zone.field.quantity

Syntax

s := zone.field.quantity

zone.field.quantity = s

Get/set the scalar quantity to retrieve when the value being obtained is a tensor. This value is ignored if the type is not a tensor. The available quantity names are listed in the following table.

Quantity Name	Description
intermediate	intermediate principal stress
maximum	the maximum (most positive) value of principal stress (note that compressive stresses are negative in FLAC)
mean	the mean pressure value defined as the trace of the tensor divided by 3. For stresses this is most often referred to as the pressure.
minimum	the minimum (most negative) principal stress (note that compressive stresses are negative in FLAC)
norm	The norm of the strain rate; see the equations below
octahedral	octahedral stress; see the equations below
shear-maximum	maximum shear stress
total-measure	distance of tensor value to the origin in principal space
volumetric	volumetric change or trace
von-mises	Von Mises measure; see the equations below
xx	\(xx\)-component of the tensor
xy	\(xy\)-component of the tensor
xz	\(xz\)-component of the tensor
yy	\(yy\)-component of the tensor
yz	\(yz\)-component of the tensor
zz	\(zz\)-component of the tensor

Returns:

s - the name of the scalar quantity to retrieve from the tensor

Accepts:

s - the name of the scalar quantity to retrieve from the tensor. Keyword matching rules are used. If no match is found, an error occurs.

Table 2: Equations for Zone Field Quantities

Quantity Name	Stress	Strain Increment	Strain Rate
norm	\(\sqrt{\sigma_{kk}}\)	\(\sqrt{{\epsilon^i}_{kk}}\)	\(\sqrt{{\epsilon^r}_{kk}}\)
octahedral	\(\sqrt{{2 \over 3} J_2}\)	\(\sqrt{{8 \over 3} J^i_2}\)	\(\sqrt{{8 \over 3} J^r_2}\)
von-mises	\(\sqrt{3J_2}\)	\(\sqrt{{4 \over 3} J^i_2}\)	\(\sqrt{{4 \over 3} J^r_2}\)
[ZC: please review equations above]