forces_moments Module

defines methods to access force/moment/pressure/temperature data:

• get_forces_moments_array(model, p0, load_case_id,

  eid_map, nnodes, normals, dependents_nodes, nid_map=None, include_grav=False)

• get_pressure_array(model, load_case, eids, stop_on_failure=True)

• get_temperatures_array(model, load_case_id, nid_map=None,

  fdtype=’float32’)

• get_load_arrays(model, subcase_id, nid_map, eid_map, node_ids, normals)

pyNastran.bdf.mesh_utils.forces_moments.get_forces_moments_array(model: BDF, p0: np.ndarray, load_case_id: int, eid_map: dict[int, int], nnodes: int, normals: np.ndarray, dependents_nodes, nid_map: dict[int, int] | None = None, include_grav: bool = False, fdtype: str = 'float32') → tuple[bool, tuple[np.ndarray, np.ndarray, np.ndarray, np.ndarray]]

Gets the forces/moments on the nodes.

Parameters:

p0(3, ) float ndarray

the reference location

load_case_idint

the load id

nid_mapdict[int nidint index]

mapping of node id to node index (e.g., forces)

eid_mapdict[int eidint index]

mapping of element id to array index (e.g., normals)

nnodesint

the number of nodes in nid_map

normals(nelements, 3) float ndarray

the normal vectors for the shells what about solids???

dependents_nodes???

???

include_gravbool; default=False

is the mass of the elements considered; unused

Returns:

is_loads: bool

are there any loads?

temperature_datatuple(temperature_key, temperatures)

temperature_keystr

One of the following:

TEMPERATURE(MATERIAL) TEMPERATURE(INITIAL) TEMPERATURE(LOAD) TEMPERATURE(BOTH)

temperatures(nnodes, 1) float ndarray

the temperatures

load_datatuple(centroidal_pressures, forces, moments, spcd)

centroidal_pressures(nelements, 1) float ndarray

the pressure

forces/moments(nnodes, 3) float ndarray

the forces/moments

spcd(nnodes, 3) float ndarray

the SPCD load application

Considers

FORCE

PLOAD2 - CTRIA3, CQUAD4, CSHEAR

PLOAD4 - CTRIA3, CTRIA6, CTRIAR

CQUAD4, CQUAD8, CQUAD, CQUADR, CSHEAR CTETRA, CPENTA, CHEXA

SPCD

pyNastran.bdf.mesh_utils.forces_moments.get_load_arrays(model: BDF, subcase_id: int, eid_map, node_ids, normals, nid_map=None, stop_on_failure: bool = True, fdtype: str = 'float32') → tuple[np.ndarray, np.ndarray, np.ndarray, np.ndarray]

Gets the following load arrays

Loads include:

• Temperature

• Pressure (Centroidal)

• Forces

• SPCD

Parameters:

modelBDF()

the BDF object

subcase_idint

the subcase id

eid_mapdict[int eidint index]

???

node_idslist[int] / int ndarray

the node ids in sorted order

normals(nelements, 3) ndarray?

the normal vectors for the shells what about solids???

Returns:

found_loadbool

a flag that indicates if load data was found

found_temperaturebool

a flag that indicates if temperature data was found

temperature_datatuple(temperature_key, temperatures)

temperature_keystr

One of the following:

TEMPERATURE(MATERIAL) TEMPERATURE(INITIAL) TEMPERATURE(LOAD) TEMPERATURE(BOTH)

temperatures(nnodes, 1) float ndarray

the temperatures

load_datatuple(centroidal_pressures, forces, moments, spcd)

centroidal_pressures(nelements, 1) float ndarray

the pressure

forces/moments(nnodes, 3) float ndarray

the forces/moments

spcd(nnodes, 3) float ndarray

the SPCD load application

pyNastran.bdf.mesh_utils.forces_moments.get_pressure_array(model: BDF, load_case_id: int, eids, stop_on_failure: bool = True, fdtype: str = 'float32') → tuple[bool, np.ndarray]

Gets the shell pressures for a load case.

Parameters:

load_case_idint

the load case to get the pressure contour for

eids(nelements, ) int ndarray

the element ids in sorted order

stop_on_failurebool; default=True

crashes if the load_case_id doesn’t exist

Returns:

is_pressurebool

is there pressure data

pressures(nelements, 1) float ndarray

ndarray : the centroidal pressures

pyNastran.bdf.mesh_utils.forces_moments.get_temperatures_array(model: BDF, load_case_id: int, nid_map: dict[int, int] | None = None, fdtype: str = 'float32') → tuple[bool, np.ndarray]

Builds the temperature array based on thermal cards.

Parameters:

load_case_idint

the load id

nid_mapdict[node_id, value] default=None -> auto

node_idint

node id

valueint

index

dtypestr; default=’float32’

the type of the temperature array

Returns:

is_temperaturesbool

is there temperature data

temperatures(nnodes, ) float ndarray

the temperatures