Problem Parameters

The problem definition is given by several parameters in the beginning,

[Format]

float

-

format version of the file

[Frequency]

float

Hz

frequency for harmonic problems

[Precision]

float

-

computing precision within FEMM

[MinAngle]

float

deg

angle restriction for the triangulation

[Depth]

float

lfac

typical length in z-direction

[LengthUnits]

string

-

unit used for lengths, e.g.

meters

centimeters

millimeters

inches

We will denote the unit by lfac in the following.

[Coordinates]

string

-

definition of the coordinate system

[ProblemType]

string

-

the 2D problem is either planar or axisymmetric

[extZo]

float

lfac

center of exterior (only if [ProblemType]is axisymmetric)

[extRo]

float

lfac

radius of exterior (only if [ProblemType] is axisymmetric)

[extRi]

float

lfac

radius radius of interior (only if [ProblemType] is axisymmetric)

[Comment]

string

-

problem description

Property Sections

Point Properties

This section defines boundary conditions on nodes,

[PointProps]

float

number of point subsections

<BeginPoint>

 

the beginning of a new point subsection

···

 

data of the subsection

<EndPoint>

 

marks the end of a point subsection


Each subsection contains between <BeginPoint> and <EndPoint>

<PointName>

string

-

property description

<A_re>

float

Wb/m

real component of the magnetic vector potential

<A_im>

float

Wb/m

imaginary component of the magnetic vector potential

<I_re>

float

A

real component of the current

<I_im>

float

A

imaginary component of the current

Boundary Properties

This section defines the boundary conditions on segments and arcsegments,

[BdryProps]

float

number of boundary subsections

<BeginBdry>

 

the beginning of a new boundary subsection

···

 

data of the subsection

<EndBdry>

 

marks the end of a boundary subsection

Each subsection contains between <BeginBdry> and <EndBdry>

<BdryName>

string

-

description of the property

<type>

int

-

the following values are possible

prescribed A

small skin depth

mixed

strategic dual image

periodic

anti-periodic

<Mussd>

float

-

relative permeability (for <type>= 2)

<Sigmassd>

float

MS/m

conductivity (for <type>= 2)

<c0>

float

-

real part of first coefficient (for <type>= 3)

<c0i>

float

-

imag. part of first coef. (for <type>= 3)

<c1>

float

-

real part of second coef. (for <type>= 3)

<c1i>

float

-

imag. part of second coef. (for <type>= 3)

<A_0>

float

Wb/m

magnetic vector potential on the segment (for

<type>= 1)

<A_1>

float

Wb/m

magnetic vector potential on the segment in xdirection (for <type>= 1)

<A_2>

float

Wb/m

magnetic vector potential on the segment in ydirection (for <type>= 1)

<Phi>

float

deg

angle (for <type>= 1)

Block Properties

This section defines the material properties,

[BlockProps]

float

number of block subsections

<BeginBlock>

 

the beginning of a new block subsection

···

 

data of the subsection

<EndBlock>

 

marks the end of a block subsection

Each subsection contains between <BeginBlock> and <EndBlock>

<BlockName>

string

-

description of the block

<Mu_x>

float

-

relative permeability in x-direction

<Mu_y>

float

-

relative permeability in y-direction

<H_c>

float

A/m

coercivity

<J_re>

float

MA/m2

real part of the source current density

<J_im>

float

MA/m2

imaginary part of the source current density

<Sigma>

float

MS/m

conductivity

<Phi_h>

float

deg

hysteresis lag angle for nonlinear problems

<Phi_hx>

float

deg

hysteresis lag angle in x-direction for linear problems

<Phi_hy>

float

deg

hysteresis lag angle in y-direction for linear problems

<BHPoints>

int

-

number of data points for interpolation

···

float array

-

<BHPoints>×2-array of data points (only if

<BHPoints> is greater than 0)

 

 

float

Tesla

Flux density of B-H curve data poind

 

 

float

A/m

Field intensity of B-H curve data point

<d_lam>

int

mm

lamination thickness

<LamFill>

float

-

fraction of the volume occupied per lamination

<NStrands>

int

-

number of strands

<WireD>

float

mm

diameter of each wire

<LamType>

int

-

possible values are

non-laminated or stranded (if <NStrands> is set) or laminated in plane (if <d lam> and <LamFill> are set)

lamination parallel to x (planar) or r (axisymmetric)

lamination parallel to y (planar) or z (axisymmetric)

magnet wire

plain stranded wire

litz wire

square wire

Circuit Properties

This section defines the block material properties of circuits,

[CircuitProps]

float

number of circuits subsections

<BeginCircuit>

 

the beginning of a new circuits subsection

···

 

data of the subsection

<EndCircuit>

 

marks the end of a circuits subsection


Each subsection contains between <BeginCircuit> and <EndCircuit>

<CircuitName>

string

-

description of the block

<type>

int

-

possible values are

parallel

series

<TotalAmpsre>

float

A

real part of the circuit current

<TotalAmpsim>

float

A

imaginary part of the circuit current

Points

This section defines the points,

[NumPoints]

int

Number of points

 

array

<NumPoints> x 4 array of points. Each row corresponds to a point and it contains the following columns

 

float

lfac

x-position of the point or r (axisymmetric)

 

float

lfac

y-position of the point or z (axisymmetric)

 

int

-

number of associated node property. 0 indicates no associated property; 1 or above indexes the associated nodal property

 

int

-

number of group

Segments

This section defines segments.

[NumSegments]

int

number of segments

···

array

<NumSegments>×6-array of segments. Each row corresponds to a segment and it contains the following columns

int

-

the number of the start point

 

int

-

the number of the end point

 

float

-

the mesh size factor (-1 means auto)

 

int

-

the number of boundary property

 

int

-

hide in postprocessor (0 for no, 1 for yes)

 

int

-

number of group

ArcSegments

This section defines arcsegments,

[NumArcSegments]

int

number of arcsegments

···

array

<NumSegments>×7-array of arcsegments. Each row corresponds to a arcsegments and it contains the following columns

int

-

the number of the start point

 

int

-

the number of the end point

 

float

deg

arc angle (1 to 180 deg)

 

float

deg

max segment (0.01 to 10)

 

int

-

the number of boundary property

 

int

-

hide in postprocessor (0 for no, 1 for yes)

 

int

-

number of group

Holes

This section defines non-meshed holes in the solution domain

[NumHoles]

int

number of holes

···

array

<NumHoles>×3-array of info on each hole. Each row corresponds to hole and it contains the following columns

float

lfac

x-position of the BlockLabel or r (axisymmetric)

float

lfac

y-position of the BlockLabel or z (axisymmetric)

int

--

Number of group associated with the hole

Block Labels

This section defines block labels,

[NumBlockLabels]

int

number of block labels

···

array

<NumBlockLabels>×9-array of block labels. Each row corresponds to a block label and it contains the following columns

float

lfac

x-position of the BlockLabel or r (axisymmetric)

 

float

lfac

y-position of the BlockLabel or z (axisymmetric)

 

int

-

number of block type (region)

 

float

-

desired mesh size

 

int

-

number of the associated circuit (first circuit number is 1; 0 indicates no associated circuit)

 

float

deg

Magnetization direction

 

int

-

number of group

 

int

-

number turns (for stranded conductor coupling); 1 if not a stranded conductor

 

int

-

Flag where a value of 1 denotes that block label located in external region (for axisymmetric Kelvin Transformation boundary conditions); otherwise zero.


Adapted from Sebastian Schoeps, “FEMMview File Format”, 2009-06-09

https://bitbucket.org/schoeps/fides/downloads/FEMMview.pdf