*VISCOSITY

Optional parameters

DEFINITION

Use this parameter to choose the shear viscosity of the material.

Set DEFINITION=BINGHAM PLASTIC to define the Bingham plastic viscous shear behavior. This behavior is valid only for fluid pipe and fluid pipe connector elements in Abaqus/Standard.

Set DEFINITION=CARREAU-YASUDA (Abaqus/Explicit only) to define the Carreau-Yasuda viscous shear behavior.

Set DEFINITION=CROSS (Abaqus/Explicit only) to define the Cross viscous shear behavior.

Set DEFINITION=ELLIS-METER (Abaqus/Explicit only) to define the Ellis-Meter viscous shear behavior.

Set DEFINITION=HERSCHEL-BULKLEY to define the Herschel-Bulkley viscous shear behavior. This behavior is valid for Abaqus/Explicit and is valid only for fluid pipe and fluid pipe connector elements in Abaqus/Standard.

Set DEFINITION=NEWTONIAN (default) to define Newtonian (linear) viscous shear behavior. This behavior is valid for Abaqus/Explicit and is valid only for fluid pipe and fluid pipe connector elements in Abaqus/Standard.

Set DEFINITION=POWELL-EYRING (Abaqus/Explicit only) to define the Powell-Eyring viscous shear behavior.

Set DEFINITION=POWER LAW to define the power law viscous shear behavior. This behavior is valid for Abaqus/Explicit and is valid only for fluid pipe and fluid pipe connector elements in Abaqus/Standard.

Set DEFINITION=TABULAR (Abaqus/Explicit only) to define the non-Newtonian viscous shear behavior in tabular form.

Set DEFINITION=USER (Abaqus/Explicit only) to define the viscous shear behavior in user subroutine VUVISCOSITY.

DEPENDENCIES

This parameter applies only to Abaqus/Explicit analyses.

Set this parameter equal to the number of field variable dependencies included in the definition of the viscosity, in addition to temperature. If this parameter is omitted, it is assumed that the viscosity depends only on temperature.

PROPERTIES

This parameter can be used only if DEFINITION=USER is specified.

Set this parameter equal to the number of property values needed as data in user subroutine VUVISCOSITY. The default value is 0.

Data lines to define the Bingham plastic viscous shear behavior (DEFINITION=BINGHAM PLASTIC)

First line

Shear viscosity at low shear rates, $η_{0}$ . (Units of FL⁻²T.)
Yield shear stress, $τ_{0}$ . (Units of FL⁻².)
Consistency index, $k$ . (Units of FL⁻²T.)
Temperature.
First field variable.
Second field variable.
Etc., up to four field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)

Fifth field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the coefficients of the Bingham plastic viscous shear model as a function of temperature and other predefined field variables.

Data lines to define the Carreau-Yasuda viscous shear behavior (DEFINITION=CARREAU-YASUDA)

First line

Shear viscosity at low shear rates (Newtonian limit), $η_{0}$ . (Units of FL⁻²T.)
Shear viscosity at large shear rates, $η_{\infty}$ . (Units of FL⁻²T.)
Time constant, $λ$ . (Units of T.)
Flow behavior index, $n$ .
$a$ .
Temperature.
First field variable.
Second field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than two)

Third field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the coefficients of the Carreau-Yasuda viscosity model as a function of temperature and other predefined field variables.

Data lines to define the Cross viscous shear behavior (DEFINITION=CROSS)

First line

Shear viscosity at low shear rates (Newtonian limit), $η_{0}$ . (Units of FL⁻²T.)
Shear viscosity at large shear rates, $η_{\infty}$ . (Units of FL⁻²T.)
Time constant, $λ$ . (Units of T.)
Flow behavior index, $n$ .
Temperature.
First field variable.
Second field variable.
Third field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)

Fourth field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the coefficients of the Cross viscosity model as a function of temperature and other predefined field variables.

Data lines to define the Ellis-Meter viscous shear behavior (DEFINITION=ELLIS-METER)

First line

Shear viscosity at low shear rates (Newtonian limit), $η_{0}$ . (Units of FL⁻²T.)
Shear viscosity at large shear rates, $η_{\infty}$ . (Units of FL⁻²T.)
Effective shear stress, $τ_{1 / 2}$ , at which the viscosity is 50% between the Newtonian limit, $η_{0}$ , and the infinite shear viscosity, $η_{\infty}$ . (Units of FL⁻².)
Flow behavior index, $n$ .
Temperature.
First field variable.
Second field variable.
Third field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)

Fourth field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the coefficients of the Ellis-Meter viscosity model as a function of temperature and other predefined field variables.

Data lines to define the Herschel-Bulkley viscous shear behavior (DEFINITION=HERSCHEL-BULKLEY)

First line

Shear viscosity at low shear rates, $η_{0}$ . (Units of FL⁻²T.)
Yield shear stress, $τ_{0}$ . (Units of FL⁻².)
Consistency index, $k$ . (Units of FL⁻²Tⁿ.)
Flow behavior index, $n$ .
Temperature.
First field variable.
Second field variable.
Third field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)

Fourth field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the coefficients of the Herschel-Bulkley viscosity model as a function of temperature and other predefined field variables.

Data lines to define Newtonian viscous shear behavior (DEFINITION=NEWTONIAN)

First line

Viscosity. (Units of FL⁻²T.)
Temperature.
First field variable.
Second field variable.
Etc., up to six field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than six)

Seventh field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the viscosity as a function of temperature and other predefined field variables.

Data lines to define the Powell-Eyring viscous shear behavior (DEFINITION=POWELL-EYRING)

First line

Shear viscosity at low shear rates (Newtonian limit), $η_{0}$ . (Units of FL⁻²T.)
Shear viscosity at large shear rates, $η_{\infty}$ . (Units of FL⁻²T.)
Time constant, $λ$ . (Units of T.)
Temperature.
First field variable.
Second field variable.
Etc., up to four field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)

Fifth field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the coefficients of the Powell-Eyring viscosity model as a function of temperature and other predefined field variables.

Data lines to define the power law viscous shear behavior (DEFINITION=POWER LAW)

First line

Consistency index, $k$ . (Units of FL⁻²Tⁿ.)
Flow behavior index, $n$ .
Maximum viscosity, $η_{m a x}$ . (Units of FL⁻²T.)
Minimum viscosity, $η_{m i n}$ . (Units of FL⁻²T.)
Temperature.
First field variable.
Second field variable.
Third field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)

Fourth field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the coefficients of the power law viscosity model as a function of temperature and other predefined field variables.

Data lines to define the viscous shear behavior in tabular form (DEFINITION=TABULAR)

First line

Viscosity, $η$ . (Units of FL⁻²T.)
Effective shear strain rate, $\dot{γ}$ . (Units of T⁻¹.)
Temperature.
First field variable.
Second field variable.
Etc., up to five field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than five)

Sixth field variable.
Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the viscosity as a function of effective shear strain rate, temperature, and other predefined field variables.

Data lines to define the material properties for the user-defined viscosity model (DEFINITION=USER)

No data lines are needed if the PROPERTIES parameter is omitted or set to 0. Otherwise, first line

Give the material properties, eight per line.

Repeat this data line as often as necessary to define the material properties.