzmann equations of quasi-Maxwellian kind. Highfrequency fields are included into consideration and comparison with the well-known results are...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
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Цитувати: | Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields / A.V. Andriash, A.V. Bobylev, A.V. Brantov, V.Yu. Bychenkov, S.A. Karpov, I.F. Potapenko // Вопросы атомной науки и техники. — 2013. — № 4. — С. 233-237. — Бібліогр.: 14 назв. — англ. |
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irk-123456789-1121632017-01-18T03:04:00Z Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields Andriash, A.V. Bobylev, A.V. Brantov, A.V. Bychenkov, V.Yu. Karpov, S.A. Potapenko, I.F. Нелинейные процессы в плазменных средах A general approach to Monte Carlo methods for Coulomb collisions is proposed. Its key idea is an approximation of Landau-Fokker-Planck (LFP) equations by Boltzmann equations of quasi-Maxwellian kind. Highfrequency fields are included into consideration and comparison with the well-known results are given. Запропоновано загальний підхід до моделювання кулонівських зіткнень методом Монте-Карло. Основна ідея полягає в апроксимації системи рівнянь Ландау-Фоккера-Планка (ОФП) рівняннями Больцмана квазі- максвеллiвського виду. Також розглядаються високочастотні поля, і наводиться порівняння з отриманими раніше результатами. Предложен общий подход к моделированию кулоновских столкновений методом Монте-Карло. Основная идея заключается в аппроксимации системы уравнений Ландау-Фоккера-Планка (ЛФП) уравнениями Больцмана квазимаксвелловского вида. Также рассматриваются высокочастотные поля, и приводится сравнение с полученными ранее результатами. 2013 Article Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields / A.V. Andriash, A.V. Bobylev, A.V. Brantov, V.Yu. Bychenkov, S.A. Karpov, I.F. Potapenko // Вопросы атомной науки и техники. — 2013. — № 4. — С. 233-237. — Бібліогр.: 14 назв. — англ. 1562-6016 PACS: 52.25.Dg, 52.65.Ff, 52.65.Pp http://dspace.nbuv.gov.ua/handle/123456789/112163 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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Нелинейные процессы в плазменных средах Нелинейные процессы в плазменных средах |
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Нелинейные процессы в плазменных средах Нелинейные процессы в плазменных средах Andriash, A.V. Bobylev, A.V. Brantov, A.V. Bychenkov, V.Yu. Karpov, S.A. Potapenko, I.F. Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields Вопросы атомной науки и техники |
description |
A general approach to Monte Carlo methods for Coulomb collisions is proposed. Its key idea is an approximation of Landau-Fokker-Planck (LFP) equations by Boltzmann equations of quasi-Maxwellian kind. Highfrequency fields are included into consideration and comparison with the well-known results are given. |
format |
Article |
author |
Andriash, A.V. Bobylev, A.V. Brantov, A.V. Bychenkov, V.Yu. Karpov, S.A. Potapenko, I.F. |
author_facet |
Andriash, A.V. Bobylev, A.V. Brantov, A.V. Bychenkov, V.Yu. Karpov, S.A. Potapenko, I.F. |
author_sort |
Andriash, A.V. |
title |
Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields |
title_short |
Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields |
title_full |
Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields |
title_fullStr |
Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields |
title_full_unstemmed |
Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields |
title_sort |
stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields |
publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
publishDate |
2013 |
topic_facet |
Нелинейные процессы в плазменных средах |
url |
http://dspace.nbuv.gov.ua/handle/123456789/112163 |
citation_txt |
Stochastic simulation of the nonlinear kinetic equation with high-frequency electromagnetic fields / A.V. Andriash, A.V. Bobylev, A.V. Brantov, V.Yu. Bychenkov, S.A. Karpov, I.F. Potapenko // Вопросы атомной науки и техники. — 2013. — № 4. — С. 233-237. — Бібліогр.: 14 назв. — англ. |
series |
Вопросы атомной науки и техники |
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2025-07-08T03:29:05Z |
last_indexed |
2025-07-08T03:29:05Z |
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fulltext |
ISSN 1562-6016. ВАНТ. 2013. №4(86) 233
NONLINEAR PROCESSES IN PLASMA MEDIA
STOCHASTIC SIMULATION OF THE NONLINEAR KINETIC
EQUATION WITH HIGH-FREQUENCY ELECTROMAGNETIC FIELDS
A.V. Andriash1, A.V. Bobylev2, A.V. Brantov1,3, V.Yu. Bychenkov1,3, S.A. Karpov1,
I.F. Potapenko4
1All-Russia Research Institute of Automatics (VNIIA), Moscow, Russian Federation;
2Department of Mathematics, Karlstad University, Karlstad, Sweden;
3P.N. Lebedev Physics Institute, RAS, Moscow, Russian Federation;
4Keldysh Institute for Applied Mathematics, RAS, Moscow, Russian Federation
A general approach to Monte Carlo methods for Coulomb collisions is proposed. Its key idea is an
approximation of Landau-Fokker-Planck (LFP) equations by Boltzmann equations of quasi-Maxwellian kind. High-
frequency fields are included into consideration and comparison with the well-known results are given.
PACS: 52.25.Dg, 52.65.Ff, 52.65.Pp
INTRODUCTION
Numerical simulation of plasma dynamics on kinetic
level is a difficult problem. It is natural to use standard
splitting methods, i.e. to consider separately (a)
continuous motion of electrons and ions in external and
self-consistent electro-magnetic fields and (b) Coulomb
collisions. The splitting procedure is formally quite
similar to what we do in simulation of neutral gases by
Monte Carlo methods [1]. There is, however, a big
difference in the simulation of the first stage (a), which
is almost trivial (free molecular flow) for neutral gases.
The corresponding motion of charged particles,
described by Vlasov-Poisson or Vlasov-Maxwell kinetic
equations [2], is much more sophisticated. The particle
methods for solving these equations of "collisionless"
plasma are very well developed and discussed in
literature. We shall consider below only the second
stage (b), related to Coulomb collisions.
The spatially homogeneous kinetic equation for
Coulomb interaction were first published by
L.D. Landau in 1936 [3]. Beginning with its re-
discovery in the Fokker-Planck form in [4] a lot of work
is done on numerical methods for the LFP equations
based on finite difference schemes. Recent review on
that subject can be found in [5], it contains many
references. We are interested in this paper in methods,
which are very close to Discrete Simulation Monte
Carlo (DSMC) methods in rarefied gas dynamics [1].
The two well-known methods should be mentioned
first in that field [6] and [7]. The general approach to
DSMC methods for Boltzmann equation with long
range potentials and for Landau equation was proposed
in [8]. In the present paper we use another approach of
the method (see, for example, [9]), which looks simpler
for computer implementation. It looks quite natural to
approximate the Landau equation by the Boltzmann
equation with small-angle scattering and then to use any
known DSMC scheme [1] for simulation. This
approximation can be chosen in the quasi-Maxwellian
way, such that the collision frequency for the auxiliary
Boltzmann equation is constant. In the present paper we
choose the simplest, in our view, scattering law in that
class.
1. APPROXIMATION OF LANDAU
EQUATIONS BY BOLTZMANN
EQUATIONS
We consider an arbitrary spatially homogeneous
mixture of rarefied gases. Let { ( , ), = 1, ..., }if t i nv be
distribution functions of particles with masses
{ , = 1, ..., }im i n , respectively. The independent
variables 3R∈v and 0≥t stand for velocity and time,
respectively. Spatial densities { ( ), = 1, ..., }i t i nρ are
given by integrals
3
( ) = ( , ) = 1, ..., .i i
R
t d f t i nρ v v ,∫ (1)
The system of Boltzmann kinetic equations for
),( tif v reads
=1
= ( , ), , = 1, ..., ,
n
i
ij i j
j
f
Q f f i j n
t
∂
∂
∑ (2)
where
( )
( )
2
( , ) = , ( ) ( ) ( ) ( ) ,
= , S , 1
1
=
1
=
ij i j ij i j i j
i j j
i j
i j i
i j
Q f f d d g u f f f f
i j n
u
m m m u
m m
m m mu
m m
μ
μ
w ω ( ) v w v w
u ω
u v w , ω , , ..., ,
v v w ω ,
w v w ω .
′ ′ −
⋅
− = ∈ =
′ + +
+
′ + −
+
⎡ ⎤⎣ ⎦∫
(3)
Functions ),( μuijg are expressed by formulas
( , ) = ( , ) = ( , ),ij ji ijg u g u u uμ μ σ μ where ( , )ij uσ μ is
the differential cross section (in the center of mass
system of colliding particles of sort i and sort j) of
scattering at the angle 1.||),(arccos= ≤μμθ
The system of Boltzmann equations (2) is interesting
for us merely as a starting point to pass to the Landau
equations. For such transition one needs to choose a
special kind of functions ( , ).ijg u μ This choice is based
on the fact which has been proved many years ago [11].
ISSN 1562-6016. ВАНТ. 2013. №4(86) 234
Suppose that distribution functions are infinitely
differentiable and rapidly decreasing with all their
derivatives at infinity. Following the original idea of
Landau [3] and carrying on the Taylor expansion of
integrand in (3) (with respect to vv −' and ww −' ), we
obtain a formal series
( )
=1
( , ) = ( , ).k
ij i j ij i j
k
Q f f Q f f
∞
∑ (4)
The first term corresponds to the Landau collisional
integral (for arbitrary ),( μuijg in (3)):
3
2
(1) (1)( , ) = w ( ) ( )
2
1 1
( ) ( )
ij
ij i j ij
i R
i j
i j
m
Q f f d g u T
m v
f f
m v m w
αβ
α
β β
u
v w ,
∂
×
∂
∂ ∂
× −
∂ ∂
⎛ ⎞
⎜ ⎟⎜ ⎟
⎝ ⎠
∫
(5)
here the summation over repeated Greek indices
1,2,3=, βα is assumed,
2
1
(1)
1
= , ( ) = ,
( ) = 2 ( , )(1 ).
i j
ij
i j
ij ij
m m
m T u u u
m m
g u d g u
αβ αβ α βδ
π μ μ μ
u
−
−
+
−∫
(6)
The other terms of (4) can be symbolically written in
the form
3
( ) ( ) ( )
1
( )
1
( , ) = w ( ) ( , )
( ) = 2 ( , )(1 ) , 2,
k k k
ij i j ij ij
R
k k
ij ij
Q f f d g u A
g u d g u kπ μ μ μ
v w ,
−
− ≥
∫
∫
where ),()( wvk
ijA is a smooth integrable functions.
Then it becomes clear under which conditions the
system of Boltzmann equations (2) approximates (at the
formal level) the corresponding system of given Landau
equations, in which )(=)((1) ubug ijij , where )(ubij are
some given functions. It is formally sufficient to this
aim to choose the non-negative functions ),( μugij in
equations (2), (3) in the form );,( εμugij , where 0>ε
is a small parameter, and to demand that
1
0
1
1
0 1
2 ( , ; )(1 ) = ( ),
2 ( , ; )(1 ) = 0, 2.
ij ij
k
ij
d g u b u
d g u k
ε
ε
π μ μ ε μ
π μ μ ε μ
lim
lim
→
−
→
−
−
− ≥
∫
∫
(7)
As a simple example of such an approximation one
can consider functions
1
( , ; ) = 1 ( ) ,
2ij ijg u a uμ ε δ μ ε
πε
− −⎡ ⎤⎣ ⎦ (8)
where )(=)( ubua ijij , if 2( )ijb uε ≤ , otherwise
12ij ua ε( ) −= . The function ijg means that the
scattering always occurs at fixed angle
[ ])(1arccos uaijε− for collision of particles of sorts i
and j. This scattering law is convenient for the Monte
Carlo method. Another advantage of this approximation
is that the total collision frequency is constant:
1
1
1
( , ) = 2 ( , ; ) =tot
ij ijg u d g uε π μ μ ε
ε−
∫ . (9)
Such an approximation can be called quasi-
Maxwellian, since the total collision frequency (for any
pair of sorts i and j, including the case i = j) is
independent of velocities. Note that ε has dimensionality
3]][[ −lt , we ignore this fact considering ε simply as a
small parameter. From now on we consider the most
important case of Landau equations for the classical
plasma consisting of n sorts of charged particles with
charges }1,...,=,{ niei . Assuming the Coulomb
logarithm L is the same constant for all interactions, we
obtain (see, for example, [2]) equations (5) - (8), where
2 2
(1)
2 3( ) = ( ) = 4 ; , = 1, ..., .i j
ij ij
ij
e e
g u b u L i j n
m u
π (10)
It is clear that Boltzmann equations (2), (3), where
the functions );,( εμugij are computed by formulas
(7), (9), approximate (at least formally) as 0→ε the
system of Landau equations (4) for n -component
plasma. Note, that the formal error of above described
approximation of the Landau integral (1) ( , )i jQ f f by
the Boltzmann integral ),( ji ffQ has the first order
)(εO . More rigorous estimate gives the error not lager
than ( )O ε .
2. IMPLEMENTATION OF MONTE CARLO
METHOD FOR TWO COMPONENT
PLASMAS
The idea of the Monte Carlo method belongs to
G. Bird [1], who suggested it in 1960s, independently of
earlier works of M. Kac [12] on the probabilistic nature
of the Boltzmann equation. We choose as a basis the
approach of Kac. The idea is to associate nonlinear
equations (2) with some linear equation (Master
equation), describing relatively simple stochastic
process.
We consider in this section an example of electro-
neutral hydrogen plasma. The Landau equations have
the form (2) with collisional integral (5) and
2 2 2
1 2= 2, = =n e e e . We change indices 1 and 2 to e
(electrons) and i (ions), correspondingly, and denote
= , =e im m m M with = m Mγ . We perform a
normalization with units of 0ρ , the full density of
number of plasma particles; a characteristic velocity 0v
(for instance, the thermal electron velocity at the
equilibrium temperature 0T ); the electron-electron
collision time 0t : 4 2 3
0 0 02 / = 1Le t m vπ ρ . Equations (2),
(4) will be solved with initial conditions.
ISSN 1562-6016. ВАНТ. 2013. №4(86) 235
(0) (0)
(, , ,=0
3
= ), ( ) = 1.e i e i e it
R
f f d f∫v v v (11)
For the approximate solution of the problem we
choose a small real number > 0ε and a large integer
1N . We model the solution of this problem through the
evolution of the random vector
( ) ( ) ( ) ( ) 3
1 11 1
( ) = { ( ), ..., ( ); ( ), ..., ( )} ,e e i i N
N N Nt t t t t R∈V v v v v (12)
where 1= 2N N .
At = 0t all electron velocities ( ) (0)e
kv are
distributed in 3R independently in accordance with the
distribution function (0) ( )ef v and ion velocities ( ) (0)i
kv
are distributed in similar way with (0)
if , 1= 1, ...,k N .
Let us consider the scheme with the maximal time
step 1= , = 2 ,2N N NNτ ε then the time t takes
discrete values = , = 0,1, ...k Nt k kτ . Exactly one
collision happens at each interval 1[ , )k kt t + .
Probabilities of collisions of three possible kinds are
defined by = = , = .1 4 1 2ee ii eip p p After it is
decided, which of the three collisions, really happens,
we choose a random pair of velocities of particles of
corresponding sorts and "perform the collision". The
velocities after collision of two electrons and two ions
read
1
' = ( ),
2
1
' = ( ),
2
r
s
+ + −
+ − −
v v w | v w | ω
v v w | v w | ω
(13)
where the unit vector ω is defined in Cartesian
coordinates with the axis Oz along the vector
−u = v w in the following way:
{ }
{ } { }
2 2
2
3 3
= 1 cos , 1 sin , ,
4 4
= 1 2 ,1 , = 1 2 ,1 ,ee iiMin Min
u u
μ φ μ φ μ
ε εγ
μ μ
− −
− −
ω
where φ is a random angle distributed uniformly within
the interval [0, 2 )π . For the electron-ion collision we
choose velocities ( ) ( )
1= , = , 1 , ,e i
r s r s N≤ ≤v v v w
and transform them to
( )
( )
1
' = ( ),
1
' = ( ),
e
r
i
s
m M Mu
m M
m M mu
m M
+ +
+
+ −
+
v v w ω
v v w ω
(14)
where
{ }2
3
(1 )
= = 1 2 ,1 .ei Min
u
ε γ
μ μ
+
−
Thus, starting from the initial vector (0)NV , we
obtain a new vector ( )N NτV after the first collision.
After that the whole simulation process is repeated
many times and the time counter is increased at each
collision by the quantity Nτ .
We choose initial isotropic distributions
0 2
, = 1 / 2 ( 1), =| |, = ( , , ).e i x y zf v v v v vπδ − v v These
distributions mean that the initial thermal speeds of
electrons and ions are equal to one in our units. Note
that average velocities of the components are equal to
zero then 0 0= , =1 3 1 3e iT T γ . We compute some
moments
2 2
, ,
1
1
=1
1
( ) = ( ), = 1, 2, ...,n n
e i e i
N
k
v t v t n
N
〈 〉 ∑
and then make an average over K computational runs.
The resulting values for various values of parameters
are compared with practically exact values of integrals
2 2
,, ,
3
( ) = ( , ) = 1, 2, ...,n n
e i e i
R
v t d f t v n〈 〉 ∫ v v
obtained by using difference scheme from [5].
3. THE EFFECT OF INVERSE
BREMSSTRAHLUNG OF LASER
RADIATION
Let us consider the plasma dynamics in the high-
frequency weak electrical field ( ) = i tt e ω−E E , when
eiω ν and = eE Tev veE m ω (magnetic field
influence is neglectable). We suppose that Tev T l or
/Tev lω , where = 2T π ω , l is a characteristic
spacial scale, then
and ,
so ,
Tef v f
f f
l t
f f
t
ω
∂ ∂
∂ ∂
∂ ∂
∂ ∂
v
r
v
r
in this case the system of LFP equations reads
( ) ( )( ) = ( , ) ( , ),L Lk k k
ke k e ki k i
k
f e f
t Q f f Q f f
t m
∂ ∂
+ +
∂ ∂
E
v
= , .k e i
As it was shown in [13], that even for weak fields
E Tev v and 1Z , when Langdon parameter α is
big: 2 2= 1E TeZv vα , or, equivalently
2 2 2> >E T EZv v v the electron distribution function is far
from the Maxwellian one. It was shown in [14] for
arbitrary α , that the symmetrical part of an electron
distribution function (EDF) can be written in the
following form:
ISSN 1562-6016. ВАНТ. 2013. №4(86) 236
( )
0 3
0
( , ) = ,
4 ( ) ( )
( ) = (0) ,
e
Te Te
m
n v
f v t
v t v t
x exp x x
ϕ
π
ϕ ϕ −
⎛ ⎞
⎜ ⎟
⎝ ⎠
⎡ ⎤
⎣ ⎦
(15)
where
[ ]
[ ]
1/23/2
5/23/2
0.724
0
(5 ) 3 (3 )
(0) = , = ,
3 (3 ) (5 )
3
= 2 .
1 1.66 /
m m m
x
m m
m
ϕ
α
Γ Γ
Γ Γ
+
+
⎡ ⎤
⎢ ⎥⎣ ⎦
It can continuously vary from Maxwellian
( 2, 1m α= ) to a super-Gaussian form with 5m =
for 1α . Such nonequilibrium states can exist in a
plasma for 1α > because the inverse bremsstrahlung
heating rate is sufficiently fast for slow particles so that
electron-electron collisions cannot restore a Maxwellian
EDF. Also in [14] was obtained an equation for the time
evolution of the electron temperature
2
0 ( 0, ),
4
v
9
e
E
e
f v t
m
T ZY
t n
π
=
∂
=
∂
(16)
where 4 24 eY n e L mπ= . Equation (16) demonstrates
that the heating rate is entirely defined by behavior of
very slow electrons.
Now let us consider our particle simulation results.
First, we have calculated an electron heating rate. Fig. 1
shows an electron temperature normalized to its initial
value versus time for α=6.75 . We have also plotted in
Fig. 1 the heating rate which is predicted by Eq. (16)
with 0f given by (15) with 5m = (dashed line) and the
Maxwellian distribution 2m = (dotted line). As one
can expect the heating rate corresponds to the non-
Maxwellian EDF.
Fig. 1. Temporal dependence of the electron
temperature for DSMC method (solid line), the
distribution (15) (dashed line) and the Maxwellian
distribution (dotted line) for γ=1 1800 , N=2000,K=20,
-4=5 10 , Z=10,ε ⋅ α=6.75 , eiω=10ν
In Fig. 2 we plot the temporal dependence of the 6th
EDF moment for α=6.75 . The relativly small difference
between the DSMC method results and temporal
dependence expected for the distribution (15) is quite
understandable since, as it was mentioned in [14], the
laser energy absorbed by the fast electrons is much
smaller than energy absorbed by the slow electrons and
the EDF at high velocities (tail of distribution) should
remain close to the Maxwellian due to the e – e
collisions between fast and slow particles.
Fig. 2. Temporal dependence of the 6th electron
distribution function moment for DSMC method
(solid line), the distribution (15) (dashed line)
and the Maxwellian (dotted line).
The parameters are the same as in Fig. 1
Fig. 3. Temporal dependence of the 6th electron
distribution function moment for DSMC method (solid
line), the distribution (15) at m = 5 (dashed line) and
the Maxwellian (dotted line) for γ=1 1800 , N=2000,
,-4=5 10 , K=20 Z=3,ε ⋅ α=0.01 , eiω=10ν
The temporal dependence of the same 6th EDF
moment but for another α=0.01 is presented in Fig. 3. In
this case the EDF is Maxwellian one both for slow and
fast particles.
CONCLUSIONS
In conclusion, let us summarized the main results of
the paper. General approach to Monte Carlo methods
for Coulomb collisions is discussed. The approach is
based on a special quasi-Maxwellian way of approxima-
tion of the LFP equations by Boltzmann equations. The
DSMC numerical scheme is derived for the general case
of multicomponent plasmas. The order of approxima-
tion is not worse than ( )O ε , where ε is a parameter
of approximation being equivalent to the time step tΔ .
ISSN 1562-6016. ВАНТ. 2013. №4(86) 237
DSMC method is tested for the plasma dynamics in
the external high-frequency weak electrical field. The
numerical simulation confirmed that the non-
Maxwellian distribution function is composed of a su-
per-Gaussian bulk of slow electrons and a Maxwellian
tail of energetic particles. So there is a good agreement
between DSMC method results and the theory devel-
oped in Refs. [13, 14].
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Article received 01.04.2013.
СТОХАСТИЧЕСКОЕ МОДЕЛИРОВАНИЕ НЕЛИНЕЙНОГО КИНЕТИЧЕСКОГО УРАВНЕНИЯ
С ВЫСОКОЧАСТОТНЫМ ЭЛЕКТРОМАГНИТНЫМ ПОЛЕМ
А.В. Андрияш, А.В. Бобылев, А.В. Брантов, В.Ю. Быченков, С.А. Карпов, И.Ф. Потапенко
Предложен общий подход к моделированию кулоновских столкновений методом Монте-Карло. Основ-
ная идея заключается в аппроксимации системы уравнений Ландау-Фоккера-Планка (ЛФП) уравнениями
Больцмана квазимаксвелловского вида. Также рассматриваются высокочастотные поля, и приводится срав-
нение с полученными ранее результатами.
СТОХАСТИЧНЕ МОДЕЛЮВАННЯ НЕЛІНІЙНИХ КІНЕТИЧНИХ РІВНЯНЬ
С ВИСОКОЧАСТОТНИМ ЕЛЕКТРОМАГНІТНИМ ПОЛЕМ
А.В. Андрияш, А.В. Бобилєв, А.В. Брантов, В.Ю. Биченков, С.А. Карпов, І.Ф. Потапенко
Запропоновано загальний підхід до моделювання кулонівських зіткнень методом Монте-Карло. Основна
ідея полягає в апроксимації системи рівнянь Ландау-Фоккера-Планка (ОФП) рівняннями Больцмана квазі-
максвеллiвського виду. Також розглядаються високочастотні поля, і наводиться порівняння з отриманими
раніше результатами.
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