Coordinate 1 is
,
coordinate 2 is .
At
the r-direction corresponds to the global
x-direction and the z-direction
corresponds to the global y-direction. This is important
when data must be given in global directions. Coordinate 1 must be greater than
or equal to zero.
Degree of freedom 1 is ,
degree of freedom 2 is .
Generalized axisymmetric elements with twist have an additional degree of
freedom, 5, corresponding to the twist angle
(in radians).
Abaqus
does not automatically apply any boundary conditions to nodes located along the
symmetry axis. You must apply radial or symmetry boundary conditions on these
nodes if desired.
In certain situations in
Abaqus/Standard it
may become necessary to apply radial boundary conditions on nodes that are
located on the symmetry axis to obtain convergence in nonlinear problems.
Therefore, the application of radial boundary conditions on nodes on the
symmetry axis is recommended for nonlinear problems.
Point loads
and moments, concentrated (nodal) fluxes, electrical currents, and seepage
should be given as the value integrated around the circumference (that is, the
total value on the ring).
Element Types
Stress/Displacement Elements without Twist
CAX3
3-node linear
CAX3H(S)
3-node linear, hybrid with constant pressure
CAX4(S)
4-node bilinear
CAX4H(S)
4-node bilinear, hybrid with constant pressure
CAX4I(S)
4-node bilinear, incompatible modes
CAX4IH(S)
4-node bilinear, incompatible modes, hybrid with linear pressure
CAX4R
4-node bilinear, reduced integration with hourglass control
CAX4RH(S)
4-node bilinear, reduced integration with hourglass control, hybrid with
constant pressure
CAX6(S)
6-node quadratic
CAX6H(S)
6-node quadratic, hybrid with linear pressure
CAX6M
6-node modified, with hourglass control
CAX6MH(S)
6-node modified, with hourglass control, hybrid with linear pressure
CAX8(S)
8-node biquadratic
CAX8H(S)
8-node biquadratic, hybrid with linear pressure
CAX8R(S)
8-node biquadratic, reduced integration
CAX8RH(S)
8-node biquadratic, reduced integration, hybrid with linear pressure
Active Degrees of Freedom
1, 2
Additional Solution Variables
The constant pressure hybrid elements have one additional variable and the
linear pressure elements have three additional variables relating to pressure.
Element types CAX4I and CAX4IH have five additional variables relating to the incompatible
modes.
Element types CAX6M and CAX6MH have two additional displacement variables.
Stress/Displacement Elements with Twist
CGAX3(S)
3-node linear
CGAX3H(S)
3-node linear, hybrid with constant pressure
CGAX4(S)
4-node bilinear
CGAX4H(S)
4-node bilinear, hybrid with constant pressure
CGAX4R(S)
4-node bilinear, reduced integration with hourglass control
CGAX4RH(S)
4-node bilinear, reduced integration with hourglass control, hybrid with
constant pressure
CGAX6(S)
6-node quadratic
CGAX6H(S)
6-node quadratic, hybrid with linear pressure
CGAX6M(S)
6-node modified, with hourglass control
CGAX6MH(S)
6-node modified, with hourglass control, hybrid with linear pressure
CGAX8(S)
8-node biquadratic
CGAX8H(S)
8-node biquadratic, hybrid with linear pressure
CGAX8R(S)
8-node biquadratic, reduced integration
CGAX8RH(S)
8-node biquadratic, reduced integration, hybrid with linear pressure
Active Degrees of Freedom
1, 2, 5
Additional Solution Variables
The constant pressure hybrid elements have one additional variable and the
linear pressure elements have three additional variables relating to pressure.
Element types CGAX6M and CGAX6MH have three additional displacement variables.
Diffusive Heat Transfer or Mass Diffusion Elements
DCAX3(S)
3-node linear
DCAX4(S)
4-node linear
DCAX6(S)
6-node quadratic
DCAX8(S)
8-node quadratic
Active Degrees of Freedom
11
Additional Solution Variables
None.
Forced Convection/Diffusion Elements
DCCAX2(S)
2-node
DCCAX2D(S)
2-node with dispersion control
DCCAX4(S)
4-node
DCCAX4D(S)
4-node with dispersion control
Active Degrees of Freedom
11
Additional Solution Variables
None.
Coupled Thermal-Electrical Elements
DCAX3E(S)
3-node linear
DCAX4E(S)
4-node linear
DCAX6E(S)
6-node quadratic
DCAX8E(S)
8-node quadratic
Active Degrees of Freedom
9, 11
Additional Solution Variables
None.
Coupled Temperature-Displacement Elements without Twist
CAX3T
3-node linear displacement and temperature
CAX4T(S)
4-node bilinear displacement and temperature
CAX4HT(S)
4-node bilinear displacement and temperature, hybrid with constant pressure
CAX4RT
4-node bilinear displacement and temperature, reduced integration with
hourglass control
CAX4RHT(S)
4-node bilinear displacement and temperature, reduced integration with
hourglass control, hybrid with constant pressure
CAX6MT
6-node modified displacement and temperature, with hourglass control
CAX6MHT(S)
6-node modified displacement and temperature, with hourglass control, hybrid
with linear pressure
CAX8T(S)
8-node biquadratic displacement, bilinear temperature
CAX8HT(S)
8-node biquadratic displacement, bilinear temperature, hybrid with linear
pressure
8-node biquadratic displacement, bilinear temperature, reduced integration,
hybrid with linear pressure
Active Degrees of Freedom
1, 2, 11 at corner nodes
1, 2 at midside nodes of second-order elements in
Abaqus/Standard
1, 2, 11 at midside nodes of the modified displacement and temperature
elements in
Abaqus/Standard
Additional Solution Variables
The constant pressure hybrid elements have one additional variable and the
linear pressure elements have three additional variables relating to pressure.
Element types CAX6MT and CAX6MHT have two additional displacement variables and one additional
temperature variable.
Coupled Temperature-Displacement Elements with Twist
CGAX3T(S)
3-node linear displacement and temperature
CGAX3HT(S)
3-node linear displacement and temperature, hybrid with constant pressure
CGAX4T(S)
4-node bilinear displacement and temperature
CGAX4HT(S)
4-node bilinear displacement and temperature, hybrid with constant pressure
CGAX4RT(S)
4-node bilinear displacement and temperature, reduced integration with
hourglass control
CGAX4RHT(S)
4-node bilinear displacement and temperature, reduced integration with
hourglass control, hybrid with constant pressure
CGAX6MT(S)
6-node modified displacement and temperature, with hourglass control
CGAX6MHT(S)
6-node modified displacement and temperature, with hourglass control, hybrid
with constant pressure
CGAX8T(S)
8-node biquadratic displacement, bilinear temperature
CGAX8HT(S)
8-node biquadratic displacement, bilinear temperature, hybrid with linear
pressure
8-node biquadratic displacement, bilinear temperature, reduced integration,
hybrid with linear pressure
Active Degrees of Freedom
1, 2, 5, 11 at corner nodes
1, 2, 5 at midside nodes of second-order elements
1, 2, 5, 11 at midside nodes of the modified displacement and temperature
elements
Additional Solution Variables
The constant pressure hybrid elements have one additional variable and the
linear pressure elements have three additional variables relating to pressure.
Element types CGAX6MT and CGAX6MHT have two additional displacement variables and one additional
temperature variable.
Pore Pressure Elements
CAX4P(S)
4-node bilinear displacement and pore pressure
CAX4PH(S)
4-node bilinear displacement and pore pressure, hybrid with constant
pressure
CAX4RP(S)
4-node bilinear displacement and pore pressure, reduced integration with
hourglass control
CAX4RPH(S)
4-node bilinear displacement and pore pressure, reduced integration with
hourglass control, hybrid with constant pressure
CAX6MP(S)
6-node modified displacement and pore pressure, with hourglass control
CAX6MPH(S)
6-node modified displacement and pore pressure, with hourglass control,
hybrid with linear pressure
8-node biquadratic displacement, bilinear pore pressure, reduced
integration, hybrid with linear pressure
Active Degrees of Freedom
1, 2, 8 at corner nodes
1, 2 at midside nodes
Additional Solution Variables
The constant pressure hybrid elements have one additional variable relating
to the effective pressure stress, and the linear pressure hybrid elements have
three additional variables relating to the effective pressure stress to permit
fully incompressible material modeling.
Element types CAX6MP and CAX6MPH have two additional displacement variables and one additional
pore pressure variable.
Coupled Temperature–Pore Pressure Elements
CAX4PT(S)
4-node bilinear displacement, pore pressure, and temperature
CAX4RPT(S)
4-node bilinear displacement, pore pressure, and temperature; reduced
integration with hourglass control
CAX4RPHT(S)
4-node bilinear displacement, pore pressure, and temperature; reduced
integration with hourglass control, hybrid with constant pressure
Active Degrees of Freedom
1, 2, 8, 11
Additional Solution Variables
The constant pressure hybrid elements have one additional variable relating
to the effective pressure stress to permit fully incompressible material
modeling.
Acoustic Elements
ACAX3
3-node linear
ACAX4R(E)
4-node linear, reduced integration with hourglass control
ACAX4(S)
4-node linear
ACAX6(S)
6-node quadratic
ACAX8(S)
8-node quadratic
Active Degrees of Freedom
8
Additional Solution Variables
None.
Piezoelectric Elements
CAX3E(S)
3-node linear
CAX4E(S)
4-node bilinear
CAX6E(S)
6-node quadratic
CAX8E(S)
8-node biquadratic
CAX8RE(S)
8-node biquadratic, reduced integration
Active Degrees of Freedom
1, 2, 9
Additional Solution Variables
None.
Nodal Coordinates Required
r, z at
Element Property Definition
For
element types DCCAX2 and DCCAX2D, you must specify the channel thickness of the element in the
(r–z) plane. The default is unit
thickness if no thickness is given.
For all other elements, you do
not need to specify the thickness.
Distributed
loads are available for all elements with displacement degrees of freedom. They
are specified as described in
Distributed Loads.
Distributed load magnitudes are per unit area or per unit volume. They do not
need to be multiplied by .
*dload
Load ID (*DLOAD): BR
FL−3
Body force in radial direction.
Load ID (*DLOAD): BZ
FL−3
Body force in axial direction.
Load ID (*DLOAD): BRNU
FL−3
Nonuniform body force in radial direction with magnitude supplied via user
subroutine
DLOAD in
Abaqus/Standard
and
VDLOAD in
Abaqus/Explicit.
Load ID (*DLOAD): BZNU
FL−3
Nonuniform body force in axial direction with magnitude supplied via user
subroutine
DLOAD in
Abaqus/Standard
and
VDLOAD in
Abaqus/Explicit.
Load ID (*DLOAD): CENT(S)
FL−4M−3T−2
Centrifugal load (magnitude input as ,
where
is the mass density per unit volume,
is the angular velocity). Not available for pore pressure elements.
Load ID (*DLOAD): CENTRIF(S)
T−2
Centrifugal load (magnitude is input as ,
where
is the angular velocity).
Load ID (*DLOAD): GRAV
LT−2
Gravity loading in a specified direction (magnitude is input as
acceleration).
Load ID (*DLOAD): HPn(S)
FL−2
Hydrostatic pressure on face n, linear in global
Y.
Load ID (*DLOAD): Pn
FL−2
Pressure on face n.
Load ID (*DLOAD): PnNU
FL−2
Nonuniform pressure on face n with magnitude
supplied via user subroutine
DLOAD in
Abaqus/Standard
and
VDLOAD in
Abaqus/Explicit.
Load ID (*DLOAD): SBF(E)
FL−5T2
Stagnation body force in radial and axial directions.
Load ID (*DLOAD): SPn(E)
FL−4T2
Stagnation pressure on face n.
Load ID (*DLOAD): TRSHRn
FL−2
Shear traction on face n.
Load ID (*DLOAD): TRSHRnNU(S)
FL−2
Nonuniform shear traction on face n with
magnitude and direction supplied via user subroutine
UTRACLOAD.
Load ID (*DLOAD): TRVECn
FL−2
General traction on face n.
Load ID (*DLOAD): TRVECnNU(S)
FL−2
Nonuniform general traction on face n with
magnitude and direction supplied via user subroutine
UTRACLOAD.
Load ID (*DLOAD): VBF(E)
FL−4T
Viscous body force in radial and axial directions.
Load ID (*DLOAD): VPn(E)
FL−3T
Viscous pressure on face n, applying a pressure
proportional to the velocity normal to the face and opposing the motion.
Foundations
Foundations are available for
Abaqus/Standard elements
with displacement degrees of freedom. They are specified as described in
Element Foundations.
*foundation
Load ID (*FOUNDATION): Fn(S)
FL−3
Elastic foundation on face n. For CGAX elements the elastic foundations are applied to degrees of
freedom
and
only.
Distributed Heat Fluxes
Distributed
heat fluxes are available for all elements with temperature degrees of freedom.
They are specified as described in
Thermal Loads.
Distributed heat flux magnitudes are per unit area or per unit volume. They do
not need to be multiplied by .
*dflux
Load ID (*DFLUX): BF
JL−3T−1
Heat body flux per unit volume.
Load ID (*DFLUX): BFNU
JL−3T−1
Nonuniform heat body flux per unit volume with magnitude supplied via user
subroutine
DFLUX in
Abaqus/Standard
and
VDFLUX in
Abaqus/Explicit.
Load ID (*DFLUX): Sn
JL−2T−1
Heat surface flux per unit area into face n.
Load ID (*DFLUX): SnNU
JL−2T−1
Nonuniform heat surface flux per unit area into face
n with magnitude supplied via user subroutine
DFLUX in
Abaqus/Standard
and
VDFLUX in
Abaqus/Explicit.
Film Conditions
Film conditions
are available for all elements with temperature degrees of freedom. They are
specified as described in
Thermal Loads.
*film
Load ID (*FILM): Fn
JL−2T−1−1
Film coefficient and sink temperature (units of )
provided on face n.
Load ID (*FILM): FnNU(S)
JL−2T−1−1
Nonuniform film coefficient and sink temperature (units of
)
provided on face n with magnitude supplied via user
subroutine
FILM.
Radiation Types
Radiation conditions are available for all elements with temperature
degrees of freedom. They are specified as described in
Thermal Loads.
*radiate
Load ID (*RADIATE): Rn
Dimensionless
Emissivity and sink temperature provided for face
n.
Distributed Flows
Distributed
flows are available for all elements with pore pressure degrees of freedom.
They are specified as described in
Pore Fluid Flow.
Distributed flow magnitudes are per unit area or per unit volume. They do not
need to be multiplied by .
*flow
Load ID (*FLOW): Qn(S)
F−1L3T−1
Seepage coefficient and reference sink pore pressure (units of
FL−2) provided on face n.
Load ID (*FLOW): QnD(S)
F−1L3T−1
Drainage-only seepage coefficient provided on face
n.
Load ID (*FLOW): QnNU(S)
F−1L3T−1
Nonuniform seepage coefficient and reference sink pore pressure (units of
FL−2) provided on face n
with magnitude supplied via user subroutine
FLOW.
*dflow
Load ID (*DFLOW): Sn(S)
LT−1
Prescribed pore fluid effective velocity (outward from the face) on face
n.
Load ID (*DFLOW): SnNU(S)
LT−1
Nonuniform prescribed pore fluid effective velocity (outward from the face)
on face n with magnitude supplied via user
subroutine
DFLOW.
Distributed Impedances
Distributed impedances are available for all elements with acoustic
pressure degrees of freedom. They are specified as described in
Acoustic and Shock Loads.
*impedance
Load ID (*IMPEDANCE): In
None
Name of the impedance property that defines the impedance on face
n.
Electric Fluxes
Electric fluxes are available for piezoelectric elements. They are
specified as described in
Piezoelectric Analysis.
*decharge
Load ID (*DECHARGE): EBF(S)
CL−3
Body flux per unit volume.
Load ID (*DECHARGE): ESn(S)
CL−2
Prescribed surface charge on face n.
Distributed Electric Current Densities
Distributed electric current densities are available for coupled
thermal-electrical elements. They are specified as described in
Coupled Thermal-Electrical Analysis.
*decurrent
Load ID (*DECURRENT): CBF(S)
CL−3T−1
Volumetric current source density.
Load ID (*DECURRENT): CSn(S)
CL−2T−1
Current density on face n.
Distributed Concentration Fluxes
Distributed concentration fluxes are available for mass diffusion
elements. They are specified as described in
Mass Diffusion Analysis.
*dflux
Load ID (*DFLUX): BF(S)
PT−1
Concentration body flux per unit volume.
Load ID (*DFLUX): BFNU(S)
PT−1
Nonuniform concentration body flux per unit volume with magnitude supplied
via user subroutine
DFLUX.
Load ID (*DFLUX): Sn(S)
PLT−1
Concentration surface flux per unit area into face
n.
Load ID (*DFLUX): SnNU(S)
PLT−1
Nonuniform concentration surface flux per unit area into face
n with magnitude supplied via user subroutine
DFLUX.
Surface-Based Loading
Distributed Loads
Surface-based
distributed loads are available for all elements with displacement degrees of
freedom. They are specified as described in
Distributed Loads.
Distributed load magnitudes are per unit area or per unit volume. They do not
need to be multiplied by .
*dsload
Load ID (*DSLOAD): HP(S)
FL−2
Hydrostatic pressure on the element surface, linear in global
Y.
Load ID (*DSLOAD): P
FL−2
Pressure on the element surface.
Load ID (*DSLOAD): PNU
FL−2
Nonuniform pressure on the element surface with magnitude supplied via user
subroutine
DLOAD in
Abaqus/Standard
and
VDLOAD in
Abaqus/Explicit.
Load ID (*DSLOAD): SP(E)
FL−4T2
Stagnation pressure on the element surface.
Load ID (*DSLOAD): TRSHR
FL−2
Shear traction on the element surface.
Load ID (*DSLOAD): TRSHRNU(S)
FL−2
Nonuniform shear traction on the element surface with magnitude and
direction supplied via user subroutine
UTRACLOAD.
Load ID (*DSLOAD): TRVEC
FL−2
General traction on the element surface.
Load ID (*DSLOAD): TRVECNU(S)
FL−2
Nonuniform general traction on the element surface with magnitude and
direction supplied via user subroutine
UTRACLOAD.
Load ID (*DSLOAD): VP(E)
FL−3T
Viscous pressure applied on the element surface. The viscous pressure is
proportional to the velocity normal to the face and opposing the motion.
Distributed Heat Fluxes
Surface-based heat fluxes are available for all elements with temperature
degrees of freedom. They are specified as described in
Thermal Loads.
Distributed heat flux magnitudes are per unit area or per unit volume. They do
not need to be multiplied by .
*dsflux
Load ID (*DSFLUX): S
JL−2T−1
Heat surface flux per unit area into the element surface.
Load ID (*DSFLUX): SNU
JL−2T−1
Nonuniform heat surface flux per unit area into the element surface with
magnitude supplied via user subroutine
DFLUX in
Abaqus/Standard
and
VDFLUX in
Abaqus/Explicit.
Film Conditions
Surface-based
film conditions are available for all elements with temperature degrees of
freedom. They are specified as described in
Thermal Loads.
*sfilm
Load ID (*SFILM): F
JL−2T−1−1
Film coefficient and sink temperature (units of )
provided on the element surface.
Load ID (*SFILM): FNU(S)
JL−2T−1−1
Nonuniform film coefficient and sink temperature (units of
)
provided on the element surface with magnitude supplied via user subroutine
FILM.
Radiation Types
Surface-based radiation conditions are available for all elements with
temperature degrees of freedom. They are specified as described in
Thermal Loads.
*sradiate
Load ID (*SRADIATE): R
Dimensionless
Emissivity and sink temperature provided for the element surface.
Distributed Flows
Surface-based
distributed flows are available for all elements with pore pressure degrees of
freedom. They are specified as described in
Pore Fluid Flow.
Distributed flow magnitudes are per unit area or per unit volume. They do not
need to be multiplied by .
*sflow
Load ID (*SFLOW): Q(S)
F−1L3T−1
Seepage coefficient and reference sink pore pressure (units of
FL−2) provided on the element surface.
Load ID (*SFLOW): QD(S)
F−1L3T−1
Drainage-only seepage coefficient provided on the element surface.
Load ID (*SFLOW): QNU(S)
F−1L3T−1
Nonuniform seepage coefficient and reference sink pore pressure (units of
FL−2) provided on the element surface with magnitude
supplied via user subroutine
FLOW.
*dsflow
Load ID (*DSFLOW): S(S)
LT−1
Prescribed pore fluid effective velocity outward from the element surface.
Load ID (*DSFLOW): SNU(S)
LT−1
Nonuniform prescribed pore fluid effective velocity outward from the element
surface with magnitude supplied via user subroutine
DFLOW.
Distributed Impedances
Surface-based impedances are available for all elements with acoustic
pressure degrees of freedom. They are specified as described in
Acoustic and Shock Loads.
Incident Wave Loading
Surface-based incident wave loads are available for all elements with
displacement degrees of freedom or acoustic pressure degrees of freedom. They
are specified as described in
Acoustic and Shock Loads.
If the incident wave field includes a reflection off a plane outside the
boundaries of the mesh, this effect can be
included.
Electric Fluxes
Surface-based electric fluxes are available for piezoelectric elements.
They are specified as described in
Piezoelectric Analysis.
*dsecharge
Load ID (*DSECHARGE): ES(S)
CL−2
Prescribed surface charge on the element surface.
Distributed Electric Current Densities
Surface-based electric current densities are available for coupled
thermal-electrical elements. They are specified as described in
Coupled Thermal-Electrical Analysis.
*dsecurrent
Load ID (*DSECURRENT): CS(S)
CL−2T−1
Current density on the element surface.
Element Output
Output is in global directions unless a local coordinate system is
assigned to the element through the section definition (Orientations)
in which case output is in the local coordinate system (which rotates with the
motion in large-displacement analysis). See
State storage
for details. For regular axisymmetric elements, the local orientation must be
in the –z
plane with
being a principal direction. For generalized axisymmetric elements with twist,
the local orientation can be
arbitrary.
Stress, Strain, and Other Tensor Components
Stress and other tensors (including strain tensors) are available for
elements with displacement degrees of freedom. All tensors have the same
components. For example, the stress components are as follows:
For
elements with displacement degrees of freedom without twist:
S11
Stress in the radial direction or in the local 1-direction.
S22
Stress in the axial direction or in the local 2-direction.
S33
Hoop direct stress.
S12
Shear stress.
For elements with
displacement degrees of freedom with twist:
S11
Stress in the radial direction or in the local 1-direction.
S22
Stress in the axial direction or in the local 2-direction.
S33
Stress in the circumferential direction or in the local 3-direction.
S12
Shear stress.
S13
Shear stress.
S23
Shear stress.
Heat Flux Components
Available for elements with temperature degrees of freedom.
HFL1
Heat flux in the radial direction or in the local 1-direction.
HFL2
Heat flux in the axial direction or in the local 2-direction.
Pore Fluid Velocity Components
Available for elements with pore pressure degrees of freedom, except for
acoustic elements.
FLVEL1
Pore fluid effective velocity in the radial direction or in the local
1-direction.
FLVEL2
Pore fluid effective velocity in the axial direction or in the local
2-direction.
Mass Concentration Flux Components
Available for elements with normalized concentration degrees of
freedom.
MFL1
Concentration flux in the radial direction or in the local 1-direction.
MFL2
Concentration flux in the axial direction or in the local 2-direction.
Electrical Potential Gradient
Available for elements with electrical potential degrees of
freedom.
EPG1
Electrical potential gradient in the 1-direction.
EPG2
Electrical potential gradient in the 2-direction.
Electrical Flux Components
Available for piezoelectric elements.
EFLX1
Electrical flux in the 1-direction.
EFLX2
Electrical flux in the 2-direction.
Electrical Current Density Components
Available for coupled thermal-electrical elements.