ball.stress

Syntax

t = ball.stress(bp)

Get the stress tensor arising from all contacts acting on the ball. The stress tensor is computed as:

\[\sigma^{(\phi)}_{ij} = \frac{1}{V} \sum_{n_c}(x^{(c)}_i - x^{(\phi)}_i) F^{(c,\phi)}_j\]

Returns:

t - stress tensor

Arguments:

bp - ball pointer

Stresses are expressed in the global system. Note that compressive stresses are negative.

Component Access

f = ball.stress (bp)->xx

f = ball.stress.xx(bp)

Get the \(xx\)-value of the stress.

Returns:

f - \(xx\)-value of the stress tensor

Arguments:

bp - ball pointer

Access other tensor components (\(yy\), \(zz\), \(xy\), \(xz\), \(yz\)) by substituting the component name where \(xx\) appears above. \(xz\), \(yz\), and \(zz\) are 3D only. See Member Access Operator for information about accessing members from data types using ->.

Deprecated Component Access

Component access by adding optional integer(s) in the function arguments (e.g., f = ball. stress(bp, 1, 1)) is deprecated. It remains available but will not be supported in future versions. See Component Access with Integers in FISH on the Deprecated Commands and FISH page for details.

This is hidden. Added to include remaining vector component access functions for inline help.

f = ball.stress.yy(bp)

f = ball.stress.zz(bp) (3D only)

f = ball.stress.xy(bp)

f = ball.stress.xz(bp) (3D only)

f = ball.stress.yz(bp) (3D only)