properties Module

All ungrouped properties are defined in this file. This includes:

• PFAST

• PGAP

• PRAC2D (CrackProperty)

• PRAC3D (CrackProperty)

• PCONEAX (not done)

class pyNastran.bdf.cards.properties.properties.CrackProperty

Bases: pyNastran.bdf.cards.base_card.Property

dummy init

Mid() → int

returns the material ID of an element

Returns

midint

the Material ID

write_card(size: int = 8, is_double: bool = False) → str

Writes the card with the specified width and precision

Parameters

sizeint (default=8)

size of the field; {8, 16}

is_doublebool (default=False)

is this card double precision

Returns

msgstr

the string representation of the card

class pyNastran.bdf.cards.properties.properties.PFAST(pid, d, kt1, kt2, kt3, mcid=-1, mflag=0, kr1=0.0, kr2=0.0, kr3=0.0, mass=0.0, ge=0.0, comment='')

Bases: pyNastran.bdf.cards.base_card.Property

1	2	3	4	5	6	7	8	9
PFAST	PID	D	MCID	MFLAG	KT1	KT2	KT3	KR1
	KR2	KR3	MASS	GE
PFAST	7	1.1	70

Creates a PFAST card

Parameters

pidint

property id

dfloat

diameter of the fastener

kt1, kt2, kt3float

stiffness values in directions 1-3

mcidint; default=01

specifies the element stiffness coordinate system

mflagint; default=0

0-absolute; 1-relative

kr1, kr2, kr3float; default=0.0

rotational stiffness values in directions 1-3

massfloat; default=0.0

lumped mass of the fastener

gefloat; default=0.0

structural damping

commentstr; default=’’

a comment for the card

Mass()

Mcid()

classmethod _init_from_empty()

classmethod add_card(card, comment='')

Adds a PFAST card from BDF.add_card(...)

Parameters

cardBDFCard()

a BDFCard object

commentstr; default=’’

a comment for the card

cross_reference(model: BDF) → None

Cross links the card so referenced cards can be extracted directly

Parameters

modelBDF()

the BDF object

d = None

diameter of the fastener

ge = None

Structural damping

kr1 = None

Rotational stiffness values in directions 1-3

kt1 = None

stiffness values in directions 1-3

mass = None

Lumped mass of fastener

mcid = None

Specifies the element stiffness coordinate system

mflag = None

0-absolute 1-relative

pid = None

Property ID

pname_fid_map = {'KR1': 'kr1', 'KR2': 'kr2', 'KR3': 'kr3', 'KT1': 'kt1', 'KT2': 'kt2', 'KT3': 'kt3', 'MASS': 'mass'}

raw_fields()

repr_fields()

Gets the fields in their simplified form

Returns

fieldsList[varies]

the fields that define the card

type = 'PFAST'

uncross_reference() → None

Removes cross-reference links

write_card(size: int = 8, is_double: bool = False) → str

Writes the card with the specified width and precision

Parameters

sizeint (default=8)

size of the field; {8, 16}

is_doublebool (default=False)

is this card double precision

Returns

msgstr

the string representation of the card

class pyNastran.bdf.cards.properties.properties.PGAP(pid, u0=0.0, f0=0.0, ka=100000000.0, kb=None, mu1=0.0, kt=None, mu2=None, tmax=0.0, mar=100.0, trmin=0.001, comment='')

Bases: pyNastran.bdf.cards.base_card.Property

1	2	3	4	5	6	7	8	9
PGAP	PID	U0	F0	KA	KB	KT	MU1	MU2
	TMAX	MAR	TRMIN
PGAP	2	0.025	2.5	1.E6		1.E6	0.25	0.25

Defines the properties of the gap element (CGAP entry).

Parameters

pidint

property id for a CGAP

u0float; default=0.

Initial gap opening

f0float; default=0.

Preload

kafloat; default=1.e8

Axial stiffness for the closed gap

kbfloat; default=None -> 1e-14 * ka

Axial stiffness for the open gap

mu1float; default=0.

Coefficient of static friction for the adaptive gap element or coefficient of friction in the y transverse direction for the nonadaptive gap element

ktfloat; default=None -> mu1*ka

Transverse stiffness when the gap is closed

mu2float; default=None -> mu1

Coefficient of kinetic friction for the adaptive gap element or coefficient of friction in the z transverse direction for the nonadaptive gap element

tmaxfloat; default=0.

Maximum allowable penetration used in the adjustment of penalty values. The positive value activates the penalty value adjustment

marfloat; default=100.

Maximum allowable adjustment ratio for adaptive penalty values KA and KT

trminfloat; default=0.001

Fraction of TMAX defining the lower bound for the allowable penetration

commentstr; default=’’

a comment for the card

classmethod _init_from_empty()

classmethod add_card(card, comment='')

Adds a PGAP card from BDF.add_card(...)

Parameters

cardBDFCard()

a BDFCard object

commentstr; default=’’

a comment for the card

cross_reference(model: BDF) → None

f0 = None

preload

ka = None

axial stiffness of closed gap

kb = None

axial stiffness of open gap

kt = None

transverse stiffness of closed gap

mu1 = None

static friction coeff

mu2 = None

kinetic friction coeff

pid = None

Property ID

pname_fid_map = {5: 'ka', 6: 'kb', 7: 'kt', 8: 'mu1', 9: 'mu2', 10: 'tmax', 11: 'mar', 12: 'trmin', 'KA': 'ka'}

raw_fields()

repr_fields()

Gets the fields in their simplified form

Returns

fieldsList[varies]

the fields that define the card

type = 'PGAP'

u0 = None

initial gap opening

uncross_reference() → None

Removes cross-reference links

write_card(size: int = 8, is_double: bool = False) → str

Writes the card with the specified width and precision

Parameters

sizeint (default=8)

size of the field; {8, 16}

is_doublebool (default=False)

is this card double precision

Returns

msgstr

the string representation of the card

class pyNastran.bdf.cards.properties.properties.PRAC2D(pid, mid, thick, iplane, nsm=0.0, gamma=0.5, phi=180.0, comment='')

Bases: pyNastran.bdf.cards.properties.properties.CrackProperty

CRAC2D Element Property Defines the properties and stress evaluation techniques to be used with the CRAC2D structural element.

dummy init

classmethod _init_from_empty()

classmethod add_card(card, comment='')

Adds a PRAC2D card from BDF.add_card(...)

Parameters

cardBDFCard()

a BDFCard object

commentstr; default=’’

a comment for the card

cross_reference(model: BDF) → None

Cross links the card so referenced cards can be extracted directly

Parameters

modelBDF()

the BDF object

gamma = None

Exponent used in the displacement field. See Remark 4. (Real; Default = 0.5)

iplane = None

Plane strain or plane stress option. Use 0 for plane strain; 1 for plane stress. (Integer = 0 or 1)

mid = None

Material ID

nsm = None

Non-structural mass per unit area.(Real >= 0.0; Default = 0)

phi = None

Angle (in degrees) relative to the element x-axis along which stress intensity factors are to be calculated. See Remark 4. (Real; Default = 180.0)

pid = None

Property ID

raw_fields()

repr_fields()

Gets the fields in their simplified form

Returns

fieldsList[varies]

the fields that define the card

type = 'PRAC2D'

uncross_reference() → None

Removes cross-reference links

validate()

card checking method that should be overwritten

class pyNastran.bdf.cards.properties.properties.PRAC3D(pid, mid, gamma=0.5, phi=180.0, comment='')

Bases: pyNastran.bdf.cards.properties.properties.CrackProperty

CRAC3D Element Property Defines the properties of the CRAC3D structural element.

dummy init

classmethod _init_from_empty()

classmethod add_card(card, comment='')

Adds a PRAC3D card from BDF.add_card(...)

Parameters

cardBDFCard()

a BDFCard object

commentstr; default=’’

a comment for the card

cross_reference(model: BDF) → None

Cross links the card so referenced cards can be extracted directly

Parameters

modelBDF()

the BDF object

gamma = None

Exponent used in the displacement field. See Remark 4. (Real; Default = 0.5)

mid = None

Material ID

phi = None

Angle (in degrees) relative to the element x-axis along which stress intensity factors are to be calculated. See Remark 4. (Real; Default = 180.0)

pid = None

Property ID

raw_fields()

repr_fields()

Gets the fields in their simplified form

Returns

fieldsList[varies]

the fields that define the card

type = 'PRAC3D'

uncross_reference() → None

Removes cross-reference links