Modeling of spacecraft interaction with environment
At ITM (NASU and NSAU) investigations of various aspects, processes and phenomena related to spacecraft environment interactions are carried out in plasma electrodynamic facilities. The results presented illustrate the efficiency of physical modeling to solve the problems formulated. В ИТМ НАНУ и НК...
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Інститут технічної механіки НАН України і НКА України
2008
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| Cite this: | Modeling of spacecraft interaction with environment / V.A. Shuvalov, A.I. Priimak // Техн. механика. — 2008. — № 2. — С. 26 – 33. — Бібліогр.: 6 назв. — англ. |
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| author | Shuvalov, V.A. Priimak, A.I. |
| author_facet | Shuvalov, V.A. Priimak, A.I. |
| citation_txt | Modeling of spacecraft interaction with environment / V.A. Shuvalov, A.I. Priimak // Техн. механика. — 2008. — № 2. — С. 26 – 33. — Бібліогр.: 6 назв. — англ. |
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| description | At ITM (NASU and NSAU) investigations of various aspects, processes and phenomena related to spacecraft environment interactions are carried out in plasma electrodynamic facilities. The results presented illustrate the efficiency of physical modeling to solve the problems formulated.
В ИТМ НАНУ и НКАУ на плазмодинамическом стенде проводятся исследования различных процессов и явлений, характеризующих взаимодействие КА с околоспутниковой средой. Представленные результаты демонстрируют эффективность физического моделирования для решения поставленных задач.
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| first_indexed | 2025-12-07T17:32:23Z |
| format | Article |
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26
UDC 533.95
V.A. SHUVALOV, A.I. PRIIMAK
MODELING OF SPACECRAFT INTERACTION WITH ENVIRONMENT
At ITM (NASU&NSAU) investigations of various aspects, processes and phenomena related to spacecraft
environment interactions are carried out in plasma electrodynamic facilities. The results presented illustrate the
efficiency of physical modeling to solve the problems formulated.
В ИТМ НАНУ и НКАУ на плазмодинамическом стенде проводятся исследования различных про-
цессов и явлений, характеризующих взаимодействие КА с околоспутниковой средой. Представленные
результаты демонстрируют эффективность физического моделирования для решения поставленных задач.
Active life and service life of spacecraft (SC) and their subsystems are de-
pendent on the accuracy of prediction of variations in structural material and ele-
ment properties under a long action of factors of space and the environment. De-
spite great experience related to operating spacecraft in various orbits, prediction
of their service life remains a non-trivial problem. The complexity and high cost of
full-scale experiments give no way of considering it as an acceptable means to
study in details individual types of spacecraft-environment interactions, and it is
impossible to identify their contributions in integral characteristics of the action on
spacecraft. Thus to build models of interactions, to predict the consequences of a
long action of space factors on structural materials and elements, physical model-
ing plays a special role.
Degradation of solar arrays power. Basic factors of influence of the envi-
ronment on high-orbiting spacecraft are as follows: ionizing radiation, thermal cy-
cling in a vacuum, radiation electrization, plasma jets of electric propulsion en-
gines (EPE) of spacecraft, destruction, sublimation, and gassing of materials and
coatings, contamination of operated systems surfaces and solar ultraviolet (UV)
emission [1].
For simulating the long impact of ionizing radiation, when degradation of
spacecraft materials and the solar array (SA) power losses are predicted, the equal-
ity of equivalent fluences of electrons for particles solar arrays penetrating through
the protective coating on the photovoltaic converters is the basic condition:
)()( H
e
M
e FF = (the indices M and H correspond to simulation and orbit, respec-
tively).
The equality of the number N and amplitude minmax TTT −=∆ of thermal
cycles in orbit and on the test bench is the condition of equivalence of thermal-
cycling impacts: HMHM TTNN ∆=∆= , .
The equality of fluences
)()( H
eh
M
eh FF = and energies
)()( H
eh
M
eh WW = of ener-
getic electrons in orbit and on a test bench is the condition of modeling radiation
electrization of SC structural materials and elements: 203 ≤≤ ehW keV [2].
The equality of specific charges ( HM qq = ) and energies ( iHiM WW = ) of
uniform ions transferred by an electric propulsion jet onto the SA surface is the
condition of modeling the interaction of electric propulsion plasma jets with SA
and SC external surface materials in orbit and on the test bench.
The equality of values and dependences of the integral coefficient of absorp-
tion of the solar radiation )()()(
tH
s
M
s α=α is the condition of successful numeri-
cal simulation and physical modeling of the influence of contamination of solar
V.A. Shuvalov, A.I. Priimak, 2008
Техн. механика. – 2008. – № 2.
27
arrays protective glasses ( t is the SC operation time, duration of the effects of the
environment).
Changed electric power of SA is a result of an integrated action of many fac-
tors of the near-satellite environment in SC operation in orbit. The integral charac-
teristic of the SA rated power drop ( ) 0PtP is approximated by the relation [3]
( 0P is the SA power initial value)
( ) ( )
∑
=
−=
n
i
i
i
P
tP
k
P
tP
1 00
1 , (1)
where ik is the coefficient of proportionality which takes into account the influ-
ence of separate factors and the effects of overlapping, and n is the number of
factors, ( )tPi – electric power degradation due to factor i alone, ( )tP – value of
electric power at the time t. The value of the coefficient 10 ≤≤ ik and the number
of n – factors are determined by contribution of each factor for a particular space-
craft.
If conditions of modeling are fullfilled in testing the influence individual fac-
tors on fragments SA silicon solar arrays, it will be derived calculated and experi-
mental dependences of the SA power drop on the time of operation of GEO
spacecraft and Global Position System (GPS) high-orbiting spacecraft constella-
tion by using the relation (1). Fig.1 shows the calculated and experimental depend-
ence ( ) 0PtP which characterizes an integral action of the near-satellite environ-
ment in geostationary orbit (GEO). The measured values of ( ) 0PtP correspond
to SA with the silicon conductivity of 10
2
ohm
-1
m
-1
and the thickness of the pro-
tecting glass (fused quartz) of 0.3 mm. On Fig. 1 it was used the following indica-
tions: 1 – is the relation (1); satellite measurements: 2 – Intelsat-IV, 3 – Western
Union F1, F2, 4 – Telesat Anik F1, F2, 5 – Tacsat, 6 – averaged data in GEO, 7 –
ATS-5, 8 – IDSDS, 9 – LES-6.
Fig. 1
The data of Fig. 2 for GPS satellites in a high circular orbit also confirm the
correctness of the procedure of estimating the influence of integral actions of the
28
environment factors on SA with the use of the relationship (1) and of numerical
and experimental dependences ( ) 0PtPi characterized by the influence of separate
factors. On Fig. 2 it was used the following indications: 1 – integral effects of ion-
izing radiation, contramination and thermocycling (1); satellite measurements: 2 –
GPS SC 13-17 block II, 3 – SC 18-21 block II, 4 – SC 22-40 block II, 5 – SC 1-6
block I.
Radiation electrization of spacecraft leeward surfaces. Spacecraft radiation
electrization in a polar ionosphere in the Earth’s shadow results from two effects
of the environment: irradiation by fast auroral electrons with energies from 1 to
35 keV (captured in radiation belts of the Earth) and the flow of a cold ionospheric
plasma. If the concentration of positive ions near the SA body surface is
≤iWN 10
4
сm
-3
, negative charges up to a voltage of 1 kV are accumulated on di-
electric surfaces [1]. The effects and consequences of high-voltage differential
charging are the most hazardous for the leeward surfaces of extended structural
elements of electrodynamically large satellites ( ≥λdR 10
2
) and also for small
bodies in the nearbody wake (R is the characteristic size of a spacecraft,
eed NekT 24π=λ is the Debye screening length of the undisturbed plasma, k
is the Boltzmann constant, e is the electron charge, ee NT , are the temperature
and the concentration of electrons in a cold plasma).
Fig. 2
Numerical simulation of high-voltage charging the SC surfaces in a polar
plasma in the Earth’s shadow involves a non-trivial problem of the joint solution
of nonlinear Vlasov–Poisson equations for a predetermined condition of the flow
around a dielectric body and current-balance equations on the irradiated surface.
The values of the coefficients of interactions between the charged particles and the
surface for a particular material are determined experimentally.
Physical modeling high-voltage charging in a polar ionosphere is concerned
with the necessity of reproducing the current density distribution in the near-body
wake, conditions of the flow around body in a supersonic cold plasma under simul-
taneous irradiation of streamlined surfaces by fast electrons with energies from 1
to 35 keV. The difficulties of such studies are caused by the necessity of simulta-
neous implementation of conditions of plasma gasdynamic and electrophysical
modeling [4, 5].
29
Physical modeling radiation electrization in the near-spacecraft wake in a po-
lar orbit amounts to reproducing full-scale values of the range of energy and cur-
rent density of auroral electrons, an ionic current and the current of secondary ion-
electron emission in facilities (by using samples of structural elements from dielec-
tric materials and coatings). These conditions are realized in plasma dynamic fa-
cilities at the ITM in supersonic flows of the rarefied n++ +
2O plasma with the
concentration ∞iN =1.6× 10
5
– 5.7× 10
7
cm
-3
of charged particles and velocity
≈∞U 8.4 и 11.9 km/s. The reference models are made from an isolated aluminum
plate with one side covered by a dielectric and a disk made of fused quartz with
one side covered by an aluminum film.
Fig. 3 shows the equilibrium potential eWW kTeϕ=Φ ( Wϕ is the surface
potential) on the leeward side of the solid as a function of concentrations of fast
electrons and positive ions iWeh NN / . Satellite measurements with F6, F7, and
F13 (Defense Meteorological Satellite Program) are made in a polar orbit in the
Earth’s shadow while acting fast electrons with energies ≈ehW 4.2; 10.1;
14.4 keV. On Fig. 3 it was used the following indications: 1, 2, 3 – measurements
by DMSF-series F6, F7, F13 satellites; 4 – calculated values; measurements with
samples (ITM): 5 – A1; 6 – carbonic plastic material; 7 – the TR-SO-11 coating; 8
– 12X18H10T stainless steel.
Fig. 3
The dependences WΦ on iWeh NN make it possible to predict the levels of
charging the leeward surfaces of spacecraft structural elements and small bodies in
their wake in a polar ionosphere in the Earth’s night shadow.
Variations in spacecraft material properties under a long action of atomic
oxygen. The problem of maintaining a prolonged operation of spacecraft in low
and mean (200 – 700 km) orbits is closely connected with the problem of provid-
ing the durability of materials and coatings of external surfaces of structural ele-
ments to the action of atomic oxygen (AO).
The mechanism of failure of materials of spacecraft external surfaces includes
at least two types of the influence: physical spluttering and chemical etching by a
flux of atomic oxygen. The consequences of the AO influence on materials of
spacecraft solar arrays are as follows:
30
– mass loss from the surface of materials;
– variations in thermo-optical properties of material surfaces (the integral co-
efficient of absorption of solar radiation, sα , and integral emissivity, ε );
– reduction of electric conductivity of metal-to-metal contacts due to their
oxidation;
– variations in physical and mechanical properties of materials as a results of
their surface erosion.
Information about variations in the properties of materials of spacecraft exter-
nal surfaces due to the action of the atomic oxygen flux may be only derived by
the experiment: from the results of in-flight or benchmark tests. The equality of
velocities and energies for identical types of the particles bombarding the surface
is the condition of bench (physical and chemical) modeling and simulation of the
action of the AO flux on the spacecraft external surfaces in orbit.
The fulfillment of the conditions of modeling in the collisionless flow around
the surfaces of a solid body with a supersonic flux of partially ionized AO one can
ensure modeling and simulation of the processes of physical (dynamic) and chemi-
cal interactions of the materials of external surfaces with AO in the Earth’s iono-
sphere. Simulation of the conditions of a prolonged operation of a spacecraft in
orbit suggests the performance of accelerated tests by using more intensive particle
fluxes than in orbit.
Thus, in order to realize accelerated model tests of materials for external sur-
faces of spacecraft with the aim of determining their erosion resistance to the in-
fluence of atomic oxygen in the ionosphere, one needs to provide for:
– the flux of partially ionized AO with directional velocities of particles which
are close or equal to orbital velocities in the ionosphere;
– the condition of the collisionless gas flow around the fragments of space-
craft structural elements or the samples of materials under test.
The conditions listed above are realized in plasma dynamical facilities of the
ITM. Schematic of facilities is shown on Fig. 4 [7]. On Fig. 4 it was used the fol-
lowing indications: 1 – vacuum chamber, 2 – pumping-out system, 3 – generator of
supersonic plasma current, 4 – sample (SC model), 5, 6 – diagnostic systems, 7 –
cryogenic panels (LN2), 8 – electron gun, 9, 11 – microwave systems aerials, 10 –
source of ultraviolet radiation.
Fig. 4
Samples of tested materials (four ones, simultaneously) are mounted on a
frontal (relative to a free-stream flow) surface of a two-section thermostat cooled
31
by the running water and liquid nitrogen. The thermostat of 115×115 mm in di-
mensions is arranged on a movable platform of a lower coordinate-measuring
gage.
Investigations in kinetics of the process of interaction of atomic-molecular
oxygen plasma, for example, with a polyimide film testify that molecular oxygen is
inert and takes no part in chemical reactions. All chemical reactions are limited by
one stage: reaction with oxidizer (atomic oxygen). In this case, the velocity rela-
tion of gas release for products of chemical etching (СО2, СО, Н2О and Н2) re-
mains constant.
Fig. 5 presents the dependence of variations in the polyimide film thickness
x∆ ( 0x =0.040 mm) on the integral fluence of atomic oxygen OF . On Fig. 5 it
was used the following indications: 1 – ITM’s measurements at AO flux velocity
of (8.3±0.5) km/s, 2 – irradiation of the PM-A film by diffusely scattered particles
with thermal velocities of 2.24 km/s, 3 – Mir Orbital Station (the PM-1E film,
δ ≈ 0.040 mm, exposure time Ht = 28 and 42 months), 4 – dependence
x
Oe FRx
β⋅=∆ ( 1.0≈βx , 24102.6 −⋅≈eR cm
3
/Oatom). The dependence
x
Oe FRx
β⋅=∆ ( eR is the volume coefficient of material losses, xβ is the coeffi-
cient), presented in Fig. 5, points to the fact that the mechanism of chemical etch-
ing the atomic oxygen film has the overwhelming influence. Losses in mass of the
PM-A polyimide film, owing to the action of the atomic oxygen flux, is illustrated
by Fig. 6. On Fig. 6 it was used the following indications: 1 – ITM measurements,
2 – Mir OS (the PM-1E film, 0.040≈0x mm), 3 – Mir OS (the PM-1E film, Ht =
28 and 42 months), 4 – Mir OS (the PM-1E film, 0.080≈0x mm, Ht =
1036 days), 5 – HF-plasma, 6 – dependence m
O
FYm
β⋅=∆ 0 (for the PM-A film
1.0≈βm , 24104.2 −⋅≈0Y mg/Oatom).
An increase of the diffuse component of emission (the degree of roughness of
the film) is the result of the atomic oxygen impact on the surface of exposed sam-
ples. A slight however stably recorded increase of emitting capability of materials
in the infrared range ε is a consequence of such changes. The integral coefficient
of solar radiation absorption in a visible part of a spectral range of wave lengths
increases. Data of Fig. 7 provide support for this. On Fig. 7 it was used the follow-
ing indications: 1 – ITM, 2 – Mir OS (1036 days, the film thickless is 0.08 mm), 3
– satellite averaged measurements, 4 – approximation 31.27.5101 Os F⋅⋅=α∆ − .
The values of ε measured in an atomic-molecular oxygen flux at various flu-
ences of atomic oxygen in ITM’s facilities are presented in Table 1.
Table 1 – Infrared emissing ability of the PM-A film
Emissivity coefficient ε
OF , сm
-2
Before exposure in flux After exposure in flux
1.16⋅10
20
3.67⋅10
20
4.9⋅10
20
1.27⋅10
21
0.550
0.550
0.550
0.550
0.550
0.560
0.560
-
*)
Note: * The sample is failured, the failure time is equivalent to ≈Ht 3.8
years in orbit with ≈h 700 km under conditions of maximal solar
activity.
32
Fig. 5
Fig. 6
33
Fig. 7
The relations ( )OFm and ( )OFx can be used for predicting service life, ma-
terial resistance to long attack by atomic oxygen in orbit, for estimating and con-
trolling atomic oxygen fluence.
The results presented demonstrate the validity of physical modeling for pre-
dicting variations in surface properties of structural materials and elements be-
cause of a long-term action of various factors of the near-satellite environment.
1. Power Losses of Solar Arrays under the Action of an Environment in a Geosynchronous Orbit / V. A. Shuvalov,
G. S. Kochubey, V. V. Gubin, N. A. Tokmak // Cosmic Research. – 2005. – Vol. 43, № 4. – P. 259 – 267.
2. Shuvalov V. A. Radiation Electrization of Spacecraft Construction Elements: Physical Modeling of Charge
Accumulation and Neutralization / V. A. Shuvalov, A. I. Priimak, V. V. Gubin // Cosmic Research – 2001. –
Vol. 39, № 1. – P. 18 – 22.
3. G. S. Kochubey. Losses in High-Orbiting Spacecraft Solar Arrays Power under Long Impact of Gus/Plasma
Flows and Irradiation in Orbit / G. S. Kochubey // Tekhnicheskaya Mekhanika – 2004. – № 2. – P. 64 – 71.
4. Radiation Electrization of Spacecraft Leeward Surfaces by Auroral Electrons in The Ionosphere /
V. A. Shuvalov, G. S. Kochubey, A. I. Priimak, V. V. Gubin, N. A. Tokmak // Cosmic Research. – 2003. –
Vol. 41, № 4. – P. 413 – 423.
5. Charge Transfer by High-Energy Electrons onto the Leeward Surfaces of a Solid in a Supersonic Rarefied
Plasma Flow / V. A. Shuvalov, A. I. Priimak, K. A. Bandel, G. S. Kochubey // Journal of Applied Mechanics
and Technical Physics. – 2008. – Vol. 49, № 1. – P. 9 – 17.
6. Changes of Properties of the Materials of Spacecraft Solar Arrays under the Action of Atomic Oxygen /
V. A. Shuvalov, G. S. Kochubey, A. I. Priimak, N. I. Pis’mennyi, N. A. Tokmak// Cosmic Research. – 2007. –
Vol. 45, № 4. – P. 294 – 304.
Institute of Technical Mechanics Received 26.08.08,
of the National Academy of Sciences of Ukraine in final form 22.09.08
and the National Space Agency of Ukraine
Dnepropetrovsk
|
| id | nasplib_isofts_kiev_ua-123456789-5567 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1561-9184 |
| language | English |
| last_indexed | 2025-12-07T17:32:23Z |
| publishDate | 2008 |
| publisher | Інститут технічної механіки НАН України і НКА України |
| record_format | dspace |
| spelling | Shuvalov, V.A. Priimak, A.I. 2010-01-26T15:10:20Z 2010-01-26T15:10:20Z 2008 Modeling of spacecraft interaction with environment / V.A. Shuvalov, A.I. Priimak // Техн. механика. — 2008. — № 2. — С. 26 – 33. — Бібліогр.: 6 назв. — англ. 1561-9184 https://nasplib.isofts.kiev.ua/handle/123456789/5567 533.95 At ITM (NASU and NSAU) investigations of various aspects, processes and phenomena related to spacecraft environment interactions are carried out in plasma electrodynamic facilities. The results presented illustrate the efficiency of physical modeling to solve the problems formulated. В ИТМ НАНУ и НКАУ на плазмодинамическом стенде проводятся исследования различных процессов и явлений, характеризующих взаимодействие КА с околоспутниковой средой. Представленные результаты демонстрируют эффективность физического моделирования для решения поставленных задач. en Інститут технічної механіки НАН України і НКА України Modeling of spacecraft interaction with environment Article published earlier |
| spellingShingle | Modeling of spacecraft interaction with environment Shuvalov, V.A. Priimak, A.I. |
| title | Modeling of spacecraft interaction with environment |
| title_full | Modeling of spacecraft interaction with environment |
| title_fullStr | Modeling of spacecraft interaction with environment |
| title_full_unstemmed | Modeling of spacecraft interaction with environment |
| title_short | Modeling of spacecraft interaction with environment |
| title_sort | modeling of spacecraft interaction with environment |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/5567 |
| work_keys_str_mv | AT shuvalovva modelingofspacecraftinteractionwithenvironment AT priimakai modelingofspacecraftinteractionwithenvironment |