How to control NUM from UI

 

A first way of controlling the execution of SPIS/NUM solvers is through the source code. The object oriented (OO) language Java allows an easy handling of objects like a Spacecraft, a Plasma or a VolumeDistribution. In practice, this can be done either:

-        directly in the NUM Java source code as documented in Java for NUM.html (Java basics), NUM architecture.html (code architecture) and NUM integration in framework.html (practical file integration)

-        through the Jython command line of SPIS/UI (still to be documented).

 

The second simplified way of controlling the execution of SPIS/NUM is through a more classical user interface, offering the capability to modify parameters, either global or local. This is the subject of this page. Of course it reduces somewhat the range of possibilities with respect to what is really supported by the solvers. The advanced users may look at the source code of ..\API\public\spis\Top\Simulation\SimulationFromUIParams.html to see how most of the global parameters control the simulation at top level.

Note the last column of the tables below stating whether each property is in use or not as of this software version (currently 3.00.01rc1).

 

Global parameters are presented first, local parameters, i.e. fields living either in the volume or on a surface (spacecraft or external boundary), are presented next.

 

 

Global parameters

 

The general behaviour of NUM solvers is ruled by global parameters. They are organised by section:

-        Simulation control

-        Plasma

-        Poisson equation

-        B Field

-        Spacecraft

-        Particles sources on spacecraft

-        Interactions

-        Outputs

In each section the parameters are first reviewed, then listed in a table.

 

They can be edited through a spreadsheet editor, which is launched by the Solver/Set Global Param menu, or at first click on the UI to Num button.

 

Simulation control

The major parameters in use as of today’s version are simply the duration of the simulation and the time step for plasma dynamics integration.

If set to zero, the time step is automatically set so as to fulfil stability criteria. It roughly sets the time step so that particles do not cross more than a fraction of a cell in a time step (CFL-like condition), which also insures dt < 1/wp if the user defined cells smaller than Debye length. This is when electrons dynamics is modelled (PIC model), since things are much more stable when electrons are treated as a fluid (Boltzmann distribution only). Such automatic time step definition is quite difficult, hence this feature still lacks robustness. For example if particles are strongly accelerated after injection, time step can get too coarse and result in inaccuracies in trajectory integration. It does not take into account spacecraft potential evolution either (if floating) and it may lead to too fast potential evolution in case of small Csat and large current (e.g. when turning on a thruster). In all these cases return to a manual tuning of these parameter (plasmaDt, Csat…).

 

Name

Description

Variable type

Unit

Default value

In use

duration

Duration of the simulation

float

[s]

0.1

Yes

plasmaDt

Time step for plasma dynamics (automatic if = 0)

float

[s]

0.0

Yes

plasmaDuration

Duration of plasma dynamics inner loops (10 times plasmaDt if = 0)

float

[s]

0.0

little

scDt

Integration time for SC potential between each plasma dynamics loop integration (10 times plasmaDuration if = 0)

float

[s]

0.0

No

 

Plasma

This section defines the environment through two distributions of electrons and two of ions. The total should be neutral (not enforced).

The major point to be noted is that some of the parameters are names of classes. It means that Java generates a class from its name, which is possible thanks to the powerful introspection capabilities of Java. Reasonable defaults are provided for these classes, to which shy users can stick.

The general rules is for the environmentType parameter, which defined the environment:

-        this class must derive from the class Environment

-        have a specific constructor including the UI-defined parameters as described in ..\API\public\spis\Top\Plasma\Environment.html

-        in practice as of today only BiMaxwellianEnvironment is supported, which may involve two Maxwellians or only one by setting the second one(s) to zero density (as in the defaults)

The general rules for the ionDistrib* electronDistrib* parameters, which define the 4 particle populations (2 of ions, 2 electrons), is:

-        these class must derive from the class VolDistribWithIO

-        have a specific constructor including the UI-defined parameters as described in ..\API\public\spis\Vol\VolDistrib\VolDistribWithIO.html

-        in practice as of today only GlobalMaxwellBoltzmannVolDistrib and PICVolDistrib are supported. The latter described a particle population as a global thermal equilibrium distribution (Maxwell-Boltzmann) and is usually valid when no attractive potential or potential barrier exist. The Particle-In-Cell model (PICVolDistrib) really simulates this population dynamics but is much more costly in computation time and memory.

The supported types of ions is currently H+, O+, H20+, Xe+, Xe++, Ar+, Cs+, but can easily be increased (see the source of ..\API\public\spis\Top\Default\SpisDefaultPartTypes.html).

Name

Description

Variable type

Unit

Default value

In use

environmentType

Name of the Environment class  to be used (ex: BiMaxwellianEnvironment which will use the parameters below, or WorstCaseGeoEnvironment which will be self-contained)

String / Class

-

BiMaxwellianEnvironment

Yes

electronDensity

electron density (1st population)

float

[m-3]

1.0e6

Yes

electronTemperature

Electron temperature(1st population)

float

[eV]

1.0

Yes

electronDistrib

Name of the VolDistrib class to be used for electrons

String / Class

-

GlobalMaxwellBoltzmannVolDistrib

Yes

ionDensity

ion density (1st population)

float

[m-3]

1.0e6

Yes

ionTemperature

Ion temperature (1st population)

float

[eV]

1.0

Yes

ionVx

Ion drift velocity along x axis (1st population)

float

[m/s]

0.0

Yes

ionVy

Ion drift velocity along y axis (1st population)

float

[m/s]

0.0

Yes

ionVz

Ion drift velocity along z axis (1st population)

float

[m/s]

0.0

Yes

ionType

First ion population (a string that must be found in the particle types filename below)

String

-

H+

Yes

ionDistrib

Name of the VolDistrib class to be used for ions

String / Class

-

PICVolDistrib

Yes

electronDensity2

electron density (2nd population)

float

[m-3]

1.0e6

Yes

electronTemperature2

Electron temperature(2nd population)

float

[eV]

1000.0

Yes

electronDistrib2

Name of the VolDistrib class to be used for the 2nd electron population

String/ Class

-

GlobalMaxwellBoltzmannVolDistrib

Yes

ionDensity2

ion density (2nd population)

float

[m-3]

1.0e6

Yes

ionTemperature2

Ion temperature (2nd population)

float

[eV]

1000.0

Yes

ionVx2

Ion drift velocity along x axis (2nd population)

float

[m/s]

0.0

Yes

ionVy2

Ion drift velocity along y axis (2nd population)

float

[m/s]

0.0

Yes

ionVz2

Ion drift velocity along z axis (2nd population)

float

[m/s]

0.0

Yes

ionType2

Second ion population (a string that must be found in the particle types filename below)

String

-

H+

Yes

ionDistrib2

Name of the VolDistrib class to be used for ions 2nd population

String/ Class

-

PICVolDistrib

Yes

avPartNbPerCell

average number of super-particle per cell

NB: the average particle number per node is more relevant because computation  is mostly on the nodes. It is 6 times bigger, this is why avPartNbPerCell can be rather small ~ 5

float

[-]

5.0

Yes

 

Poisson equation

Poisson conditions are always:

-        Dirichlet on the spacecraft (fixed potential), the initial potential being defined in the local parameters (see next section)

-        Fourier on the external boundary (mixed Dirichlet-Neumann) with parameters defined so as to give an asymptotic behaviour in r-n

And are controlled by the poissonBCType parameter.

The non-linear Poisson solver includes one (or two) Maxwellian distribution directly in the Poisson solving scheme:

-Df = e(ni – n0 eef/kT) / e0

and has the major advantage to be stable even for cells larger than Debye length. If the non linear solver is selected (linearPoisson = 0), the electron distribution(s) are automatically inserted in the non-linear Poisson solver.

The next parameters, controlling the maximum iteration number or tolerance of the conjugate gradient Poisson equation solver, are rather for specialists.

Name

Description

Variable type

Unit

Default value

In use

poissonBCType

0-     Use the Poisson boundary conditions defined as fields through electric node editor (Dirchlet/Fourier with UI-defined parameters)

1-     Dirichlet on SC, Fourier on external boundary with alpha parameter mimicking a 1/r decay (~vacuum)

2-     Dirichlet on SC, Fourier on external boundary with alpha parameter mimicking a 1/r2 decay (~pre-sheath)

3-     Dirichlet on SC, Fourier on external boundary with alpha parameter mimicking a 1/rn decay, n being next parameter (poissonBCParameter1)

int

-

2

Yes

poissonBCParameter1

Parameter that can be used by some BC types (e.g. 1/rn exponent)

float

[varies]

 

Yes

poissonBCParameter2

2nd parameter that can be used by some BC types

float

[varies]

 

No

linearPoisson

0-     no: use non-linear Poisson solver

1-     yes: use linear Poisson solver

int

-

0

Yes

iterGradient

Maximum iteration number for conjugate gradient Poisson Solver

int

-

100

Yes

tolGradient

Tolerance for conjugate gradient Poisson Solver (stops when residue is smaller than tolGradient)

float

[-]

0.0001

Yes

iterGradientNl

Maximum iteration number for conjugate gradient Poisson Solver when non-linear solving

int

-

100

Yes

tolGradientNl

Tolerance for conjugate gradient Poisson Solver when non-linear solving

float

[-]

0.0001

Yes

iterNewton

Maximum iteration number for Newton algorithm in non-linear Poisson solving

int

-

10

Yes

tolNewton

Tolerance for Newton algorithm loop in non-linear Poisson solving

float

[-]

0.02

Yes

 

B field

An homogeneous B field can be defined this way.

Name

Description

Variable type

Unit

Default value

In use

Bx

x-component of the magnetic field (uniform over the computation box)

float

[T]

0.0

Yes

By

y-component of the magnetic field

float

[T]

0.0

Yes

Bz

z-component of the magnetic field

float

[T]

0.0

Yes

 

Spacecraft

If electricCircuitIntegrate = 0, spacecraft potentials are constant, if electricCircuitIntegrate = 1, the spacecraft floats, the relative capacitances being derived from material properties, whereas the spacecraft absolute capacitance is given by the parameter CSat.

Name

Description

Variable type

Unit

Default value

In use

electricCircuitIntegrate

Flag controlling SC electric circuit integration:

-        0: do not integrate (constant initial potentials)

-        1: integrate

int

-

1

Yes

initPotFlag

Flag to define initial spacecraft potential

-        0: set it to 0

-        1: uniform potential = initPot (next parameter)

-        2: local potential defined via the UI (SCDiriPot, see local parameters below)

int

-

1

Yes

initPot

Initial global potential for the spacecraft (if initPotFlag =1)

float

[V]

0

Yes

CSat

Spacecraft absolute capacitance

float

-

1.0e-9

Yes

electricCircuitFilename

Name of the file describing extra electric devices between electric (super-)nodes.

See below for syntax of circuit file.

The file must be in the "default input directory" (jython directory (!) on Windows XP, SpisUI on linux ??). (to be improved)

String

-

circuit.txt

Yes

 

 

Circuit file syntax

The file describing the electric circuit is composed of an arbitrary number of lines, each with the syntax:

componentDescriptor node1Id node2Id value

with:

- componentDescriptor (a string) one of

- C : it is a capacitor of capacitance value

- R : it is a resistor of resistance value

- V : it is a potential source of potential difference value (Vnode2 = Vnode1 + value)

- node1Id and node2Id (integers): the Ids of the (super) electric nodes between which to plug the component (same Id as in ElecNodeId)

- value (a float): the value of the component (resistance…)

Example file :

V 0 1 -10

R 0 2 1.e6

C 0 3 1.e-10

C 2 3 1.e-10

-        line 1: Electric super node 1 is biased of -10 V with respect to node 0, which is SC ground (it may be a Langmuir probe).

-        line 2: Electric super node 2 is related by a 1 MW resistor to SC ground (it may be a solar array).

-        line 3: Electric super node 3 is not related by any "real" component to SC ground, so it was chosen to model its capacitive coupling to the ground (this is not necessary, a fraction of SC absolute capacitance CSat is attributed to each electric node, proportionally to its area, so that it does not have zero capacitance, resulting in infinite potential as soon as it collects some charge).

-        line 4: the capacitive coupling between nodes 2 and 3 has been added (seldom useful).

 

 

Particle sources on spacecraft

These parameters allow the embedding of a plasma sources on the spacecraft (e.g. a thruster). Several sources are allowed, currently 4, but their number can easily be increased by modifying DefaultGlobalParam.py in SpisUI/DefaultValues folder.

Each source is controlled by the following three global parameters, which allow turning the source on, defining the source class and particle type. The general rules for the sourceType parameter, which defines the source class, is:

-        this class must derive from the class NonPicSurfDistrib

-        have a specific constructor including the UI-defined parameters as described in "Writing UI-supported classes" page and in ..\API\public\spis\Surf\SurfDistrib\NonPICSurfDistrib.html

-        in practice as of today only LocalMaxwellSurfDistrib and MaxwellianThruster are supported (the latter being experimental, but you can modify it, cf. ..\API\private\spis\Surf\SurfDistrib\MaxwellianThruster.html)

Extra local parameters allow to switch locally between the sources (sourceId), and to define their parameters (current, temperature, Mach number).

 

Name

Description

Variable type

Unit

Default value

In use

sourceFlag1

Flag for defining first artificial source on the spacecraft: 0 => none, 1 => yes, x => number of super-particles densified by x (for a local source, for which you want x times avPartNbPerCell particles per cell)

float

-

0

Yes

sourceType1

Name of the SurfDistrib class to be used for first artificial source on the spacecraft (ex: LocalMaxwellSurfDistrib, which will use the “source flux”, “source temperature” and “source Mach” user-defined local fields, whereas a specific EP model could only use the “source flux” and define internally its velocity distribution)

String / Class

-

LocalMaxwellSurfDistrib

Yes

sourceParticleType1

Type of particles for first particle source (a string that must be found in the particle types)

String

-

Xe+

Yes

sourceFlag2

Same as sourceFlag1, but for source 2

float

-

0

Yes

sourceType2

Same as sourceType1, but for source 2

String / Class

-

MaxwellianThruster

Yes

sourceParticleType2

Same as sourceParticleType1, but for source 2

String

-

electron

Yes

sourceFlag3

Same as sourceFlag1, but for source 3

float

-

0

Yes

sourceType3

Same as sourceType1, but for source 3

String / Class

-

LocalMaxwellSurfDistrib

Yes

sourceParticleType3

Same as sourceParticleType1, but for source 3

String

-

Cs+

Yes

sourceFlag4

Same as sourceFlag1, but for source 4

float

-

0

Yes

sourceType4

Same as sourceType1, but for source 4

String / Class

-

LocalMaxwellSurfDistrib

Yes

sourceParticleType4

Same as sourceParticleType1, but for source 4

String

-

In+

Yes

sourceNb

Number of particle sources: not to be modified in UI, but only in defaultGlobalParam.py if the number of sources is modified in defaultGlobalParam.py (e.g. if sourceNb is set to 5, sourceFlag5, sourceType5 and sourceParticleType5 must be defined in defaultGlobalParam.py located in SpisUI/DefaultValues folder).

int

-

4

Yes

 

 

Interactions

These parameters are mostly flags to turn interactions on or off.

Name

Description

Variable type

Unit

Default value

In use

photoEmission

-        if 0, no photo-emission

-        if 1, photo-emission is turned on with the sun direction defined below (no shading for now)

-        if 3, photo-emission is turned on with the sun direction defined below and photo-electron dynamics is modelled (PIC)

-        if 5, photo-emission is turned on with a sun flux defined locally (local parameters)

-        if 7, photo-emission is turned on with a sun flux defined locally (local parameters)and photo-electron dynamics is modelled (PIC)

NB: note each bit meaning: bit0=>on, bit1=>dynamics of photo-electrons is modelled, bit2=>local sun flux

int

-

0

Yes

electronSecondaryEmission

-        if 0, no secondary emission under electron impact

-        if 1, secondary emission under electron impact is turned on

-        if 2 or 3, secondary emission under electron impact is turned on and secondary electron dynamics is modelled

int

-

0

Yes

protonSecondaryEmission

-        if 0, no secondary emission under proton impact

-        if 1, secondary emission under proton impact is turned on

int

-

0

Yes

(under testing)

volumeConductivity

-        if 0, no volume conductivity

-        if 1, volume conductivity is turned on

int

-

0

Yes

inducedConductivity

-        if 0, no induced conductivity

-        if 1, induced conductivity is turned on

int

-

0

Yes

(under testing)

surfaceConductivity

-        if 0, no induced conductivity

-        if 1, induced conductivity is turned on

int

-

0

Yes

sunX

x-component of sun direction (points to sun, vector opposite to photons’ velocity)

float

-

0.0

Yes

SunY

y-component of sun direction

float

-

0.0

Yes

SunZ

z-component of sun direction

float

-

1.0

Yes

 

Outputs

These parameters mostly the periodicity for storing data for postprocessing (these data are then returned to UI and can be plotted).

Two last parameters tune the detail level for screen printing (or verbosity level).

Name

Description

Variable type

Unit

Default value

In use

scPotMonitorStep

time step for spacecraft ground potential monitoring (0.0 => none)

NB: used also for currents and potentials on each electric (super) node

float

[s]

0.0

Yes

scPotMapMonitorStep

time step for spacecraft local potential monitoring (0.0 => none)

float

[s]

0.0

Yes

scCurrentMapMonitorStep

time step for spacecraft local currents monitoring (0.0 => none)

float

[s]

0.0

Yes

plasmaPotMapMonitorStep

: time step for plasma potential monitoring (0.0 => none)

float

[s]

0.0

Yes

densitiesMapsMonitorStep

: time step for densities monitoring (0.0 => none)

float

[s]

0.0

Yes

particleTrajectoriesNb

number of particle trajectories per PIC population

int

-

0

No

materialPropertyPlots

plot material properties?

0=no, 1=yes

int

-

0

Yes

verbose

Verbosity level (level of screen messages about code execution):

0 = no print at all

1 = prints errors and warnings only

2 = 1 + minimal information

3 = 1 + more information (remains yet readable)

4 = even more information

… (next levels for debugging)

int

-

3

Yes

poissonVerbose

Same as verbose, but specific to Poisson solver

int

-

3

Yes

 

 

Local parameters

 

These local parameters are scalar fields living either in the volume or on a surface (spacecraft or external boundary). Not all of them are used in the present version of the code. Some come in addition to global parameters that they override when some flag declares that a property is to be considered as local (e.g. turning on an interaction only locally).

 

They can be defined through the group editor , which is launched by the Groups/Group editot menu or the Edit groups button. It allows to define them group by group (a uniform value on each group).

See the UI documentation for practical usage of the group editor. We simply edict the basic principles here:

-        in the CAD tool the user defines:

1.     spacecraft surface (physical) groups

2.     external boundary groups

3.     volume groups

-        in the group editor, for each of these 3 types of groups, a plasma must be defined:

1.     a plasma of type spacecraft for spacecraft surface groups

2.     a plasma of type boundary for boundary surface groups

3.     a plasma of type volume for volume groups

These 3 types of plasma must not be mixed (they involve flags telling the solvers what is the spacecraft or the boundary!). In each of the 3 categories you have a choice among a few predefined “plasmas”, and extra ones that you can modify. Trying to add new plasma through the UI is possible but difficult, prefer modification of the extra ones (adding a new one is easier in the source code, see SpisUI/Bin/MaterialMaker.py, where the default materials are defined).

-        for the spacecraft surface groups only, you MUST also choose a material and an electric node (even though the electric nodes are not yet used by the solvers, they must be defined). There again, you have a choice among a few predefined “materials” and “electric nodes”, and extra ones that you can modify (same thing about adding new ones).

 

The local fields are described now. They are grouped somewhat arbitrarily as Material, Electric Node, or Plasma properties. Affecting a given Material, Electric Node, and Plasma to a group affects their properties to each elements of the group.

NB: Only the properties that should be modified by the users are described here. You will find a few others in the Material, Electric Node, and Plasma editors (flags, xyz coordinates…) which should not be modified indeed.

 

Material properties

The major parameters are:

-        the material model Id, which can only be 0 for now, but may be different when other material models are developed (0, means NASCAP-like i.e. at least based on NASCAP material properties database

-        the material type Id is an Id which refers to the temporary default material list in SPIS, which is currently rather slim:

-        0: ITOC (Material coated with ITO)

-        1: CERS (Solar cell material. Cerium doped silicon with MgF2 coating)

-        2: CFRP (Carbon fibre, conducting, no resin layer)

-        3: Kapton

but can be extended easily (see the source code of ..\API\public\spis\Top\Default\SpisDefaultMaterials.html).

The predefined materials-plasma-electric_node that can be affected to each physical group are defined in SpisUI/Bin/MaterialMaker.py file, which can easily be modified (see SPIS/UI documentation on this topic, when available)

Name

Description

Unit

Default value

 

Live on (spacecraft, external boundary or volume):

Centring, or localisation (0=node, 1=edge, 2=surface, 3=volume)

In use

MatModelId

Id of the material model used for this material

-

0 (default model = NASCAP-properties-based)

SC

2

Yes

MatTypeId

Id of this material in its material model

-

-1 (no coating: bare metal, no interaction (except collection))

SC

2

Yes

MatThickness

Material thickness (if defined, overrides the default material thickness defined in the material properties)

[m]

-1 (use the default material thickness defined in the material properties)

SC

2

Yes

PhotoEmis

If 1, photo emission is turned on and simulated

-

0 (no photo emission)

SC

2

No

ElecSecEmis

If 1, secondary electron emission under electron impact is turned on and simulated

-

0 (no electron secondary emission)

SC

2

No

ProtSecEmis

If 1, secondary electron emission under proton impact is turned on and simulated

-

0 (no ion secondary emission)

SC

2

No

VolConduct

If 1, volume conductivity through the bulk material is turned on

-

0 (no volume conductivity)

SC

2

No

IndConduct

If 1, induced volume conductivity is turned on and simulated (if 0, the raw volume conductivity above is used)

-

0 (no induced conductivity)

SC

2

No

SurfConduct

If 1, surface conductivity is turned on and simulated (from the top of a cell to the next ones)

-

0 (no surface conductivity)

SC

2

No

Temperature

Surface temperature

[K]

300.0

SC

2

No

SunFlux

Sun flux on spacecraft

[sun at 1 AU]

-1.0 (compute it from sun direction, possibly including shades)

SC

2

Yes

 

 

Electric node properties

 

There is the only one property resulting of the choice of an electric node, its Id.

 

Name

Description

Unit

Default value

 

Live on (spacecraft, external boundary or volume):

Centring, or localisation (0=node, 1=edge, 2=surface, 3=volume)

In use

ElecNodeId

The electric (super) node this element is related to (SC ground, array ground…)

-

0 (default electric node, related to SC ground)

SC

2

Yes

 

 

Plasma properties

 

The next ones result of the choice of a plasma, which was commented in the introduction to this Local Parameters section. Only SCDiriPot, SourceCurrent, SourceTemp, and SourceMach are in use now.

 

Name

Description

Unit

Default value

 

Live on (spacecraft, external boundary or volume):

Centring, or localisation (0=node, 1=edge, 2=surface, 3=volume)

In use

surfThicknessS

Thickness of 2D surfaces (used when surfaces are tagged as thin, their thickness not meshed)

[m]

0.0

SC

2

Yes

edgeRadiusS

Radius of 1D elements (used when edges are tagged as physical thin wires, their thickness not meshed)

[m]

0.0

SC

1

Yes

SCDiriFlag

If 1, Dirichlet condition for Poisson equation on SC (fixed potential)

-

1 (yes)

SC

0

No:

set to 1, always Dirichlet on SC

SCDiriPotl

The potential to be used for Dirichlet condition

[V]

0.0

SC

0

Yes

SCFourFlag

If 1, Fourier condition for Poisson equation on SC: alpha pot + d(pot)/dn = value

-

0 (no)

SC

2

No:

set to 0, always Dirichlet on SC

SCFourApha

Alpha parameter in Fourier condition: alpha pot + d(pot)/dn = value

[m-1]

1.0

SC

2

No:

always Dirichlet on SC

SCFourValue

Right hand side parameter in Fourier condition : alpha pot + d(pot)/dn = value

NB: note the centring different from other Fourier parameters

[V]

0.0

SC

0

No:

always Dirichlet on SC

BdDiriFlag

If 1, Dirichlet condition for Poisson equation on external boundary (fixed potential)

-

0 (no)

Boundary

0

No: set to 0, always Fourier on boundary

BdDiriPot

The potential to be used for Dirichlet condition

[V]

0.0

Boundary

0

No:

always Fourier on boundary

BdFourFlag

If 1, Fourier condition for Poisson equation on external boundary

-

1 (yes)

Boundary

2

No: set to 1, always Fourier on boundary

BdFourAlpha

Alpha parameter in Fourier condition (used if poissonBCType = 0)

[m-1]

1.0 [m-1]

Boundary

2

Yes

BdFourVal

Right hand side parameter in Fourier condition (used if poissonBCType = 0)

[V]

0.0

Boundary

0

Yes

SourceId

Id of the local artificial plasma source defined on the spacecraft:

between 1 and sourceNb (=4) to have source 1 to 4 emitting at this place.

Value 0 or negative => no source.

NB: only one source can selected on each mesh element.

-

-1 (no source)

SC

2

No

SourceCurrent

Current of an artificial source defined on the spacecraft (NB: for some sources the unit can be different, e.g. the particle number, or the total current)

[A / m2]

0.0

SC

2

Yes

SourceTemp

Temperature of the emitted Maxwellian distribution, if sourceType of the corresponding sourceId (hence sourceType1 where sourceId = 1, or sourceType2 where sourceId = 2, etc.) is a LocalMaxwellSurfDistrib (if not, the interpretation of this value can be different)

[eV]

1.0

SC

2

Yes

SourceMach

Source Mach number (0 => Lambertian), if a LocalMaxwellSurfDistrib.(else different interpretation is possible)

[-]

0.0

SC

2

Yes

IncomPart

-        If 0, no particle are injected.

-        If 1, particles are injected (following the defined environment)

-

1 (injection)

Boundary

2

No

OutgoPart

-        If 0, outgoing particles are lost (sink)

-        If 1, they bounce specularly

(extra options possible)

-

0 (sink)

Boundary

2

No

VolInteracFlag

If 1, volume interaction is computed in that region (typically charge exchange)

-

0 (no)

Volume

3

No

BackgroundDens

Fixed background density used to compute volume interaction (typically: neutral density)

[m-3]

0.0

Volume

3

No